Connection node device, optical transmission system, and connection method

Abstract

The output port switching section is connected to the first optical transmission path, the second optical transmission path, and a connection information processing section that acquires connection information including information about the optical transmission path, i.e., transmission path information. In an initial state, the output port switching section sets the connection destination of the first optical transmission path to the connection information processing section. The control section sends transmission mode information to an optical transmission / reception section of the optical communication device connected to the first optical transmission path via the first optical transmission path. The transmission mode information indicates a transmission mode determined based on the connection information of the first optical transmission path acquired from an optical signal transmitted from the optical transmission / reception section to the connection information processing section, connection request data transmitted from the optical transmission / reception section in the form of an optical signal, and the transmission path information of the second optical transmission path. After the control section sends the transmission mode information, the output port switching section performs switching processing that switches the connection destination of the first optical transmission path from the connection information processing section to the second optical transmission path.

Description

Technical Field

[0001] This invention relates to a server connection device, an optical transmission system, and a connection method. Background Technology

[0002] With the increasing functionality of digital signal processing (DSP) for optical transmission, not only modulation methods but also various parameters related to transmission performance, such as baud rate, type of error correction code (FEC), and number of carriers, have become more diverse. To address this, a technique for selecting the optimal transmission mode from a combination of multiple transmission performance-related parameters and a message transmission method for selecting the optimal transmission mode have been proposed.

[0003] For example, Patent Document 1 discloses a method for selecting the optimal modulation scheme based on training signals. Patent Document 2 discloses a method for message transmission that selects the optimal transmission mode corresponding to various parameters related to transmission performance, such as the same baud rate, error correction code type, and number of carriers, other than the modulation scheme.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 5753604

[0007] Patent Document 2: International Publication No. 2020 / 031514 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] However, in the technologies described in Patent Documents 1 and 2, when setting the light path through multiple optical transmission paths such as dark fiber and carrier networks, it is impossible to select the optimal transmission mode to set the light path. In other words, when setting the light path through multiple optical transmission paths such as dark fiber and carrier networks, it is necessary to manually measure the characteristics of the dark fiber from the user terminal device in the data center to the edge terminal device of the carrier network. Therefore, there are cost and time issues in setting the light path between users. In addition, some of the resources available in the carrier network are used for other communications, so there is a limitation on the resources that can be used when setting the light path, and this limitation of resources also needs to be considered in setting the light path between users.

[0010] In view of the above, the object of the present invention is to provide a technology that enables connection of optical transmitting and receiving units of an optical communication device through multiple optical transmission paths without manual operation, by using the optical path of the optimal transmission mode.

[0011] Solution for solving the problem

[0012] One aspect of the present invention is a connection node device comprising: a connection information processing unit that acquires connection information including transmission path information, the transmission path information being information related to an optical transmission path; an output port switching unit connected to a first optical transmission path, a second optical transmission path, and the connection information processing unit, wherein in an initial state, the connection destination of the first optical transmission path is set to the connection information processing unit; and a control unit that transmits transmission mode information through the first optical transmission path to an optical transmission and reception unit of an optical communication device connected to the first optical transmission path, the transmission mode information representing a transmission mode determined based on the connection information of the first optical transmission path acquired by the connection information processing unit from an optical signal transmitted by the optical transmission and reception unit, connection request data transmitted by the optical transmission and reception unit in a manner included in the optical signal, and transmission path information of the second optical transmission path, wherein the output port switching unit performs a switching process to switch the connection destination of the first optical transmission path from the connection information processing unit to the second optical transmission path after the control unit transmits the transmission mode information.

[0013] One aspect of the present invention is an optical transmission system comprising: the aforementioned connection node device; a first optical communication device connected to the other end of a first optical transmission path to which one end is connected; and a second optical communication device directly or indirectly connected to the connection node device via a second optical transmission path to which one end is connected. In the optical transmission system, the first optical communication device includes an optical transmitting / receiving unit that receives transmission mode information transmitted by the control unit of the connection node device via the first optical transmission path, and transmits and receives optical signals via the first optical transmission path in accordance with the transmission mode indicated by the received transmission mode information. The second optical communication device includes an optical transmitting / receiving unit that receives the transmission mode information and transmits and receives optical signals via the second optical transmission path in accordance with the transmission mode indicated by the received transmission mode information. After the control unit transmits the transmission mode information to the first optical communication device via the first optical transmission path, the output port switching unit of the connection node device connects the optical transmitting / receiving unit of the first optical communication device and the optical transmitting / receiving unit of the second optical communication device via the first optical transmission path and the second optical transmission path through a switching process.

[0014] One aspect of the present invention is a connection method in which an output port switching unit is connected to a first optical transmission path, a second optical transmission path, and a connection information processing unit. In an initial state, the connection destination of the first optical transmission path is set to the connection information processing unit. The connection information processing unit acquires connection information including transmission path information as information related to the optical transmission path. A control unit sends transmission mode information through the first optical transmission path to an optical transmission and reception unit of an optical communication device connected to the first optical transmission path. The transmission mode information represents a transmission mode determined based on the connection information of the first optical transmission path acquired by the connection information processing unit from the optical signal transmitted by the optical transmission and reception unit, the connection request data transmitted by the optical transmission and reception unit in a manner included in the optical signal, and the transmission path information of the second optical transmission path. After the control unit sends the transmission mode information, the output port switching unit performs a switching process to switch the connection destination of the first optical transmission path from the connection information processing unit to the second optical transmission path.

[0015] The effects of the invention

[0016] According to the present invention, when connecting the optical transmitting and receiving units of an optical communication device via multiple optical transmission paths, the connection can be made without manual operation by using the optical path of the optimal transmission mode. Attached Figure Description

[0017] Figure 1 This is a block diagram illustrating the structure of the optical transmission system in the first embodiment.

[0018] Figure 2 This is one of the diagrams showing the internal structure of the connection node device and the optical communication device in the first embodiment, as well as the connection relationship of the optical transmission paths of the connection node device and the optical communication device respectively.

[0019] Figure 3 This is a diagram illustrating the processing flow of the optical transmission system in the first embodiment.

[0020] Figure 4 This is a diagram (Part Two) showing the internal structure of the connection node device and the optical communication device in the first embodiment, as well as the connection relationship of the optical transmission paths of the connection node device and the optical communication device respectively.

[0021] Figure 5 This is a block diagram illustrating the structure of the optical transmission system in the second embodiment.

[0022] Figure 6 This is a diagram illustrating the processing flow of the optical transmission system in the second embodiment.

[0023] Figure 7 This is a diagram illustrating one of the other structural examples of the optical transmission system in the second embodiment.

[0024] Figure 8 This is a block diagram illustrating the structure of the optical transmission system in the third embodiment.

[0025] Figure 9 This is one of the diagrams showing the internal structure of the connection node device and the optical communication device in the third embodiment, as well as the connection relationship of the optical transmission paths of the connection node device and the optical communication device respectively.

[0026] Figure 10 This is a diagram illustrating the processing flow of the optical transmission system in the third embodiment.

[0027] Figure 11 This is a diagram (Part Two) showing the internal structure of the connection node device and the optical communication device in the third embodiment, as well as the connection relationship of the optical transmission paths of the connection node device and the optical communication device respectively.

[0028] Figure 12 This is a diagram (Part 3) showing the internal structure of the connection node device and the optical communication device in the third embodiment, as well as the connection relationship of the optical transmission paths of the connection node device and the optical communication device respectively.

[0029] Figure 13 This is a diagram illustrating one of the other structural examples of the optical transmission system in the third embodiment.

[0030] Figure 14 This is a diagram illustrating another structural example (two) of the optical transmission system in the second embodiment.

[0031] Figure 15 This is a diagram illustrating another structural example (two) of the optical transmission system in the third embodiment.

[0032] Figure 16 This is a diagram illustrating another structural example (third example) of the optical transmission system in the second embodiment.

[0033] Figure 17 This is a block diagram illustrating the structure of the optical transmission system in the fourth embodiment.

[0034] Figure 18 This is a diagram showing the data structure of the connection status table of the transmission path design unit in the fourth embodiment.

[0035] Figure 19 This is a diagram illustrating the processing flow of the optical transmission system in the fourth embodiment.

[0036] Figure 20This is a diagram illustrating the flow of the transmission mode determination process in the fourth embodiment. Detailed Implementation

[0037] (First Implementation)

[0038] The embodiments of the present invention will now be described with reference to the accompanying drawings. Figure 1 This is a block diagram illustrating the structure of the optical transmission system 100 according to the first embodiment. The optical transmission system 100 includes a connection node device 1, an optical communication device 2X, an optical communication device 2Y, an optical transmission path 51, an optical transmission path 52, and a connection line 3. The optical transmission path 51 connects the optical communication device 2X to the connection node device 1. The optical transmission path 52 connects the optical communication device 2Y to the connection node device 1. The connection line 3 connects the connection node device 1 to the optical communication device 2Y. The optical communication device 2X is, for example, a communication device used by a user. The optical communication device 2Y is, for example, an optical transmission device owned by a telecommunications operator, i.e., a node device in a communication network, or a white-box switch owned by a telecommunications operator or data center operator.

[0039] Not only referencing Figure 1 Moreover, referencing Figure 2 The internal structures of the connecting node device 1, optical communication device 2X, and optical communication device 2Y will be explained below. Furthermore, in... Figure 1 and Figure 2 In the connecting lines shown, the thin arrow solid lines indicate the path of electrical data signals, the thick arrow solid lines indicate the path of optical data signals, the thin arrow dashed lines indicate the path of electrical control signals, the thin solid lines indicate electrical connections, the thick solid lines indicate connections using optical lines, and the dotted lines indicate connecting lines. The same applies to other figures unless otherwise defined.

[0040] Figure 1 The optical transmission path 51 shown is as follows Figure 2 The optical transmission path 51 includes optical fibers such as dark fiber 51T and 51R. Furthermore, to distinguish the two optical fibers in the optical transmission path 51, the reference numeral "51" is labeled with the letters "T" and "R" for clarity. The reference numeral "T" indicates the transmission direction as observed from the optical communication device 2X, and the reception direction as observed from the connection node device 1 and the optical communication device 2Y. The reference numeral "R" indicates the reception direction as observed from the optical communication device 2X, and the transmission direction as observed from the connection node device 1 and the optical communication device 2Y. Figure 1 The optical transmission path 52 shown is as follows Figure 2As shown, it includes optical fibers 52T and 52R, which constitute a carrier network for a telecommunications operator. Connection line 3 is a communication line, which can be a wired communication line such as a dedicated line, a wireless communication line, a mobile communication network, the Internet, or a DCN (Data Communication Network). Alternatively, in the case of a connection using an optical communication line, a portion of the overhead area of ​​a digital frame transmitted via optical signals can be allocated to connection line 3.

[0041] Optical communication devices, such as 2X, are switches that transmit data provided by external devices and output received data back to those external devices. Figure 2 As shown, the optical communication device 2X includes a control unit 20X and an optical transceiver unit 21X. The control unit 20X is connected to the optical transceiver unit 21X and performs control over the optical transceiver unit 21X, as well as input and output of information between the two units. For example, when initiating a connection to the optical transceiver unit 21X of the optical communication device 2Y, the control unit 20X generates a connection request indication signal.

[0042] The optical transceiver unit 21X includes an IF (Interface) unit 22X, an optical transceiver unit 24X, an optical receiver unit 27X, a digital signal processing unit 23X, and a control unit 71X. The IF unit 22X connects the optical fiber 51T of the optical transmission path 51 to the optical transceiver unit 24X. The IF unit 22X also connects the optical fiber 51R of the optical transmission path 51 to the optical receiver unit 27X.

[0043] When the control unit 71X receives a connection request indication signal from the control unit 20X, it generates data representing the connection request (hereinafter referred to as "connection request data"). Here, the connection request data refers to data containing information such as the connection destination address, the connection source address, the desired bit rate, and the specifications of the optical transmitter / receiver unit 21X. The specifications of the optical transmitter / receiver unit 21X include, for example, the modulation method usable in the optical transmitter unit 24X, the FEC type usable in the digital signal processing unit 23X, the baud rate, and the type of light source possessed by the optical transmitter unit 24X.

[0044] Here, information indicating the type of light source refers to information such as whether the light source is a type that outputs a predetermined single wavelength or a type that outputs a different wavelength, as well as information that includes not only this information but also information about the wavelength or wavelength range that the light source can output. In the case of the optical communication device 2X, the optical transmitter 24X includes a single-wavelength light source 25X. Therefore, the specifications of the optical transmitter / receiver 21X will include information about whether the light source included in the optical transmitter 24X outputs a predetermined single wavelength and information indicating the wavelength that the light source can output.

[0045] Address information for identifying each optical transmitter / receiver unit is pre-attached to the optical transmitter / receiver unit 21X of optical communication device 2X and the optical transmitter / receiver unit 21Y of optical communication device 2Y. Control unit 20X pre-stores the desired bit rate and the address information of the connection destination in its internal storage area. Control unit 71X pre-stores the address information attached to the optical transmitter / receiver unit 21X equipped with control unit 71X in its internal storage area. For example, when the optical transmitter / receiver unit 21X is configured to be connected to optical communication device 2X, control unit 71X obtains the specification information of optical transmitter / receiver unit 21X from optical transmitter unit 24X and digital signal processing unit 23X and stores it in its internal storage area. However, control unit 20X does not pre-store the address information of the connection destination in its internal storage area; for example, it may be configured to obtain and retrieve the address information of the connection destination specified by the user of optical communication device 2X, or it may be configured to obtain the address information of the connection destination from connection node device 1. In addition, the control unit 20X does not pre-store the desired bit rate in its internal storage area. Instead, it can be configured to accept user input to obtain and acquire data of the bit rate specified by the user in advance as the desired bit rate.

[0046] For example, when requesting a connection to the optical transceiver unit 21Y of the optical communication device 2Y, the control unit 20X generates a connection request indication signal containing the address information of the optical transceiver unit 21Y and the desired bit rate, and outputs it to the control unit 71X. The control unit 71X reads the address information of the optical transceiver unit 21Y contained in the connection request indication signal received from the control unit 20X and determines it as the connection destination address information, and reads the address information of the optical transceiver unit 21X stored in its internal storage area and determines it as the connection party address information. The control unit 71X generates connection request data containing the connection destination address information and connection party address information determined as described above, the desired bit rate contained in the connection request indication signal, and the specification information of the optical transceiver unit 21X stored in its internal storage area. The control unit 71X outputs the generated connection request data to the digital signal processing unit 23X.

[0047] The digital signal processing unit 23X, for example, is a DSP, and is connected to the control unit 71X, the optical transmitter 24X, and the optical receiver 27X. The digital signal processing unit 23X acquires transmission data, such as client signals, provided by an external device connected to the optical communication device 2X. Additionally, the digital signal processing unit 23X acquires connection request data generated by the control unit 71X.

[0048] The digital signal processing unit 23X generates a transmission data signal in the form of a transmission frame that includes the acquired transmission data in the payload. Alternatively, the digital signal processing unit 23X can generate a transmission data signal in a manner that includes the acquired connection request data in the idle area of ​​the transmission frame overhead. Furthermore, it is also possible that the digital signal processing unit 23X does not transmit transmission data during the timing prior to determining the transmission mode information, thus generating a transmission data signal without including the transmission data in the payload. The digital signal processing unit 23X outputs the generated transmission data signal to the optical transmission unit 24X.

[0049] The digital signal processing unit 23X acquires the received data signal from the electrical signal output by the optical receiver 27X. The digital signal processing unit 23X reads the data contained in the payload or overhead of the acquired received data signal. The digital signal processing unit 23X outputs the client signal from the read data to an external device. Additionally, the digital signal processing unit 23X outputs connection request data and control information contained in the overhead from the read data to the control unit 71X. The control unit 71X outputs control signals to the single-wavelength light source 25X and the optical modulator 26X, as indicated by the dashed arrow.

[0050] The optical transmitter 24X includes a single-wavelength light source 25X and an optical modulator 26X. The single-wavelength light source 25X generates and outputs continuous light of a predetermined single wavelength at a power specified by a control signal (hereinafter referred to as the "output optical power specification signal") output by the control unit 71X, representing the output optical power. The optical modulator 26X modulates the continuous light output by the single-wavelength light source 25X according to the modulation mode specified by a control signal (hereinafter referred to as the "modulation mode specification signal") output by the control unit 71X, based on the transmission data signal output by the digital signal processing unit 23X. The optical modulator 26X outputs the optical signal generated by optical modulation to the IF unit 22X.

[0051] The optical receiver 27X includes a photodetector 28X. The photodetector 28X is, for example, a PD (Photo Diode), which receives the optical signal output from the IF unit 22X and converts the received optical signal into an electrical signal, for example, by performing light intensity detection. The photodetector 28X outputs the electrical signal obtained from the optical signal conversion as a received data signal to the digital signal processing unit 23X.

[0052] Optical communication device 2Y has the same functional units as optical communication device 2X. Hereinafter, when indicating the functional units of optical communication device 2Y, the “X” in the reference numerals used to indicate the functional units of optical communication device 2X will be replaced with “Y”.

[0053] The connection node device 1 includes an edge function unit 11 and an output port switching unit 14. The output port switching unit 14 includes, for example, optical switches 15T and 15R, which function as fiber patch panels. Optical switch 15T is connected to optical fiber 51T, the edge function unit 11, and optical fiber 52T in the optical transmission path 52. Optical switch 15T performs a switching process to change the connection destination of optical fiber 51T to either the edge function unit 11 or optical fiber 52T. Optical switch 15R is connected to optical fiber 51R, the edge function unit 11, and optical fiber 52R in the optical transmission path 52. Optical switch 15R performs a switching process to change the connection destination of optical fiber 51R to either the edge function unit 11 or optical fiber 52R.

[0054] The edge function unit 11 includes a control unit 12 and a connection information processing unit 13. The connection information processing unit 13 includes an IF unit 31, a digital signal processing unit 32, an optical receiver 33, an optical transmitter 35, and a connection information generation unit 38. The IF unit 31 connects the optical switch unit 15T to the optical receiver 33. The IF unit 31 also connects the optical switch unit 15R to the optical transmitter 35.

[0055] The optical receiver 33 includes an optical receiver 34. The optical receiver 34 is, for example, a PD, which receives the optical signal output from the IF unit 31 and converts the received optical signal into an electrical signal, for example, by performing light intensity detection. The optical receiver 34 outputs the electrical signal obtained from the conversion of the optical signal as a received data signal to the digital signal processing unit 32.

[0056] The transmitting unit 35 includes a single-wavelength light source 36 and an optical modulator 37. The single-wavelength light source 36 generates and outputs continuous light of a predetermined single wavelength with a basic output optical power specified by the control unit 12 for a basic mode. Here, the basic mode refers to a transmission mode predetermined based on a predetermined basic output optical power, basic modulation method, basic wavelength, etc. The control unit 12, the control unit 71X of the optical communication device 2X, and the control unit 71Y of the optical communication device 2Y pre-store information related to the basic mode in their internal storage areas.

[0057] The wavelengths of the single-wavelength light source 36, the single-wavelength light source 25X of the optical communication device 2X, and the single-wavelength light source 25Y of the optical communication device 2Y are all fundamental wavelengths predetermined in the basic mode. However, these wavelengths are not necessarily limited to the same fundamental wavelength value. The wavelengths of the single-wavelength light source 36 and the single-wavelength light source 25Y of the optical communication device 2Y only need to be within the range that the photodetector 28X of the optical communication device 2X can receive. In addition, the wavelength of the single-wavelength light source 25X of the optical communication device 2X only needs to be within the range that the photodetector 28Y of the optical communication device 2Y and the photodetector 34 of the connection node device 1 can receive.

[0058] The optical modulator 37 modulates the continuous light output by the single-wavelength light source 36 according to the basic modulation method of the basic mode specified by the control unit 12, based on the transmission data signal output by the digital signal processing unit 32.

[0059] The digital signal processing unit 32, for example a DSP, is connected to the optical receiver 33 and the optical transmitter 35. The digital signal processing unit 32 acquires the received data signal output from the optical receiver 34 of the optical receiver 33. If the received data signal output from the optical receiver 34 contains connection request data sent by the optical communication device 2X, the digital signal processing unit 32 reads and acquires the connection request data from the received data signal. Additionally, the digital signal processing unit 32 generates a transmit data signal and outputs it to the optical modulator 37.

[0060] The connection information generation unit 38 calculates and obtains the transmission path information of the optical fiber 51T of the optical transmission path 51 based on the received data signal obtained by the digital signal processing unit 32, for example, through the operation specified in Reference 1 below.

[0061] [Reference 1: Takeo Sasai, et al, "Simultaneous Detection of AnomalyPoints and Fiber Types in Multi-Span Transmission Links Only by Receiver-SideDigital Signal Processing", OFC 2020: 1-3]

[0062] Here, the transmission path information of the optical fiber 51T refers to information including the loss of the optical fiber 51T in the optical transmission path 51, the gain of the amplifier inserted into the optical transmission path 51, the NF (Noise Figure) of the amplifier, and the fiber type of the optical fiber 51T. The connection information generation unit 38 obtains the BER (Bit Error Rate) of the optical transmission path 51 acquired by the digital signal processing unit 32 from the received data signal, and generates connection information including the acquired BER of the optical transmission path 51 and the calculated transmission path information of the optical fiber 51T. Alternatively, the digital signal processing unit 32 may acquire information for calculating the BER instead of the BER, and the connection information generation unit 38 may calculate the BER based on the information for calculating the BER acquired by the digital signal processing unit 32, and include the calculated BER in the connection information. Alternatively, the digital signal processing unit 32 can be configured to acquire, in addition to BER, Q-value (Quality Factor), PMD (Polarization Mode Dispersion), CD (Chromatic Dispersion), and OSNR (Optical Signal-to-Noise Ratio), and output this information to the connection information generation unit 38, thereby including Q-value, PMD, CD, and OSNR in the connection information. The digital signal processing unit 32 transmits electrical signals to the optical modulator 37. The connection information generation unit 38 outputs the connection request data read from the received data signal by the digital signal processing unit 32 and the generated connection information to the control unit 12.

[0063] The control unit 12 pre-stores a path information table in its internal storage area. This path information table is obtained by associating the address information of the optical transmitting and receiving units 21X and 21Y of the optical communication devices 2X and 2Y connected to the connection node device 1 with identification information used to determine the optical transmission path corresponding to that address information. Alternatively, the control unit 12 may not pre-store the path information table in its internal storage area, but may retrieve it from external devices or the like as needed. For example, in the case of the optical transmission system 100, the path information table associates the address information of the optical transmitting and receiving unit 21X of the optical communication device 2X with identification information used to determine the optical transmission path 51, and the address information of the optical transmitting and receiving unit 21Y of the optical communication device 2Y with identification information used to determine the optical transmission path 52.

[0064] The control unit 12 refers to the path information table to detect the identification information used to determine the optical transmission path 52 corresponding to the connection destination address information contained in the connection request data output by the digital signal processing unit 32. However, in the first embodiment, the path information table associates the address information of the optical transmitter / receiver unit 21Y with the identification information used to determine the optical transmission path 52, and the optical communication device 2X is a structure that selects only the optical transmitter / receiver unit 21Y as the connection destination. Therefore, the control unit 12 always detects the identification information used to determine the optical transmission path 52, and the following description assumes that the control unit 12 detects the identification information used to determine the optical transmission path 52.

[0065] The control unit 12 stores the transmission path information of the optical transmission path 52 in its internal storage area in a manner that associates it with the identification information used to determine the optical transmission path 52. Here, similar to the case of the optical transmission path 51 described above, the transmission path information of the optical transmission path 52 refers to information including the loss of the optical fibers 52T and 52R provided in the optical transmission path 52, the gain of the amplifier inserted into the optical transmission path 52, the NF of the amplifier, and the type of the optical fibers 52T and 52R. Furthermore, the control unit 12 may also pre-calculate the transmission path information of the optical transmission path 52 based on the optical signal transmitted through the optical transmission path 52 using a predetermined calculation and store it in its internal storage area, or it may retrieve it from an external device as needed at specific times, such as during network deployment. Alternatively, the transmission path information of the optical transmission path 52 may also be pre-calculated using methods other than the predetermined calculation.

[0066] The control unit 12 stores information about the available resources of the optical transmission path 52 in its internal storage area. Here, the information about available resources refers to, for example, information about wavelengths, wavelength ranges, or optical transmission paths not used in communication when determining the availability of resources. Furthermore, the information about available resources is updated by the control unit 12 whenever a communication path is established. Based on the connection information generated by the connection information generation unit 38 and the transmission path information of the optical transmission path 52 stored in its internal storage area, the control unit 12 calculates the transmission path characteristics (QoT - Quality of Transmission) using, for example, an internal transmission design tool. Here, the transmission design tool may be, for example, GNPy (Gaussian Noise model in Python) as shown in Reference 2 below.

[0067] [Reference 2: Alessio Ferrari, et al, "The GNPy Open Source Library ofApplications for Software Abstraction of WDM Data Transport in Open OpticalNetworks", 2020 6th IEEE International Conference on Network Softwarization (NetSoft), DOI: 10.1109 / NetSoft48620.2020.9165313, June 2020]

[0068] Here, transmission path characteristics refer to values ​​such as OSNR, GSNR (Generalized Signal-to-Noise Ratio), Q value, and BER calculated by transmission design tools. However, the OSNR, GSNR, Q value, and BER information calculated by the transmission design tools here includes the overall OSNR, GSNR, Q value, and BER information of the optical transmission paths 51 and 52.

[0069] The control unit 12 selects configuration information for determining the transmission mode through a predetermined selection process based on the calculated transmission path characteristics, information on the available resources of the optical transmission path 52 stored in its internal storage area, the desired bit rate information contained in the connection request data obtained from the digital signal processing unit 32, and the specification information of the optical transceiver unit 21X. This predetermined selection process is performed as follows: For example, based on the FEC type contained in the specification information of the optical transceiver unit 21X, the FEC type usable in both the optical transceiver unit 21X and the optical transceiver unit 21Y is selected. After selecting the FEC type, the threshold of the ONSR determined for the modulation scheme contained in the specification information of the optical transceiver unit 21X is compared with the calculated OSNR of the transmission path characteristics, and a modulation scheme with an OSNR threshold greater than or equal to the calculated OSNR of the transmission path characteristics is selected. The configuration information is selected by a process that selects a combination of modulation schemes and baud rates that can be transmitted at bit rates greater than or equal to the bit rates shown in the desired bit rate information from among the candidate bit rates of several selected modulation schemes. The transmission mode is determined by the configuration information selected by the control unit 12. Here, the configuration information used to determine the transmission mode refers to information such as output optical power and permitted signal bandwidth, in addition to the modulation scheme, baud rate, bit rate, and FEC (Forward Error Correction) type selected in the above-described process. Furthermore, the FEC type information available to the optical transceiver unit 21Y is either pre-acquired by the control unit 12 and stored in its internal storage area, or acquired from the optical transceiver unit 21Y or an external device as needed. Alternatively, in the aforementioned selection process, a combination of modulation scheme and baud rate can be selected that allows transmission at a bit rate higher than or equal to the bit rate shown in the desired bit rate information from among the candidate bit rates of the selected modulation schemes.

[0070] The control unit 12 generates transmission mode information that includes the selected configuration information and the connection party address information contained in the connection request data. The control unit 12 outputs the generated transmission mode information to the digital signal processing unit 32. The control unit 12, as follows... Figure 1 As shown, for example, it is connected to the control unit 20Y of the optical communication device 2Y via connection line 3, and sends the generated transmission mode information to the control unit 20Y of the optical communication device 2Y. The control unit 12 outputs control signals (hereinafter referred to as "switching indication signals") to the optical switch units 15T and 15R of the output port switching unit 14 to indicate the switching process for switching the connection destination.

[0071] (Processing performed by the optical transmission system of the first embodiment)

[0072] Figure 3 This is a flowchart illustrating the processing flow performed by the optical transmission system 100. For example... Figure 2 As shown, in the initial state, the output port switching unit 14 of the connection node device 1 sets the connection destination of the optical transmission path 51 to the connection information processing unit 13 provided by the connection node device 1. More specifically, the optical switch unit 15T connects the optical fiber 51T to the optical receiver 34 via the IF unit 31, and the optical switch unit 15R connects the optical fiber 51R to the optical modulator 37 via the IF unit 31.

[0073] The control unit 20X of the optical communication device 2X generates a connection request indication signal containing address information and desired bit rate of the optical transceiver unit 21Y, for connection to the optical transceiver unit 21Y of the optical communication device 2Y. The control unit 20X outputs the generated connection request indication signal to the control unit 71X of the optical transceiver unit 21X. The control unit 71X acquires the connection request indication signal output by the control unit 20X and sets the address information of the optical transceiver unit 21Y contained in the acquired connection request indication signal as the connection destination address information. The control unit 71X sets the address information of the optical transceiver unit 21X stored in its internal storage area as the connection party address information. The control unit 71X generates connection request data containing the connection destination address information, the connection party address information, the desired bit rate contained in the connection request indication signal, and the specification information of the optical transceiver unit 21X stored in its internal storage area.

[0074] The control unit 71X outputs an output optical power specification signal, representing the basic output optical power predetermined in the basic mode, to the single-wavelength light source 25X. The single-wavelength light source 25X generates and outputs continuous light of a predetermined wavelength at the basic output optical power specified by the output optical power specification signal received from the control unit 71X. The control unit 71X outputs a modulation mode specification signal, representing the basic modulation mode predetermined in the basic mode, to the optical modulator 26X. The optical modulator 26X begins optical modulation according to the basic modulation mode specified by the modulation mode specification signal received from the control unit 71X.

[0075] The control unit 71X outputs the generated connection request data to the digital signal processing unit 23X. The digital signal processing unit 23X obtains the connection request data output by the control unit 71X and generates a transmission data signal by including the obtained connection request data in the idle area of ​​the transmission frame overhead. The digital signal processing unit 23X outputs the generated electrical signal transmission data signal to the optical modulator 26X. The optical modulator 26X performs optical modulation on the continuous light output by the single-wavelength light source 25X based on the transmission data signal containing the connection request data output by the digital signal processing unit 23X. The optical modulator 26X sends the optical signal generated by optical modulation to the optical fiber 51T via the IF unit 22X. The optical fiber 51T transmits the optical signal to the optical switch unit 15T of the output port switching unit 14 of the connection node device 1 (step S1).

[0076] Optical switch unit 15T receives the optical signal transmitted by optical fiber 51T and outputs the received optical signal to optical receiver 34 of optical receiver unit 33 via IF unit 31. Optical receiver 34 acquires the optical signal output by optical switch unit 15T. Optical receiver 34 converts the acquired optical signal into an electrical signal and sets it as a receive data signal. Optical receiver 34 outputs the receive data signal to digital signal processing unit 32. Digital signal processing unit 32 acquires the receive data signal output by optical receiver 34. Digital signal processing unit 32 reads the connection request data contained in the overhead region of the acquired receive data signal and outputs it to connection information generation unit 38. Digital signal processing unit 32 obtains the BER of optical transmission path 51 from the acquired receive data signal and outputs it to connection information generation unit 38. Connection information generation unit 38 acquires the connection request data and BER output by digital signal processing unit 32. When the connection information generation unit 38 obtains the connection request data and BER output by the digital signal processing unit 32, it calculates the transmission path information of the optical transmission path 51 based on the received data signal obtained and output by the digital signal processing unit 32 to the connection information generation unit 38. The connection information generation unit 38 generates connection information including the calculated transmission path information and BER of the optical transmission path 51. The connection information generation unit 38 outputs the obtained connection request data and the generated connection information to the control unit 12 (step S2).

[0077] The control unit 12 acquires the connection request data and connection information output by the connection information generation unit 38. The control unit 12 refers to a path information table stored in its internal storage area or a path information table acquired on demand to detect identification information corresponding to the connection destination address information (in this case, the address information of the optical transmitter / receiver unit 21Y) contained in the acquired connection request data, used to determine the optical transmission path 52. The control unit 12 reads and acquires the transmission path information of the optical transmission path 52 corresponding to the detected identification information from its internal storage area, or acquires the transmission path information of the optical transmission path 52 on demand. The control unit 12 calculates the transmission path characteristics based on the acquired transmission path information of the optical transmission path 52 and the acquired connection information (step S3).

[0078] Based on the calculated transmission path characteristics, the desired bit rate information included in the connection request data, and the specification information of the optical transmitter / receiver unit 21X, the control unit 12 selects configuration information through a predetermined selection process. The transmission mode is determined by the configuration information selected by the control unit 12. The control unit 12 generates transmission mode information that includes the selected configuration information and the connection address information included in the connection request data (step S4).

[0079] The control unit 12 sends the generated transmission mode information to the control unit 20Y of the optical communication device 2Y via the connection line 3 (step S5-1). The control unit 20Y of the optical communication device 2Y receives the transmission mode information sent by the control unit 12 of the connection node device 1, and outputs the received transmission mode information to the control unit 71Y of the optical transmission and reception unit 21Y. The control unit 71Y acquires the transmission mode information output by the control unit 20Y. The control unit 71Y outputs an output optical power specification signal, representing the output optical power shown in the acquired transmission mode information, to the single-wavelength light source 25Y. As a result, the single-wavelength light source 25Y generates and outputs continuous light at the output optical power specified by the output optical power specification signal, i.e., the output optical power shown in the transmission mode information.

[0080] The control unit 71Y outputs a modulation mode specification signal, indicating the modulation mode shown in the transmission mode information, to the optical modulator 26Y. The optical modulator 26Y then performs optical modulation using the modulation mode specified by the modulation mode specification signal received from the control unit 71Y, i.e., the modulation mode shown in the transmission mode information. The control unit 71Y outputs the transmission mode information to the digital signal processing unit 23Y. The digital signal processing unit 23Y obtains the transmission mode information output by the control unit 71Y and stores the modulation mode, baud rate, bit rate, FEC type, permitted signal bandwidth, etc., shown in the obtained transmission mode information as setting parameters in its internal storage area. When generating a transmission data signal, it generates the transmission data signal based on the setting parameters stored in the internal storage area and outputs it to the optical modulator 26Y (step S6-1). Alternatively, the control unit 71Y may store the modulation mode, baud rate, bit rate, FEC type, permitted signal bandwidth, etc., shown in the transmission mode information as setting parameters in its internal storage area. In this case, when the digital signal processing unit 23Y generates the transmission data signal, the control unit 71Y outputs the setting parameters to the digital signal processing unit 23Y.

[0081] The control unit 12 of the connection node device 1 outputs an output optical power specification signal to the single-wavelength light source 36 to specify the basic output optical power of the basic mode, and outputs a modulation scheme specification signal to the optical modulator 37 to specify the basic modulation scheme of the basic mode. The control unit 12 outputs the generated transmission mode information to the digital signal processing unit 32. The digital signal processing unit 32 obtains the transmission mode information output by the control unit 12 and generates a transmission data signal by including the obtained transmission mode information in the idle area of ​​the overhead of the transmission frame. The digital signal processing unit 32 outputs the generated electrical signal transmission data signal to the optical modulator 37. Based on the transmission data signal output by the digital signal processing unit 32, the optical modulator 37 modulates the continuous light output at the basic output optical power specified by the output optical power specification signal according to the basic modulation scheme of the basic mode specified by the modulation scheme specification signal.

[0082] The optical modulator 37 outputs the optical signal generated by optical modulation to the IF unit 31. The IF unit 31 acquires the optical signal output by the optical modulator 37. The IF unit 31 outputs the acquired optical signal to the optical switch unit 15R. The optical switch unit 15R sends the optical signal output by the IF unit 31 to the optical fiber 51R. The optical fiber 51R transmits the optical signal sent by the optical switch unit 15R to the IF unit 22X of the optical communication device 2X (step S5-2).

[0083] The IF section 22X of the optical communication device 2X receives the optical signal transmitted by the optical fiber 51R and outputs the received optical signal to the optical receiver 28X. The optical receiver 28X receives the optical signal output by the IF section 22X, converts the received optical signal into an electrical signal, and sets it as a received data signal. The optical receiver 28X outputs the received data signal to the digital signal processing unit 23X. The digital signal processing unit 23X acquires the received data signal output by the optical receiver 28X.

[0084] The digital signal processing unit 23X reads transmission mode information from the overhead region of the acquired received data signal and outputs the read transmission mode information to the control unit 71X. The control unit 71X receives the transmission mode information output by the digital signal processing unit 23X. If the connection address information included in the received transmission mode information is not the address information attached to the optical transceiver unit 21X stored in its internal storage region, the control unit 71X discards the received transmission mode information. Conversely, if the address information included in the received transmission mode information matches the address information attached to the optical transceiver unit 21X, the control unit 71X outputs an output optical power specification signal, representing the output optical power shown in the read transmission mode information, to the single-wavelength light source 25X. Thus, the single-wavelength light source 25X generates and outputs continuous light at the output optical power specified by the output optical power specification signal, i.e., the output optical power shown in the transmission mode information.

[0085] The control unit 71X outputs a modulation scheme specification signal, indicating the modulation scheme shown in the transmission mode information, to the optical modulator 26X. Consequently, the optical modulator 26X performs optical modulation using the modulation scheme specified by the modulation scheme specification signal received from the control unit 71X, i.e., the modulation scheme shown in the transmission mode information. The digital signal processing unit 23X stores the modulation scheme, baud rate, bit rate, FEC type, permitted signal band, etc., shown in the read transmission mode information as setting parameters in its internal storage area beforehand. When generating a transmission data signal, it generates the transmission data signal based on the setting parameters stored in the internal storage area and outputs it to the optical modulator 26X (step S6-2). Alternatively, the control unit 71X may store the modulation scheme, baud rate, bit rate, FEC type, permitted signal band, etc., shown in the transmission mode information as setting parameters in its internal storage area beforehand. In this case, the control unit 71X outputs the setting parameters to the digital signal processing unit 23X when the digital signal processing unit 23X generates the transmission data signal.

[0086] The control unit 12 of the connection node device 1 refers to the path information table to detect the identification information for determining the optical transmission path 51, which corresponds to the address information of the connection party included in the generated transmission mode information (here, the address information of the optical transmitter / receiver unit 21X). Based on the detected identification information for determining the optical transmission path 51 and the identification information for determining the optical transmission path 52 detected in step S3, the control unit 12 performs a switching process to connect the optical transmission path 51 and the optical transmission path 52. The control unit 12 outputs a switching indication signal to the optical switch unit 15T of the output port switching unit 14 to set the connection destination of the optical fiber 51T to the optical fiber 52T. The control unit 12 outputs a switching indication signal to the optical switch unit 15R to set the connection destination of the optical fiber 51R to the optical fiber 52R.

[0087] When the optical switch unit 15T receives a switching indication signal from the control unit 12, it connects optical fiber 51T to optical fiber 52T. When the optical switch unit 15R receives a switching indication signal from the control unit 12, it connects optical fiber 51R to optical fiber 52R (step S7). Thus, as... Figure 4 As shown, optical fibers 51T and 52T are connected via optical switch 15T, and optical fibers 51R and 52R are connected via optical switch 15R. Therefore, the optical transmitter / receiver unit 21X of the optical communication device 2X and the optical transmitter / receiver unit 21Y of the optical communication device 2Y are connected via optical transmission path 51 and optical transmission path 52.

[0088] Furthermore, the processing order of steps S5-1 and S5-2 can be parallel, or in the order of steps S5-1 and S5-2, or in the reverse order.

[0089] In the structure of the first embodiment described above, the connection information processing unit 13 acquires connection information including transmission path information, which is information related to the optical transmission path. The output port switching unit 14 is connected to the optical transmission path 51 (which is the first optical transmission path), the optical transmission path 52 (which is the second optical transmission path), and the connection information processing unit 13, and initially sets the connection destination of the optical transmission path 51 to the connection information processing unit 13. The control unit 12 sends transmission mode information through the optical transmission path 51 to the optical transmission and reception unit 21X of the optical communication device 2X connected to the optical transmission path 51. This transmission mode information represents a transmission mode determined based on the connection information of the optical transmission path 51 acquired by the connection information processing unit 13 from the optical signal sent by the optical transmission and reception unit 21X, the connection request data sent by the optical transmission and reception unit 21X in a manner included in the optical signal, and the transmission path information of the optical transmission path 52. As an example, after the control unit 12 sends the transmission mode information, the output port switching unit 14 performs a switching process to switch the connection destination of the optical transmission path 51 from the connection information processing unit 13 to the optical transmission path 52. Therefore, for example, when an optical communication device 2Y equipped with an optical transmitter / receiver unit 21Y is connected to an optical transmission path 52, when connecting the optical transmitter / receiver units 21X and 21Y of optical communication devices 2X and 2Y to each other via multiple optical transmission paths 51 and 52, the connection can be made through the optical path of the optimal transmission mode without manual intervention. Thus, the cost and time required for setting the optical path can be reduced.

[0090] Furthermore, in the first embodiment described above, the control unit 12 of the connection node device 1 calculates the End-to-End transmission path characteristics, i.e., the transmission path characteristics between the end connected to the optical communication device 2X of the optical transmission path 51 and the end connected to the optical communication device 2Y of the optical transmission path 52, based on the connection information generated by the connection information processing unit 13 and the transmission path information of the optical transmission path 52. Alternatively, the transmission path characteristics can be calculated as follows: The control unit 12 calculates the transmission path characteristics of the optical transmission path 51 based on the connection information generated by the connection information processing unit 13. The control unit 12 calculates the transmission path characteristics of the optical transmission path 52 based on the transmission path information of the optical transmission path 52. Alternatively, the control unit 12 can calculate the approximate End-to-End transmission path characteristics based on the calculated transmission path characteristics of the optical transmission path 51 and the transmission path characteristics of the optical transmission path 52. For example, if the transmission path characteristics include OSNR and GSNR, the control unit 12 calculates the OSNR and GSNR of the optical transmission path 51 and the OSNR and GSNR of the optical transmission path 52. The control unit 12 calculates the estimated end-to-end OSNR based on the calculated OSNR of optical transmission path 51 and optical transmission path 52. Additionally, it calculates the estimated end-to-end GSNR based on the calculated GSNR of optical transmission path 51 and optical transmission path 52. Alternatively, the control unit 12 may not calculate the transmission path characteristics of optical transmission path 52 based on the transmission path information of optical transmission path 52, but may instead be configured as follows: The control unit 12 calculates the transmission path characteristics of optical transmission path 52 in advance based on the prior transmission path information of optical transmission path 52, and stores the calculated transmission path characteristics of optical transmission path 52 in an internal storage area. Alternatively, when processing the calculation of the transmission path characteristics of optical transmission path 52, the control unit 12 may instead read the transmission path characteristics of optical transmission path 52 from the internal storage area to obtain the transmission path characteristics of optical transmission path 52.

[0091] (Second Implementation)

[0092] Figure 5This is a block diagram showing the structure of the optical transmission system 101 in the second embodiment. In the second embodiment, the same reference numerals are used for structures identical to those in the first embodiment; the different structures will be described below. The optical transmission system 101 includes a connection node device 1a, an optical communication device 2X, multiple optical communication devices 2Y-1 to 2Y-n, an operation device 4, an optical transmission path 51, optical transmission paths 52-1 to 52-n, a connection line 3, and connection lines 3-1 to 3-n connecting the operation device 4 to each of the optical communication devices 2Y-1 to 2Y-n. Here, n is an integer greater than or equal to 1. The optical transmission path 51 connects the optical communication device 2X to the connection node device 1a. The optical transmission paths 52-1 to 52-n connect each of the optical communication devices 2Y-1 to 2Y-n to the connection node device 1a. The connection line 3 connects the operation device 4 to the connection node device 1a.

[0093] Each of the optical communication devices 2Y-1 to 2Y-n has the same structure as the optical communication device 2Y of the first embodiment, that is, the same structure as the optical communication device 2X. Hereinafter, when indicating the functional units included in the optical communication devices 2Y-1 to 2Y-n, the “X” in the reference numerals indicating the functional units included in the optical communication device 2X will be replaced with “Y-1” to “Yn” respectively. Similar to the optical transmission and reception unit 21X of the optical communication device 2X, each optical transmission and reception unit 21Y-1 to 21Y-n of the optical communication devices 2Y-1 to Yn is also pre-loaded with address information capable of identifying each optical transmission and reception unit.

[0094] Each optical transmission path 52-1 to 52-n, like the optical transmission path 52 of the first embodiment, has two optical fibers. The two optical fibers in each path are indicated by the reference numerals "T" and "R". For example, in the case of optical transmission path 52-1, they are represented as optical fibers 52T-1 and 52R-1. Connection lines 3-1 to 3-n are the same communication lines as connection line 3.

[0095] The connection node device 1a includes an edge function unit 11a and an output port switching unit 14. The output port switching unit 14 is connected to the optical transmission path 51, the connection information processing unit 13 of the connection node device 1a, and each of the optical transmission paths 52-1 to 52-n. It selects any one of the connection information processing unit 13 and the optical transmission paths 52-1 to 52-n as the connection destination of the optical transmission path 51 and switches the connection destination.

[0096] The edge function unit 11a includes a connection information processing unit 13 and a control unit 12a. The control unit 12a pre-stores an address path mapping table in its internal storage area. This address path mapping table is obtained by associating the address information of the optical transmission and receiving units 21X, 21Y-1 to 21Y-n of each optical communication device 2X, 21Y-1 to 21Y-n connected to the connection node device 1a with identification information for determining the optical transmission paths 51, 52-1 to 52-n connected to each corresponding optical transmission and receiving unit 21X, 21Y-1 to 21Y-n. Alternatively, the control unit 12a may not pre-store the address path mapping table in its internal storage area, but instead retrieve the address path mapping table from an external device as needed.

[0097] The control unit 12a transmits the connection information and connection request data output by the connection information generation unit 38 of the connection information processing unit 13 to the operating device 4 via the connection line 3. The control unit 12a outputs the transmission mode information received from the operating device 4 to the digital signal processing unit 32. The control unit 12a outputs a switching indication signal to the output port switching unit 14 to switch the connection destination.

[0098] The operating device 4 includes a path detection unit 41 and a transmission path design unit 42. The path detection unit 41 has a path information table pre-stored in its internal storage area. This table associates the address information of the optical transmitting and receiving units 21X, 21Y-1 to 21Y-n of the optical communication devices 2X, 2Y-1 to 2Y-n with identification information used to determine the optical transmission path corresponding to that address information. Alternatively, the path detection unit 41 may not pre-store the path information table in its internal storage area, but instead retrieve the path information table from an external device as needed.

[0099] For example, in the case of optical transmission system 101, in the path information table, for the address information of the optical transmitting and receiving units 21X, 21Y-1 to 21Y-n of each optical communication device 2X, 2Y-1 to 2Y-n, there is identification information for determining the optical transmission paths 51, 52-1 to 52-n connected to the optical transmitting and receiving units 21X, 21Y-1 to 21Y-n corresponding to each address information. The path detection unit 41 refers to the path information table to detect the identification information (here, i is any integer from 1 to n) for determining any one of the optical transmission paths 52-i among the optical transmission paths 52-1 to 52-n, corresponding to the connection destination address information included in the connection request data sent by the control unit 12a of the connection node device 1a.

[0100] The transmission path design unit 42 stores transmission path information for each optical transmission path 52-1 to 52-n in its internal storage area, associating it with identification information used to determine each optical transmission path 52-1 to 52-n. Alternatively, the transmission path design unit 42 can pre-calculate the transmission path information for each optical transmission path 52-1 to 52-n based on the optical signals transmitted through the optical transmission paths 52-1 to 52-n using a predetermined calculation and store it in its internal storage area. It can also retrieve the information from an external device as needed at specific times, such as during network deployment. Furthermore, the transmission path information for each optical transmission path 52-1 to 52-n can also be pre-calculated using methods other than the predetermined calculation.

[0101] The transmission path design unit 42 stores information about the available resources of each optical transmission path 52-1 to 52-n in its internal storage area. Here, the information indicating available resources refers to, for example, information about wavelengths, wavelength ranges, or optical transmission paths not used in communication when determining the availability of resources. Furthermore, the information indicating available resources is updated by the transmission path design unit 42 each time a communication path is established.

[0102] The transmission path design unit 42 calculates the transmission path characteristics using, for example, a transmission design tool such as GNPy, based on the connection information sent by the control unit 12a of the connection node device 1a and the transmission path information of the optical transmission path 52-i corresponding to the identification information of the optical transmission path 52-i detected by the path detection unit 41.

[0103] The transmission path design unit 42 selects configuration information through a predetermined selection process based on the calculated transmission path characteristics, information on idle resources corresponding to the identification information for determining the optical transmission path 52-i detected by the path detection unit 41, the expected bit rate information contained in the connection request data sent by the control unit 12a of the connection node device 1a, and the specification information of the optical transmit / receive unit 21X. The transmission mode is determined by the configuration information selected by the transmission path design unit 42. The transmission path design unit 42 generates transmission mode information that includes the selected configuration information and the connection address information contained in the connection request data. The transmission path design unit 42 sends the generated transmission mode information and the identification information for determining the optical transmission path 52-i detected by the path detection unit 41 to the control unit 12a of the connection node device 1a via the connection line 3.

[0104] The transmission path design unit 42 stores in its internal storage area a connection line table that associates the address information of the optical transmitting / receiving units 21Y-1 to 21Y-n of the optical communication devices 2Y-1 to 2Y-n with the connection lines 3-1 to 3-n corresponding to the optical communication devices 2Y-1 to 2Y-n containing the address information. Referring to the connection line table stored in its internal storage area, the transmission path design unit 42 sends the generated transmission mode information to the control units 20Y-1 to 20Y-n of the optical communication devices 2Y-1 to 2Y-n via the connection lines 3-1 to 3-n that connect the optical transmitting / receiving units 21Y-1 to 21Y-n containing the connection destination address information included in the connection request data.

[0105] (Processing performed by the optical transmission system of the second embodiment)

[0106] Figure 6 This is a flowchart illustrating the process performed by the optical transmission system 101 of the second embodiment. Hereinafter, as an example, the process by which the optical transmission / reception unit 21X of the optical communication device 2X connects to the optical transmission / reception unit 21Y-i of the optical communication device 2Y-i as a connection destination will be described. Figure 6 The processing of steps Sa1 and Sa2 is the same as that of steps S1 and S2 in the first embodiment. However, in step Sa1, the control unit 20X of the optical communication device 2X generates a connection request indication signal in a manner that includes the address information of the optical transmission and reception unit 21Y-i of the optical communication device 2Y-i as the address information of the connection destination, and the optical communication device 2Y-i is connected to the optical transmission path 52-i and the connection line 3-i.

[0107] The control unit 12a acquires the connection request data and connection information output by the connection information generation unit 38. The control unit 12a then transmits the acquired connection request data and connection information to the operation device 4 via the connection line 3 (step Sa3).

[0108] The path detection unit 41 of the operating device 4 receives the connection request data sent by the control unit 12a. The path detection unit 41 refers to a path information table stored in its internal storage area or a path information table obtained as needed, and detects the identification information for determining the optical transmission path 52-i, which corresponds to the connection destination address information contained in the received connection request data (in this case, the address information of the optical transmission receiver 21Y-i). The path detection unit 41 outputs the detected identification information for determining the optical transmission path 52-i to the transmission path design unit 42 (step Sa4).

[0109] The transmission path design unit 42 receives connection information and connection request data sent by the control unit 12a. The transmission path design unit 42 obtains the identification information output by the path detection unit 41 for determining the optical transmission path 52-i. The transmission path design unit 42 reads from its internal storage area and acquires the transmission path information of the optical transmission path 52-i corresponding to the acquired identification information for determining the optical transmission path 52-i, or acquires the transmission path information of the optical transmission path 52-i as needed. The transmission path design unit 42 calculates the transmission path characteristics based on the acquired transmission path information of the optical transmission path 52-i and the received connection information (step Sa5).

[0110] Based on the calculated transmission path characteristics, the desired bit rate information contained in the received connection request data, and the specification information of the optical transmitter / receiver unit 21X, the transmission path design unit 42 selects configuration information through a prescribed selection process. The transmission mode is determined by the configuration information selected by the transmission path design unit 42. The transmission path design unit 42 generates transmission mode information containing the selected configuration information and the connection address information contained in the connection request data (step Sa6).

[0111] The transmission path design unit 42, referring to the connection line table stored in its internal storage area, sends the generated transmission mode information to the control unit 20Y-i of the optical communication device 2Y-i via connection line 3-i, which is connected to the optical transmission and reception unit 21Y-i corresponding to the connection destination address information included in the connection request data (step Sa7-1). The control unit 20Y-i of the optical communication device 2Y-i receives the transmission mode information sent by the transmission path design unit 42 of the operation device 4 and outputs the received transmission mode information to the control unit 71Y-i of the optical transmission and reception unit 21X-i. Thereafter, the functional units of the optical communication device 2Y-i corresponding to the functional units of the optical communication device 2Y in the first embodiment perform the same processing as step S6-1 in the first embodiment (step Sa8-1).

[0112] The transmission path design unit 42 sends the generated transmission mode information and the identification information for determining the optical transmission path 52-i detected by the path detection unit 41 to the connection node device 1a via the connection line 3 (step Sa7-2). The control unit 12a of the connection node device 1a receives the transmission mode information and the identification information for determining the optical transmission path 52-i sent by the transmission path design unit 42 of the operation device 4. After receiving the transmission mode information and the identification information for determining the optical transmission path 52-i, the control unit 12a, the connection information processing unit 13, and the output port switching unit 14 perform the same processing as step S5-2 of the first embodiment based on the received transmission mode information (step Sa8-2). Then, the same processing as step S6-2 of the first embodiment is performed (step Sa9).

[0113] The control unit 12a of the connection node device 1a detects identification information for determining the optical transmission path 51 from an address path mapping table stored in its internal storage area or from an address path mapping table obtained as needed, based on the connection address information included in the received transmission mode information and, in this case, the address information additional to the optical transmission receiver 21X. Based on the detected identification information for determining the optical transmission path 51 and the received identification information for determining the optical transmission path 52-i, the control unit 12a performs a switching process to connect the optical transmission path 51 to the optical transmission path 52-i. The control unit 12a outputs a switching indication signal to the optical switch unit 15T of the output port switching unit 14 to set the connection destination of the optical fiber 51T to the optical fiber 52T-i. The control unit 12a outputs a switching indication signal to the optical switch unit 15R to set the connection destination of the optical fiber 51R to the optical fiber 52R-i.

[0114] When the optical switch unit 15T receives a switching instruction signal from the control unit 12a, it connects optical fiber 51T to optical fiber 52T-i. When the optical switch unit 15R receives a switching instruction signal from the control unit 12a, it connects optical fiber 51R to optical fiber 52R-i (step Sa10). Thus, optical fibers 51T and 52T-i are connected via the optical switch unit 15T, and optical fibers 51R and 52R-i are connected via the optical switch unit 15R. Therefore, optical communication device 2X and optical communication device 2Y-i are connected via optical transmission path 51 and optical transmission path 52-i.

[0115] Furthermore, the processing order of steps Sa7-1 and Sa7-2 can be parallel, in the order of steps Sa7-1 and Sa7-2, or in the reverse order.

[0116] In the structure of the second embodiment described above, optical communication device 2X, which is a first optical communication device, is connected to connection node device 1a via optical transmission path 51, which is a first optical transmission path. Optical communication devices 2Y-1 to 2Y-n, which are second optical communication devices, are connected to connection node device 1a via optical transmission paths 52-1 to 52-n, which are second optical transmission paths. Operation device 4 is connected to each of the optical communication devices 2Y-1 to 2Y-n, which are connection node device 1a. The operating device 4 reads and obtains the transmission path information of the optical transmission path 52-i pre-stored in its internal storage area, or obtains the transmission path information of the optical transmission path 52-i as needed. Based on the obtained transmission path information of the optical transmission path 52-i, the connection information processing unit 13 of the connection node device 1a obtains the connection information of the optical transmission path 51 from the optical signal transmitted by the optical transmitter / receiver unit 21X of the optical communication device 2X, and the connection request data transmitted by the optical transmitter / receiver unit 21X of the optical communication device 2X in a manner included in the optical signal, it determines the transmission mode and sends the transmission mode information representing the determined transmission mode to the control unit 12a of the connection node device 1a and the optical transmitter / receiver unit 21Y-i of the optical communication device 2Y-i. The optical transmitter / receiver unit 21X of the optical communication device 2X receives the transmission mode information received from the operating device 4 by the control unit 12a of the connection node device 1a and sends it to the optical transmission path 51, and transmits and receives optical signals through the optical transmission path 51 in the transmission mode indicated by the received transmission mode information. The optical transmitter / receiver unit 21Y-i of the optical communication device 2Y-i transmits and receives optical signals via optical transmission path 52-i according to the transmission mode information received from the operation device 4. After the control unit 12a sends the transmission mode information to the optical communication device 2X via optical transmission path 51, the output port switching unit 14 of the connection node device 1a connects the optical transmitter / receiver unit 21X of the optical communication device 2X and the optical transmitter / receiver unit 21Y-i of the optical communication device 2Y-i via optical transmission path 51 and optical transmission path 52 through a switching process. Therefore, when connecting the optical transmitter / receiver units 21X and 21Y-i of the optical communication devices 2X and 2Y-i via multiple optical transmission paths 51 and 52-i, the connection can be made via the optical path of the optimal transmission mode without manual intervention. This reduces the cost and time required for setting the optical path.

[0117] Furthermore, in the optical transmission system 101 of the second embodiment described above, it may be configured to replace the optical communication devices 2Y-1 to 2Y-n, and as... Figure 7The optical transmission system 101a shown includes an optical communication device 2cY with multiple optical transmitting and receiving units 21Y-1 to 21Y-n and a control unit 20aY. Multiple optical transmission paths 52-1 to 52-n are respectively connected to the optical transmitting and receiving units 21Y-1 to 21Y-n. Figure 5 In the optical transmission system 101 shown, the transmission path design unit 42, referring to the connection line table stored in its internal storage area, sends transmission mode information to the control units 20Y-1 to 20Y-n of the optical communication devices 2Y-1 to 2Y-n through connection lines 3-1 to 3-n corresponding to the connection destination address information contained in the transmission mode information. For this, in Figure 7 In the optical transmission system 101a shown, the transmission path design unit 42a of the operating device 4a appends the connection destination address information contained in the connection request data to the generated transmission mode information, and sends it to the control unit 20aY of the optical communication device 2cY via the connection line 3-1. Therefore, the transmission path design unit 42a does not need to pre-store the connection line table in its internal storage area.

[0118] Regarding the structure other than that described below, the control unit 20aY has the same structure as each of the control units 20Y-1 to 20Y-n. When each of the control units 20Y-1 to 20Y-n receives transmission mode information sent by the transmission path design unit 42a, it outputs the received transmission mode information to its respective connected optical transceiver unit 21Y-1 to 21Y-n. For this purpose, when the control unit 20aY receives transmission mode information sent by the transmission path design unit 42a via the connection line 3-1, it outputs the transmission mode information to any one of the optical transceiver units 21Y-1 to 21Y-n corresponding to the connection destination address information appended to the received transmission mode information.

[0119] With the above-described structure, in the optical transmission system 101a, similar to the optical transmission system 101, the connection destination address information of the connection request data is set as the address information of the optical transmitter / receiver unit 21Y-i that requests connection. Thus, the optical transmitter / receiver unit 21Y-i, which is connected to the optical transmitter / receiver unit 21Y-i corresponding to the connection destination address information, can transmit and receive optical signals under the same transmission mode between the optical transmitter / receiver unit 21X and the optical transmitter / receiver unit 21Y-i via the optical transmission paths 51 and 52-i.

[0120] (Third Implementation)

[0121] Figure 8This is a block diagram illustrating the structure of the optical transmission system 102 according to the third embodiment. In the third embodiment, the same reference numerals are used for structures identical to those in the first and second embodiments; the different structures will be described below. The optical transmission system 102 includes a connection node device 1b, an optical communication device 2aX, multiple optical communication devices 2bY-1 to 2bY-n, an operating device 4b, an optical transmission path 51, optical transmission paths 52-1 to 52-n, a connection line 3, and connection lines 3-1 to 3-n. The optical communication device 2aX is, for example, a communication device used by a user, and the optical communication devices 2bY-1 to 2bY-n are, for example, optical transmission devices owned by a telecommunications operator, i.e., node devices in a communication network, or white-box switches owned by a telecommunications operator or data center operator. The optical transmission path 51 connects the optical communication device 2aX to the connection node device 1b. The optical transmission paths 52-1 to 52-n connect each of the optical communication devices 2bY-1 to 2bY-n to the connection node device 1b. Connection line 3 connects the operating device 4b to the connection node device 1b. Connection lines 3-1 to 3-n connect the operating device 4b to each of the optical communication devices 2bY-1 to 2bY-n.

[0122] Not only referencing Figure 8 Moreover, refer to Figure 9 The internal structure of the connecting node device 1b, the optical communication device 2aX, the optical communication devices 2bY-1 to 2bY-n, and the operating device 4b will be explained below. Furthermore, Figure 8 and Figure 9 In the connecting lines shown, the thick dotted lines represent the wavelength path of the fundamental wavelength, and the thick dashed lines represent wavelength paths other than the fundamental wavelength. The arrows on the thick dotted lines indicate the light data signals transmitted along the wavelength path of the fundamental wavelength.

[0123] like Figure 8 As shown, the optical communication device 2aX includes multiple optical transmission and reception units 21aX-1 to 21aX-m, a wavelength division multiplexing separation unit 6aX, a control unit 20aX, and a transmission control unit 29X. Here, m is an integer of 1 or more, which can be the same as n or a different value from n.

[0124] The control unit 20aX is connected to each of the optical transmit / receive units 21aX-1 to 21aX-m, and performs control over each of the optical transmit / receive units 21aX-1 to 21aX-m, as well as input and output of information between the control unit 20aX-1 to 21aX-m. Furthermore, when the control unit 20aX initiates a connection to any one of the optical transmit / receive units 21aY-1 to 20aY-n in each of the optical communication devices 2bY-1 to 2bY-n, it generates a connection request indication signal.

[0125] like Figure 9 As shown, the optical transceiver unit 21aX-1 includes an IF unit 22X-1, an optical transceiver unit 24aX-1, an optical receiver unit 27X-1, a digital signal processing unit 23aX-1, and a control unit 71aX-1. The IF unit 22X-1 connects the optical transceiver unit 24aX-1 to the optical fiber 51T via the wavelength division multiplexing unit 8aX included in the wavelength division multiplexing demultiplexer unit 6aX. The IF unit 22X-1 connects the optical receiver unit 27X-1 to the optical fiber 51R via the wavelength separation unit 7aX included in the wavelength division multiplexing demultiplexer unit 6aX.

[0126] For example, when starting to connect to any one of the optical transmission and reception units 21aY-1 to 21aY-n provided in the optical communication devices 2bY-1 to 2bY-n, the control unit 71aX-1 receives a connection request indication signal from the control unit 20aX and generates connection request data for requesting a connection using an electrical signal. In the connection request data of the third embodiment, the specification information of the optical transmission and reception unit 21aX-1 includes, for example, not only the modulation method, FEC type, and baud rate that can be used in the optical transmission unit 24aX-1, but also information such as whether the wavelength-variable light source 25aX-1 provided in the optical transmission unit 24aX-1 outputs by changing the wavelength, and information indicating the range of wavelengths that the wavelength-variable light source 25aX-1 can generate, i.e., the wavelength range of the wavelength-variable light source 25aX-1.

[0127] Address information for identifying each optical transmitter / receiver unit is pre-attached to the optical transmitter / receiver units 21aX-1 to 21aX-m of the optical communication device 2aX and the optical transmitter / receiver units 21aY-1 to 21aY-n of the optical communication devices 2bY-1 to 2bY-n. The control unit 20aX pre-stores the desired bit rate and the address information of the connection destination in its internal storage area. The control unit 71aX-1 of the optical transmitter / receiver unit 21aX-1 pre-stores the address information attached to the optical transmitter / receiver unit 21aX-1 equipped with the control unit 71aX-1 in its internal storage area. For example, when the optical transmitter / receiver unit 21aX-1 is configured to the optical communication device 2aX, the control unit 71aX-1 obtains the specification information of the optical transmitter / receiver unit 21aX-1 from the optical transmitter unit 24aX-1 and the digital signal processing unit 23aX-1 and stores it in its internal storage area. Furthermore, the control unit 20aX does not pre-store the address information of the connection destination in its internal storage area. For example, it can be configured to obtain and acquire the address information of the connection destination specified by the user of the optical communication device 2aX, or it can be configured to obtain the address information of the connection destination from the connection node device 1b. Additionally, the control unit 20aX does not pre-store the desired bit rate in its internal storage area; it can also be configured to accept user input operations to obtain and acquire data of the bit rate pre-specified by the user.

[0128] For example, when the control unit 20aX requests a connection from the optical transceiver unit 21aX-1 to the optical transceiver unit 21aY-i of the optical communication device 2aY-i, it generates a connection request indication signal containing the address information of the optical transceiver unit 21aY-i and the desired bit rate, and outputs it to the control unit 71aX-1 of the optical transceiver unit 21aX-1. The control unit 71aX-1 reads the address information of the optical transceiver unit 21aY-i contained in the connection request indication signal received from the control unit 20aX and sets it as the connection destination address information, and reads the address information of the optical transceiver unit 21aX-1 stored in its internal storage area and sets it as the connection party address information. The control unit 71aX-1 generates connection request data containing the connection destination address information and the connection party address information, the desired bit rate contained in the connection request indication signal, and the specification information of the optical transceiver unit 21aX-1 stored in its internal storage area. The control unit 71aX-1 outputs the generated connection request data to the digital signal processing unit 23aX-1.

[0129] The control unit 71aX-1 collects optical input information, such as the transceiver type and number of transceivers provided by the optical transceiver unit 21aX-1, which includes pre-collected information such as the wavelength division multiplexing number, Output-Power, and TxOSNR of the optical transceiver unit 24aX-1, as shown in Patent Document 2. The control unit 71aX-1 outputs the collected optical input information to the digital signal processing unit 23aX-1.

[0130] The optical transmitting unit 24aX-1 includes a wavelength-variable light source 25aX-1 and an optical modulator 26X-1. The wavelength-variable light source 25aX-1 generates continuous light with an output optical power specified by an output optical power specification signal output from the control unit 71aX-1 and continuous light with a wavelength specified by a control signal (hereinafter referred to as the "wavelength specification signal") for an electrical signal for specifying the wavelength output from the control unit 71aX-1. The wavelength-variable light source 25aX-1 outputs the generated continuous light to the optical modulator 26X-1.

[0131] In addition to the structure of the digital signal processing unit 23X of the first embodiment, the digital signal processing unit 23aX-1 also has the following structure. When transmitting optical input information output by the transmission control unit 71aX-1 via the transmission data signal, the digital signal processing unit 23aX-1 generates a transmission data signal in a manner that includes the optical input information in the communication channel of the transmission frame.

[0132] The optical modulator 26X-1 has the same structure as the optical modulator 26X of the first embodiment. The optical receiver 27X-1 has the same structure as the optical receiver 27X of the first embodiment. The optical transmitters and receivers 21aX-2 to 21aX-m, other than the optical transmitter and receiver 21aX-1, have the same structure as the optical transmitter and receiver 21aX-1. Hereinafter, when indicating the functional units of each of the optical transmitters and receivers 21aX-2 to 21aX-m, the branch number "-1" of the reference numerals for each functional unit of the optical transmitter and receiver 21aX-1 will be replaced with their respective branch numbers "-2" to "-m". For example, in the case of the optical transmitter and receiver 21aX-2, it will be indicated as the digital signal processing unit 23aX-2.

[0133] The transmission control unit 29X is connected to each of the optical transmission and reception units 21aX-1 to 21aX-m, and outputs a timing signal indicating the timing of transmitting connection request data to each of the optical transmission and reception units 21aX-1 to 21aX-m. Each of the optical transmission and reception units 21aX-1 to 21aX-m transmits connection request data through the wavelength path 61-B of the fundamental wavelength. Therefore, if the optical transmission and reception units 21aX-1 to 21aX-m are not configured to transmit connection request data at different times, connection request data conflicts may occur. To avoid this conflict, the transmission control unit 29X outputs timing signals to the optical transmission and reception units 21aX-1 to 21aX-m, enabling the timing of the transmission of connection request data by each of the optical transmission and reception units 21aX-1 to 21aX-m to be different. Furthermore, the process by which the connection node device 1b connects to the multiple optical transmission and reception units 21aX-1 to 21aX-m using the fundamental wavelength employs, for example, the techniques disclosed in Patent Documents 1 and 2.

[0134] Optical communication device 2bY-1 includes an optical transmission and reception unit 21aY-1 and a control unit 20Y-1. The optical transmission and reception unit 21aY-1 has the same structure as the optical transmission and reception unit 21aX-1. Hereinafter, when indicating the functional units of the optical transmission and reception unit 21aY-1, the branch number "X-1" in the reference numerals of each functional unit of the optical transmission and reception unit 21aX-1 will be replaced with "Y-1". Optical communication devices 2bY-2 to 2bY-n, other than optical communication device 2bY-1, have the same structure as optical communication device 2bY-1. When indicating the functional units of optical communication devices 2Y-2 to 2Y-n, the "-1" in the reference numerals indicating the functional units of optical communication device 2bY-1 will be replaced with "-2" to "-n".

[0135] The connection node device 1b includes an edge function unit 11b and an output port switching unit 14a. The output port switching unit 14a includes optical switch units 15aT and 15aR (such as a WSS (Wavelength Selective Switch) or a fiber patch panel), a wavelength separation unit 7a, and a wavelength division multiplexing unit 8a. The wavelength separation unit 7a connects optical fiber 51T to the optical switch unit 15aT, performs wavelength division multiplexing on the optical signal in optical fiber 51T, and outputs the resulting optical signals to the optical switch unit 15aT. The wavelength division multiplexing unit 8a connects optical fiber 51R to the optical switch unit 15aR, performs wavelength division multiplexing on the optical signals of different wavelengths output from the optical switch unit 15aR, and sends the wavelength division multiplexed optical signal to optical fiber 51R.

[0136] Alternatively, the connection node device 1b can be configured such that the wavelength separation unit 7a and the wavelength division multiplexing unit 8a are located outside the output port switching unit 14a, the wavelength separation unit 7a is connected to the optical fiber 51T and the optical switch unit 15aT, and the wavelength division multiplexing unit 8a is connected to the optical fiber 51R and the optical switch unit 15aR. Alternatively, it can be configured such that a wavelength division multiplexing device 6, which is a single device equipped with the wavelength separation unit 7a and the wavelength division multiplexing unit 8a, is located outside the connection node device 1b, the wavelength separation unit 7a of the wavelength division multiplexing device 6 is connected to the optical fiber 51T and the optical switch unit 15aT, and the wavelength division multiplexing unit 8a of the wavelength division multiplexing device 6 is connected to the optical fiber 51R and the optical switch unit 15aR.

[0137] The optical switch unit 15aT is connected to the optical fiber 51T, the edge function unit 11b, and the optical fibers 52T-1 to 52T-n included in the optical transmission paths 52-1 to 52-n. The optical switch unit 15aT connects the wavelength path 61T-B of the fundamental wavelength among the wavelength paths obtained by wavelength splitting by the wavelength splitting unit 7a to the optical receiving unit 33 of the edge function unit 11b via the IF unit 31. In addition, the optical switch unit 15aT receives a switching indication signal and performs a switching process to connect any wavelength path included in the optical fiber 51T, excluding the wavelength path 61T-B of the fundamental wavelength, to any wavelength path included in the optical fibers 52T-1 to 52T-n.

[0138] The optical switch unit 15aR connects to the wavelength division multiplexing unit 8a, the edge function unit 11b, and the optical fibers 52R-1 to 52R-n included in the optical transmission paths 52-1 to 52-n. The optical switch unit 15aR connects the wavelength path 61R-B of the fundamental wavelength in the wavelength path included in the optical fiber 51R connected via the wavelength division multiplexing unit 8a to the optical transmission unit 35 of the edge function unit 11b via the IF unit 31. The optical switch unit 15aR receives a switching instruction signal and performs a switching process to connect any wavelength path in the optical fiber 51R other than the fundamental wavelength wavelength path 61R-B to any wavelength path included in the optical fibers 52R-1 to 52R-n.

[0139] The edge function unit 11b includes a control unit 12b and a connection information processing unit 13a. The connection information processing unit 13a includes an IF unit 31, a digital signal processing unit 32a, an optical receiver 33, an optical transmitter 35, and a connection information generation unit 38a. In addition to the structure of the digital signal processing unit 32 in the first and second embodiments, the digital signal processing unit 32a also has the following structure: When the received data signal output by the optical receiver 34 contains optical input information, the digital signal processing unit 32a reads out and acquires the optical input information from the received data signal. The digital signal processing unit 32a outputs the acquired optical input information to the connection information generation unit 38a.

[0140] The connection information generation unit 38a calculates the transmission path information of the optical transmission path 51 based on the received data signal output by the digital signal processing unit 32a of the connection information processing unit 13a. The connection information generation unit 38a generates connection information including the calculated transmission path information of the optical transmission path 51, the BER of the optical transmission path 51 output by the digital signal processing unit 32a, and the optical input information. The connection information generation unit 38a outputs the generated connection information and the connection request data output by the digital signal processing unit 32a to the control unit 12b.

[0141] The control unit 12b pre-stores an address path mapping table in its internal storage area. This address path mapping table is obtained by associating the address information of the optical transmission and receiving units 21aX-1 to 21aX-m and 21aY-1 to 21aY-n of each optical communication device 2aX and 2bY-1 to 2bY-n connected to the connection node device 1b with identification information for determining the optical transmission paths 51 and 52-1 to 52-n connected to the optical transmission and receiving units 21aX-1 to 21aX-m and 21aY-1 to 21aY-n corresponding to each address information. Alternatively, the control unit 12b may not pre-store the pre-acquired address path mapping table in its internal storage area, but may instead obtain the address path mapping table from an external device as needed.

[0142] The control unit 12b transmits the connection request data and connection information output by the connection information generation unit 38a to the operating device 4b via the connection line 3. The control unit 12b outputs the transmission mode information received from the operating device 4b to the digital signal processing unit 32a. The control unit 12b outputs a switching indication signal to the output port switching unit 14a.

[0143] The operating device 4b includes a path detection unit 41 and a transmission path design unit 42b. Regarding structures other than those shown below, the transmission path design unit 42b has the same structure as the transmission path design unit 42 of the second embodiment. Similar to the transmission path design unit 42 of the second embodiment, the transmission path design unit 42b selects configuration information through a predetermined selection process based on calculated transmission path characteristics, information indicating available resources of optical transmission paths 52-1 to 52-n corresponding to the connection destination address information included in the connection request data, and the desired bit rate information of the connection request data acquired by the digital signal processing unit 32a and the specification information of the optical transmitting and receiving units 21aX-1 to 21aX-m. However, the configuration information selected by the transmission path design unit 42b includes, in addition to the output optical power, modulation method, baud rate, bit rate, FEC (Forward Error Correction) type, and permitted signal band selected by the transmission path design unit 42 of the second embodiment, information on the center wavelength, and may also include information on the number of WDM wavelengths.

[0144] The wavelength division multiplexing (WDM) separation unit 6aX includes a WDM unit 8aX and a wavelength separation unit 7aX. The WDM unit 8aX combines and performs WDM multiplexing on optical signals of different wavelengths output from the IF units 22X-1 to 22X-m of the optical transceiver units 21aX-1 to 21aX-m, and then sends the WDM-multiplexed optical signals to the optical fiber 51T. The wavelength separation unit 7aX divides the WDM-multiplexed optical signals transmitted through the optical fiber 51R according to wavelength. The wavelength separation unit 7aX outputs each wavelength-separated optical signal to the IF units 22X-1 to 22X-m corresponding to their respective wavelengths. However, when multiple optical transceiver units 21aX-1 to 21aX-m are connected based on a basic mode, the wavelength separation unit 7aX outputs optical signals to all optical transceiver units 21aX-1 to 21aX-m connected based on the basic mode.

[0145] (Processing performed by the optical transmission system of the third embodiment)

[0146] Figure 10 This is a flowchart illustrating the processing flow performed by the optical transmission system 102. For example... Figure 9As shown, the optical switch 15aT of the output port switching unit 14a of the connection node device 1b connects the wavelength path 61T-B of the fundamental wavelength of the optical fiber 51T to the optical receiver 33 via the IF unit 31 of the connection node device 1b. The optical switch 15aR connects the wavelength path 61R-B of the fundamental wavelength of the optical fiber 51R to the optical modulator 37 via the IF unit 31 of the connection node device 1b.

[0147] The following is an example of a connection process where the optical transmitter / receiver unit 21aX-1 of the optical communication device 2aX is set as the connection point, and the optical transmitter / receiver unit 21aY-i of the optical communication device 2bY-i is set as the connection destination. The control unit 20aX of the optical transmitter / receiver unit 21aX-1 generates a connection request indication signal containing the address information of the optical transmitter / receiver unit 21aY-i and the desired bit rate in order to connect to the optical transmitter / receiver unit 21aY-i of the optical communication device 2bY-i. The control unit 20aX outputs the generated connection request indication signal to the control unit 71aX-1 of the optical transmitter / receiver unit 21aX-1. After receiving the connection request signal output by the control unit 20aX, the control unit 71aX-1, upon receiving a timing signal output by the transmission control unit 29X, begins processing at the timing indicated by the received timing signal (step Sb1).

[0148] The control unit 71aX-1 sets the address information of the optical transceiver 21aY-i contained in the acquired connection request signal as the connection destination address. The control unit 71aX-1 sets the address information of the optical transceiver 21aX-1 stored in its internal storage area as the connection party address information. The control unit 71aX-1 generates connection request data containing the connection destination address information, the connection party address information, the desired bit rate contained in the connection request indication signal, and the specification information of the optical transceiver 21aX-1 stored in its internal storage area.

[0149] The control unit 71aX-1 outputs an output optical power specification signal, representing the basic output optical power predetermined in the basic mode, to the wavelength-variable light source 25aX-1. The control unit 71aX-1 also outputs a wavelength specification signal, representing the basic wavelength predetermined in the basic mode, to the wavelength-variable light source 25aX-1. The control unit 71aX-1 outputs a modulation mode specification signal, representing the modulation mode predetermined in the basic mode, to the optical modulator 26X-1. The optical modulator 26X-1 begins optical modulation according to the basic modulation mode specified by the modulation mode specification signal.

[0150] The wavelength-variable light source 25aX-1 generates continuous light with a basic output optical power specified by the output optical power specification signal and a basic wavelength specified by the wavelength specification signal. The wavelength-variable light source 25aX-1 outputs the generated continuous light to the optical modulator 26X-1. The control unit 71aX-1 outputs the generated connection request data and the collected optical input information to the digital signal processing unit 23aX-1. The digital signal processing unit 23aX-1 acquires the connection request data and optical input information output by the control unit 71aX-1, and generates a transmission data signal by including the acquired connection request data in the idle area of ​​the transmission frame overhead and the optical input information in the communication channel of the transmission frame. The digital signal processing unit 23aX-1 outputs the generated electrical signal transmission data signal to the optical modulator 26X-1.

[0151] The optical modulator 26X-1 modulates the continuous light output from the wavelength-variable light source 25aX-1 based on the transmit data signal output from the digital signal processing unit 23aX-1. The optical modulator 26X-1 outputs the optical signal of the fundamental wavelength generated by optical modulation to the wavelength division multiplexing unit 8aX of the wavelength division multiplexing separation unit 6aX via the IF unit 22X-1. The wavelength division multiplexing unit 8aX combines the optical signal of the fundamental wavelength output from the IF unit 22X-1 with optical signals of other wavelengths and performs wavelength division multiplexing, then sends the wavelength-division multiplexed optical signal to the optical fiber 51T. The wavelength path 61T-B of the fundamental wavelength of the optical fiber 51T transmits the optical signal of the fundamental wavelength to the wavelength separation unit 7a of the connection node device 1b (step Sb2).

[0152] Wavelength separation unit 7a divides the optical signal transmitted by optical fiber 51T according to wavelength and outputs the resulting optical signals to optical switch unit 15aT. Optical switch unit 15aT receives the optical signal of the fundamental wavelength transmitted by wavelength path 61T-B of the fundamental wavelength of optical fiber 51T and outputs the received optical signal to optical receiver 34 of optical receiver unit 33 via IF unit 31. Optical receiver 34 acquires the optical signal output by optical switch unit 15aT. Optical receiver 34 converts the acquired optical signal into an electrical signal and sets it as a received data signal. Optical receiver 34 outputs the received data signal to digital signal processing unit 32a.

[0153] The digital signal processing unit 32a acquires the received data signal output by the optical receiver 34. The digital signal processing unit 32a reads and acquires connection request data contained in the overhead region of the acquired received data signal. The digital signal processing unit 32a reads and acquires the optical input information of the communication channel contained in the received data signal. The digital signal processing unit 32a acquires the BER of the optical transmission path 51 from the acquired received data signal. The digital signal processing unit 32a outputs the acquired connection request data, optical input information, and BER of the optical transmission path 51 to the connection information generation unit 38a.

[0154] The connection information generation unit 38a acquires the connection request data, optical input information, and BER of the optical transmission path 51 output by the digital signal processing unit 32a. When acquiring the connection request data, optical input information, and BER of the optical transmission path 51, the connection information generation unit 38a calculates and obtains the transmission path information of the optical transmission path 51 through predetermined calculations based on the received data signal acquired and output by the digital signal processing unit 32a. The connection information generation unit 38a generates connection information including the calculated transmission path information of the optical transmission path 51, the acquired optical input information, and the acquired BER of the optical transmission path 51. The connection information generation unit 38a outputs the acquired connection request data and the generated connection information to the control unit 12b (step Sb3).

[0155] The control unit 12b acquires the connection request data and connection information output by the connection information generation unit 38a. The control unit 12b then transmits the acquired connection request data and connection information to the operating device 4b via the connection line 3 (step Sb4).

[0156] The path detection unit 41 of the operating device 4b receives connection request data sent by the control unit 12b. The path detection unit 41 refers to a path information table stored in its internal storage area or a path information table obtained as needed, and detects identification information corresponding to the connection destination address information contained in the received connection request data, which in this case is the address information of the optical transmission receiver 21aY-i, used to determine the optical transmission path 52-i. The path detection unit 41 outputs the detected identification information for determining the optical transmission path 52-i to the transmission path design unit 42b (step Sb5).

[0157] The transmission path design unit 42b receives connection information and connection request data sent by the control unit 12b. The transmission path design unit 42b obtains the identification information output by the path detection unit 41 for determining the optical transmission path 52-i. The transmission path design unit 42b reads from its internal storage area and acquires the transmission path information of the optical transmission path 52-i corresponding to the acquired identification information for determining the optical transmission path 52-i, or acquires the transmission path information of the optical transmission path 52-i as needed. The transmission path design unit 42b calculates the transmission path characteristics based on the acquired transmission path information of the optical transmission path 52-i and the received connection information (step Sb6).

[0158] Based on the calculated transmission path characteristics, the desired bit rate information contained in the received connection request data, and the specification information of the optical transmitter / receiver unit 21aX-1, the transmission path design unit 42b selects configuration information through a prescribed selection process. The transmission mode is determined by the configuration information selected by the transmission path design unit 42b. The transmission path design unit 42b generates transmission mode information containing the selected configuration information and the connection address information contained in the connection request data (step Sb7).

[0159] The transmission path design unit 42b refers to the connection line table stored in the internal storage area and sends the generated transmission mode information to the control unit 20Y-i of the optical communication device 2bY-i through the connection line 3-i connected to the optical communication device 2bY-i, which has the connection destination address information contained in the connection request data, via the connection line 3-i connected to the optical communication device 2bY-i, which has the connection destination address information contained in the connection request data (step Sb8-1).

[0160] The control unit 20Y-i of the optical communication device 2bY-i receives the transmission mode information sent by the transmission path design unit 42b and outputs the received transmission mode information to the control unit 71aY-i of the optical transmit / receive unit 21aY-i. The control unit 71aY-i acquires the transmission mode information output by the control unit 20Y-i. The control unit 71aY-i outputs an output optical power specification signal, representing the output optical power shown in the acquired transmission mode information, to the wavelength-variable light source 25aY-i, and outputs a wavelength specification signal, representing the center wavelength specified in the acquired transmission mode information, to the wavelength-variable light source 25aY-i. Thus, the wavelength-variable light source 25aY-i generates and outputs continuous light of the wavelength specified by the wavelength specification signal, i.e., continuous light with the output optical power and center wavelength shown in the transmission mode information, at the output optical power specified by the output optical power specification signal. The wavelength-variable light source 25aY-i outputs the generated continuous light to the optical modulator 26Y-i.

[0161] The control unit 71aY-i outputs a modulation scheme specification signal, indicating the modulation scheme specified in the acquired transmission mode information, to the optical modulator 26Y-i. As a result, the optical modulator 26Y-i performs optical modulation using the modulation scheme specified by the modulation scheme specification signal received from the control unit 71aY-i, i.e., the modulation scheme shown in the transmission mode information. The control unit 71aY-i outputs the transmission mode information to the digital signal processing unit 23aY-i. The digital signal processing unit 23aY-i acquires the transmission mode information output by the control unit 71aY-i, and stores the modulation scheme, baud rate, bit rate, FEC type, permitted signal bandwidth, etc., shown in the acquired transmission mode information as setting parameters in its internal storage area. When generating a transmission data signal, it generates the transmission data signal based on the setting parameters stored in the internal storage area and outputs it to the optical modulator 26Y-i (step Sb9-1). Alternatively, the control unit 71aY-i may store the modulation scheme, baud rate, bit rate, FEC type, permitted signal frequency band, etc., shown in the transmission mode information as setting parameters in its internal storage area beforehand. In this case, the control unit 71aY-i outputs the setting parameters to the digital signal processing unit 23aY-i when the digital signal processing unit 23aY-i generates the transmission data signal.

[0162] The transmission path design unit 42b of the operating device 4b sends the transmission mode information representing the determined transmission mode and the identification information for determining the optical transmission path 52-i detected by the path detection unit 41 to the connection node device 1b via the connection line 3 (step Sb8-2).

[0163] The control unit 12b of the connection node device 1b receives transmission mode information and identification information for determining the optical transmission path 52-i sent by the transmission path design unit 42b. The control unit 12b outputs an output optical power specification signal to the single-wavelength light source 36 to specify the basic output optical power of the basic mode, and outputs a modulation scheme specification signal to the optical modulator 37 to specify the basic modulation scheme of the basic mode. The control unit 12b outputs the received transmission mode information to the digital signal processing unit 32a. The digital signal processing unit 32a acquires the transmission mode information output by the control unit 12b. The digital signal processing unit 32a generates a transmission data signal by including the acquired transmission mode information in the idle area of ​​the overhead of the transmission frame. The digital signal processing unit 32a outputs the generated electrical signal transmission data signal to the optical modulator 37. Based on the transmission data signal output by the digital signal processing unit 32a, the optical modulator 37 performs optical modulation on the continuous light of the basic wavelength output by the single-wavelength light source 36 according to the predetermined basic mode modulation scheme.

[0164] Optical modulator 37 outputs the optical signal generated by optical modulation to IF unit 31. IF unit 31 acquires the optical signal of the fundamental wavelength output by optical modulator 37. IF unit 31 outputs the acquired optical signal to optical switch unit 15aR. Optical switch unit 15aR outputs the optical signal of the fundamental wavelength from IF unit 31 to wavelength division multiplexing unit 8a. Wavelength division multiplexing unit 8a combines and performs wavelength division multiplexing on the multiple wavelength optical signals, including the optical signal of the fundamental wavelength, output by optical switch unit 15aR, and sends the wavelength division multiplexed optical signal to optical fiber 51R. The wavelength path 61R-B of the fundamental wavelength of optical fiber 51R transmits the optical signal sent by optical switch unit 15aR to wavelength separation unit 7aX of optical communication device 2aX (step Sb9-2).

[0165] The wavelength separation unit 7aX divides the optical signal transmitted through the optical fiber 51R into wavelengths. The wavelength separation unit 7aX outputs each wavelength-separated optical signal to the IF units 22X-1 to 22X-m corresponding to its respective wavelength. Furthermore, in the case of a fundamental wavelength optical signal, the wavelength separation unit 7aX outputs the fundamental wavelength optical signal via the IF units 22X-1 to 22X-m to the optical receiving units 27X-1 to 27X-m of all optical transmitting and receiving units 21aX-1 to 21aX-m connected to the edge functional unit 11b of the connection node device 1b. The IF unit 22X-1 of the optical transmitting and receiving unit 21aX-1 acquires the fundamental wavelength optical signal output by the wavelength separation unit 7aX. The IF unit 22X-1 outputs the acquired fundamental wavelength optical signal to the optical receiver 28X-1. The optical receiver 28X-1 receives the optical signal output by the IF unit 22X-1, converts the received optical signal into an electrical signal, and sets it as a receive data signal containing transmission mode information. The optical receiver 28X-1 outputs a received data signal containing transmission mode information to the digital signal processing unit 23aX-1. The digital signal processing unit 23aX-1 acquires the received data signal containing transmission mode information output by the optical receiver 28X-1.

[0166] The digital signal processing unit 23aX-1 reads transmission mode information from the overhead region of the acquired received data signal. The digital signal processing unit 23aX-1 outputs the read transmission mode information to the control unit 71aX-1. The control unit 71aX-1 acquires the transmission mode information output by the digital signal processing unit 23aX-1. If the address information contained in the acquired transmission mode information is not the address information attached to the optical transceiver unit 21aX-1 stored in its internal storage region, the control unit 71aX-1 discards the read transmission mode information. Conversely, if the address information contained in the acquired transmission mode information matches the address information attached to the optical transceiver unit 21aX-1, the control unit 71aX-1 outputs an output optical power specification signal, representing the output optical power shown in the acquired transmission mode information, to the wavelength-variable light source 25aX-1. The digital signal processing unit 23aX-1 outputs a wavelength specification signal, representing the center wavelength specified in the read transmission mode information, to the wavelength-variable light source 25aX-1. Therefore, the wavelength-variable light source 25aX-1 generates and outputs continuous light of the wavelength specified by the wavelength specification signal, i.e., continuous light with the output optical power and center wavelength shown in the transmission mode information, at the output optical power specified by the output optical power specification signal. The wavelength-variable light source 25aX-1 outputs the generated continuous light to the optical modulator 26X-1.

[0167] The control unit 71aX-1 outputs a modulation scheme specification signal, indicating the modulation scheme specified in the acquired transmission mode information, to the optical modulator 26X-1. The optical modulator 26X-1 performs optical modulation according to the modulation scheme specified by the modulation scheme specification signal received from the control unit 71aX-1. As a result, the optical modulator 26X-1 stops optical modulation based on the basic mode and begins optical modulation based on the modulation scheme specified in the transmission mode information. The control unit 71aX-1 outputs the transmission mode information to the digital signal processing unit 23aX-1. The digital signal processing unit 23aX-1 acquires the transmission mode information output by the control unit 71aX-1 and stores the modulation scheme, baud rate, bit rate, FEC type, permitted signal band, etc., shown in the acquired transmission mode information as setting parameters in its internal storage area. When generating a transmission data signal, the digital signal processing unit 23aX-1 generates the transmission data signal based on the setting parameters stored in its internal storage area and outputs it to the optical modulator 26X-1 (step Sb10). Alternatively, the control unit 71aX-1 may store the modulation scheme, baud rate, bit rate, FEC type, permitted signal frequency band, etc., shown in the transmission mode information as setting parameters in its internal storage area beforehand. In this case, the control unit 71aX-1 outputs the setting parameters to the digital signal processing unit 23aX-1 when the digital signal processing unit 23aX-1 generates the transmission data signal.

[0168] The control unit 12b of the connection node device 1b, based on the connection address information included in the received transmission mode information (here, the address information additional to the optical transmitter / receiver unit 21aX-1), detects identification information for determining the optical transmission path 51 from an address path mapping table stored in its internal storage area or from an address path mapping table obtained on demand. Based on the detected identification information for determining the optical transmission path 51, the received identification information for determining the optical transmission path 52-i, and the center wavelength specified in the transmission mode information, the control unit 12b generates a switching indication signal for connecting the wavelength path of the optical transmission path 51 (with the center wavelength specified in the transmission mode information) to the wavelength path of the optical transmission path 52-i (with the center wavelength specified in the transmission mode information). The control unit 12b outputs the generated switching indication signal to the output port switching unit 14a.

[0169] More specifically, such as Figure 11 As shown, the control unit 12b outputs a switching indication signal to the optical switch unit 15aT of the output port switching unit 14a, for setting the connection destination of the wavelength path 61T-1 of the optical fiber 51T, which is the center wavelength specified in the transmission mode information, to the wavelength path 62T-i of the optical fiber 52T-i, which is the center wavelength specified in the transmission mode information. The control unit 12b outputs a switching indication signal to the optical switch unit 15aR, for setting the connection destination of the wavelength path 61R-1 of the optical fiber 51R, which is the center wavelength specified in the transmission mode information, to the wavelength path 62R-i of the optical fiber 52R-i, which is the center wavelength specified in the transmission mode information.

[0170] When the optical switch unit 15aT receives a switching indication signal from the control unit 12b, it connects the wavelength path 61T-1 of optical fiber 51T with the wavelength path 62T-i of optical fiber 52T-i. When the optical switch unit 15aR receives a switching indication signal from the control unit 12b, it connects the wavelength path 61R-1 of optical fiber 51R with the wavelength path 62R-i of optical fiber 52R-i (step Sb11). Thus, the optical transmit / receive units 21aX-1 and 21aY-i are connected via wavelength paths 61T-1 and 62T-i, and wavelength paths 61R-1 and 62R-i.

[0171] Subsequently, for example, at the timing indicated by the timing signal received from the transmission control unit 29X, the optical transmitter / receiver unit 21aX-m sends connection request data, which sets the optical communication device 2bY-j to connect destination address information, to the connection node device 1b via the wavelength path 61T-B of the basic wavelength. In this case, as... Figure 12As shown, optical transmitter / receiver units 21aX-m and 21aY-j are connected via wavelength path 61T-2 in optical transmission path 51 and wavelength path 62T-j in optical transmission path 52, and wavelength path 61R-2 in optical transmission path 51 and wavelength path 62R-j in optical transmission path 52. Here, j is any integer from 1 to n, and is an integer different from i.

[0172] Furthermore, the processing order of steps Sb8-1 and Sb8-2 can be performed in parallel, in the order of steps Sb8-1 and Sb8-2, or in the reverse order.

[0173] In the structure of the third embodiment described above, the optical transmission and reception units 21aX-1 to 21aX-m of the optical communication device 2aX, corresponding to the connection address information of the connection request data, receive transmission mode information from the operation device 4b and send it to the optical transmission path 51 via the control unit 12b of the connection node device 1b. The optical transmission and reception units 21aX-1 to 21aX-m of the optical communication device 2aX transmit and receive optical signals via a wavelength path containing the center wavelength specified by the received transmission mode information within the optical transmission path 51. The optical transmission and reception units 21aY-i of the optical communication device 2bY-i transmit and receive optical signals via a wavelength path containing the center wavelength specified by the transmission mode information received from the operation device 4b within the optical transmission path 52-i. After the control unit 12b of the connection node device 1b sends transmission mode information to the optical communication device 2aX via the optical transmission path 51, the output port switching unit 14a of the connection node device 1b performs a switching process to connect the optical transmission and reception unit 21aX-s of the optical communication device 2aX and the optical transmission and reception unit 21aY-i of the optical communication device 2bY-i via a wavelength path specified by the transmission mode information included in the optical transmission path 51 and another wavelength path specified by the transmission mode information included in the optical transmission path 52-i. Therefore, when connecting the optical transmission and reception units 21aX-s and 21Y-i of the optical communication devices 2aX and 2bY-i via wavelength paths specified by the transmission mode included in multiple optical transmission paths 51 and 52-i, the connection can be performed without manual intervention using the optimal optical path of the transmission mode. This reduces the cost and time required for setting the optical path.

[0174] Furthermore, in the third embodiment described above, the connection information generation unit 38a of the connection node device 1b calculates the transmission path information of the optical transmission path 51 whenever the digital signal processing unit 32a outputs connection request data, BER, and optical input information to the connection information generation unit 38a. However, it can also be configured as follows: The transmission path information is not different for each wavelength path included in the optical transmission path 51; the transmission path information for each wavelength path included in the optical transmission path 51 is the same as the transmission path information of the optical transmission path 51. Therefore, the connection information generation unit 38a stores the calculated transmission path information of the optical transmission path 51 in its internal storage area beforehand. Alternatively, when the digital signal processing unit 32a subsequently receives connection request data and outputs the connection request data, BER, and optical input information to the connection information generation unit 38a, the connection information generation unit 38a does not recalculate the transmission path information of the optical transmission path 51, but instead reads the transmission path information of the optical transmission path 51 stored in its internal storage area and generates connection information.

[0175] In the third embodiment described above, optical input information is sent by optical transceiver units 21aX-1 to 21aX-m to connection node device 1b, and then sent by connection node device 1b to operation device 4b. The optical input information is information that can be pre-generated if information related to the optical transceiver units 21aX-1 to 21aX-m, such as transceiver type and number of transceivers, is known. Therefore, it is also possible that the transmission path design unit 42b of operation device 4b stores the optical input information it generates in advance in its internal storage area by establishing an association with address information. In this case, when calculating transmission path characteristics, the transmission path design unit 42b reads the optical input information stored in its internal storage area that corresponds to the connection address information included in the connection request data and performs the calculation of transmission path characteristics. Furthermore, since the digital signal processing units 23aX-1 to 23aX-m do not need to send optical input information, the connection information generated by the connection information generation unit 38a of connection node device 1b does not include optical input information.

[0176] In the optical transmission system 102 of the third embodiment described above, the optical transmitting and receiving units 21aX-1 to 21aX-m are connected to the connection node device 1b via an optical transmission path 51. Alternatively, the optical transmitting and receiving units 21aX-1 to 21aX-m may be connected to different optical transmission paths 51-1 and 51-2. Figure 13 The structure is similar to that of the optical transmission system 102a shown. Figure 13As shown, in the optical transmission system 102a, the optical communication device 2dX and the connection node device 1b are connected to two optical transmission paths 51-1 and 51-2. Furthermore, the wavelength division multiplexing separation units 6aX-1 and 6aX-2 of the optical communication device 2dX have the same structure as the wavelength division multiplexing separation unit 6aX. Additionally, the output port switching unit 14a of the connection node device 1b has two wavelength separation units 7a: one connected to the optical fiber 51T-1 and the optical switch unit 15aT included in the optical transmission path 51-1, and the other connected to the optical fiber 51T-2 and the optical switch unit 15aT included in the optical transmission path 51-2. In addition, the output port switching unit 14a has two wavelength division multiplexing units 8a, one connected to the optical fiber 51R-1 and the optical switch unit 15aR included in the optical transmission path 51-1, and the other connected to the optical fiber 51R-2 and the optical switch unit 15aR included in the optical transmission path 51-2.

[0177] In the optical transmission system 102a, the optical transmitting and receiving units 21aX-1 to 21aX-(mk) of the optical communication device 2dX are connected to the optical transmission path 51-1 via the wavelength division multiplexing separation unit 6aX-1, and the optical transmitting and receiving units 21aX-(m-k+1) to 21aX-m are connected to the optical transmission path 51-2 via the wavelength division multiplexing separation unit 6aX-2. Here, k is an integer between 1 and (m-1). In this case, optical transmitters and receivers 21aX-1 to 21aX-m send connection request data in the order indicated by the timing signal output by the transmission control unit 29X, and connect to any optical transmitter and receiver 21aY-1 to 21aY-n via wavelength paths 61-1-1, 61-2-1, ... of their respective connected optical transmission paths 51-1 or 51-2, 61-2-2, ...

[0178] In the third embodiment described above, if the transmission mode information includes the number of WDM wavelengths, the control units 71aX-1 to 71aX-m output the transmission mode information to the control unit 20aX. When the control unit 20aX obtains the transmission mode information output by any one of the control units 71aX-1 to 71aX-m, it refers to the number of WDM wavelengths included in the obtained transmission mode information. When the number of optical transmitters / receivers 21aX-1 to 21aX-m connected to the optical transmitters / receivers 21aY-1 to 21aY-n of the optical communication devices 2bY-1 to 2bY-n is the referenced number of WDM wavelengths, the control unit 20aX outputs a communication stop indication signal to the control units 71aX-1 to 71aX-m that are outputting transmission mode information, preventing the optical transmitters / receivers 21aX-1 to 21aX-m from communicating using optical signals. This prevents communication using optical signals exceeding the number of wavelengths multiplexed by the wavelength division multiplexing unit 8aX included in the wavelength division multiplexing separator 6aX. Furthermore, as the number of WDM wavelengths increases, the transmission distance becomes shorter. Therefore, it is conceivable that the optical signal transmitted by optical communication device 2dX may not reach optical communication devices 2bY-1 to 2bY-n, which are the connection destinations of optical transmission and reception units 21aX-1 to 21aX-m. In such a case of increasing WDM wavelengths, the number of optical transmission and reception units 21aX-1 to 21aX-m transmitting optical signals can be limited by the aforementioned communication stop indication signal, thereby preventing the transmitted optical signal from failing to reach optical communication devices 2bY-1 to 2bY-n.

[0179] In the first, second, and third embodiments described above, before the switching process is performed by the output port switching units 14 and 14a, the connection node devices 1, 1a, and 1b need to send the transmission mode information to the optical transmission path 51 in advance. In this case, during the processing in steps S5-2, Sa8-2, and Sb9-2, there is a time difference between the time from when the control units 12, 12a, and 12b output the transmission mode information to the digital signal processing units 32 and 32a until the optical switch units 15R and 15aR output the optical signal containing the transmission mode information. Therefore, by pre-measuring this time difference, the control units 12, 12a, and 12b need to process the output switching indication signal in steps S7, Sa10, and Sb11 after a pre-measured time has elapsed since the transmission mode information was output to the digital signal processing units 32 and 32a.

[0180] To make the timing of the start of steps S7, Sa10, and Sb11 more accurate, it can also be configured as follows. For example, when the control units 71X, 71aX-1, and 71aX-m of the optical transceiver units 21X, 21aX-1 to 21aX-m acquire the transmission mode information, they output information indicating that the reception of the transmission mode information has been completed to the digital signal processing units 23X, 23aX-1 to 23aX-m in basic mode. The digital signal processing units 23X, 23aX-1 to 23aX-m then send the information indicating that the reception of the transmission mode information has been completed to the connection node devices 1, 1a, and 1b. Alternatively, the control units 12, 12a, and 12b of the connection node devices 1, 1a, and 1b can output a switching indication signal to the output port switching units 14 and 14a upon receiving the information indicating that the reception of the transmission mode information transmitted by the optical transceiver units 21X, 21aX-1 to 21aX-m has been completed.

[0181] Alternatively, to make the timing of the start of steps S7, Sa10, and Sb11 more accurate, it can be done as follows. In the processing of steps S6-2, Sa9, and Sb10, when the optical modulators 26X, 26X-1 to 26X-m stop optical modulation based on the basic mode, the digital signal processing units 32 and 32a of the connecting node devices 1, 1a, and 1b detect the fact that the optical modulation based on the basic mode of the optical transmitters and receivers 21X, 21aX-1 to 21aX-m has stopped based on the presence or absence of the optical signal of the basic mode transmitted by the optical transmitters and receivers 21X, 21aX-1 to 21aX-m. Alternatively, the digital signal processing units 32 and 32a may notify the control units 12, 12a and 12b that the optical modulation based on the basic mode of the optical transmission and reception units 21X, 21aX-1 to 21aX-m, i.e., the optical output based on the basic mode, has stopped. Upon receiving the notification, the control units 12, 12a and 12b may output a switching indication signal to the output port switching units 14 and 14a.

[0182] (Other structural examples of the second and third embodiments)

[0183] Hereinafter, for ease of explanation, other structural examples of the second embodiment will be described, with the case where the light source used in generating the optical signal on the side sending the connection request data is a single-wavelength light source, and other structural examples of the third embodiment will be described, with the case where the light source used in generating the optical signal on the side sending the connection request data is a wavelength-variable light source. Furthermore, in the other structural examples of the second and third embodiments shown below, the same reference numerals are used for structures identical to those in the first to third embodiments.

[0184] (One of the structures for avoiding conflicts in connection request data)

[0185] Figure 14This is a block diagram showing the structure of an optical transmission system 101b as another structural example of the second embodiment. The optical transmission system 101b includes optical communication devices 2X-1 to 2X-m, a connection node device 1c, optical communication devices 2Y-1 to 2Y-n, an operation device 4, optical transmission paths 51-1 to 51-m connecting each of the optical communication devices 2X-1 to 2X-m to the connection node device 1c, optical transmission paths 52-1 to 52-n connecting each of the optical communication devices 2Y-1 to 2Y-n to the connection node device 1c, a connection line 3 connecting the operation device 4 to the connection node device 1c, and connection lines 3-1 to 3-n connecting the operation device 4 to each of the optical communication devices 2Y-1 to 2Y-n.

[0186] The connection node device 1c includes an edge function unit 11c and an output port switching unit 14. The output port switching unit 14 is connected to optical transmission paths 51-1 to 51-m, the connection information processing unit 13 of the edge function unit 11c, and optical communication devices 2Y-1 to 2Y-n. In the initial state, the output port switching unit 14 sets the connection destination of the optical transmission paths 51-1 to 51-m to the connection information processing unit 13 of the edge function unit 11c. When the output port switching unit 14 receives a switching instruction signal from the control unit 12c, it performs a switching process to connect any one of the optical transmission paths 51-1 to 51-m to any one of the optical transmission paths 52-1 to 52-n according to the received switching instruction signal.

[0187] The edge function unit 11c includes a connection information processing unit 13 and a control unit 12c. In addition to the structure of the control unit 12a in the second embodiment, the control unit 12c also has the following structure. In the optical transmission system 101b, for example, not as... Figure 8 Unlike the optical transmission system 102 shown, where a single optical communication device 2aX has multiple optical transceiver units 21aX-1 to 21aX-m, multiple optical communication devices 2X-1 to 2X-m each have one optical transceiver unit 21X-1 to 21X-m. Therefore, it is not possible to set different timings for transmitting connection request data using the transmission control unit 29X as in the optical transmission system 102.

[0188] The control unit 12c outputs timing information for sending connection request data and address information of the optical transceivers 21X-1 to 21X-m, including permission to send connection request data, to the digital signal processing unit 32 of the connection information processing unit 13, in a manner that allows setting different timings for sending connection data. Then, the timing information is transmitted to the optical transceivers 21X-1 to 21X-m through the same processing as when transmitting transmission mode information using the transmission data signal.

[0189] Each of the optical communication devices 2X-1 to 2X-m has the same structure as the optical communication device 2X in the first embodiment, but adds a processing structure for receiving optical signals containing the aforementioned timing information. The digital signal processing units 23X-1 to 23X-m in each of the optical communication devices 2X-1 to 2X-m read out timing information when the received data signal output by the optical receivers 28X-1 to 28X-m contains timing information. The digital signal processing units 23X-1 to 23X-m output the read timing information to their respective connected control units 71X-1 to 71X-m. When the address information included in the timing information output by the digital signal processing units 23X-1 to 23X-m is address information stored in their internal storage area that is attached to the optical transmitting / receiving units 21X-1 to 21X-m equipped with their own control units, the control units 71X-1 to 71X-m output connection request data according to the timing shown in the timing information. Therefore, the timing for transmitting connection request data by the optical transmitter / receiver units 21X-1 to 21X-m can be set to different timings.

[0190] (A Structure to Avoid Conflicts in Connection Request Data (Part Two))

[0191] Figure 15 This is a block diagram illustrating the structure of an optical transmission system 102b as another structural example of the third embodiment. The optical transmission system 102b includes optical communication devices 2eX-1 to 2eX-m, a connection node device 1d, an optical communication device 2fY, an operation device 4c, wavelength division multiplexing (WDM) separation devices 6X and 6Y, an optical transmission path 51, an optical transmission path 52, a connection line 3, and a connection line 3-1 connecting the operation device 4c to the optical communication device 2fY. The optical transmission path 51 connects the WDM separation device 6X to the connection node device 1d. The optical transmission path 52 connects the WDM separation device 6Y to the connection node device 1d. The connection line 3 connects the operation device 4c to the connection node device 1d. The connection line 3-1 connects the operation device 4c to the optical communication device 2fY.

[0192] Each of the optical communication devices 2eX-1 to 2eX-m includes an optical transmission and reception unit 21aX-1 to 21aX-m and a control unit 20X-1 to 20X-m. Optical communication device 2fY includes optical transmission and reception units 21aY-1 to 21aY-n and a control unit 20aY. Operation device 4c includes a path detection unit 41 and a transmission path design unit 42c.

[0193] Regarding structures other than those shown below, the transmission path design unit 42c has the same structure as the transmission path design unit 42b in the third embodiment. The transmission path design unit 42b, referring to the connection line table stored in its internal storage area, sends transmission mode information to the control units 20Y-1 to 20Y-n of the optical communication devices 2bY-1 to 2bY-n via connection lines 3-1 to 3-n corresponding to the connection destination address information included in the connection request data. In contrast, the transmission path design unit 42c appends the connection destination address information included in the connection request data to the generated transmission mode information and sends it to the control unit 20aY of the optical communication device 2fY via connection line 3-1. Therefore, the transmission path design unit 42c does not need to pre-store the connection line table in its internal storage area. The control unit 20aY, when referring to... Figure 7 As explained, when the transmission mode information with attached connection destination address information is received by the transmission path design unit 42c via the connection line 3-1, the transmission mode information is output to any one of the optical transmission and receiving units 21aY-1 to 21aY-n corresponding to the connection destination address information attached to the received transmission mode information.

[0194] Wavelength division multiplexing separation devices 6X and 6Y are used to... Figure 8 The wavelength division multiplexing (WDM) separation unit 6aX of the optical transmission system 102 shown is obtained as a single unit. The WDM separation unit 6X includes a wavelength separation unit 7aX and a wavelength division multiplexing unit 8aX, and the WDM separation unit 6Y includes a wavelength separation unit 7aY and a wavelength division multiplexing unit 8aY. Furthermore, with... Figure 8 Similarly, the optical communication device 2aX of the optical transmission system 102 shown can also have a structure in which a wavelength division multiplexing separation device 6Y is internally used as an internal functional unit, namely the wavelength division multiplexing separation unit 6aY.

[0195] The connection node device 1d includes an edge function unit 11d and an output port switching unit 14a. The output port switching unit 14a connects the wavelength path 61-B of the basic wavelength contained in the optical transmission path 51 to the connection information processing unit 13b of the edge function unit 11d, receives a switching instruction signal from the control unit 12d, and performs a switching process to connect any one of the wavelength paths 61-1 to 61-m contained in the optical transmission path 51 to any one of the wavelength paths 62-1 to 62-n contained in the optical transmission path 52.

[0196] The edge function unit 11d includes a connection information processing unit 13b and a control unit 12d. In addition to the structures of the connection information processing unit 13a and the control unit 12d in the third embodiment, the connection information processing unit 13b and the control unit 12d also have the following structures. In the optical transmission system 102b, with... Figure 14Similarly, in the optical transmission system 101b shown, each of the multiple optical communication devices 2eX-1 to 2eX-m has an optical transmitting and receiving unit 21aX-1 to 21aX-m. Therefore, it is not possible to... Figure 8 The timing for sending connection request data using the transmission control unit 29X is set to a different time, as shown in the optical transmission system 102.

[0197] The connection information processing unit 13b and the control unit 12d are configured to set the wavelengths of the basic wavelengths allocated to the light transmitting and receiving units 21aX-1 to 21aX-m to be different wavelengths in order to avoid conflicts in the wavelength path 61-B of the basic wavelength. The connection information processing unit 13b, instead of the single-wavelength light source 36, is equipped with, for example, a... Figure 9 The wavelength-variable light source shown is a wavelength-variable light source with the same structure as the wavelength-variable light source 25aX-1. Hereinafter, when referring to the wavelength-variable light source included with the connected information processing unit 13b, reference numeral "36a" will be added, and it will be referred to as wavelength-variable light source 36a. The digital signal processing unit 32a is connected to the wavelength-variable light source 36a and outputs a wavelength-specified signal to the wavelength-variable light source 36a.

[0198] The control unit 12d assigns different basic wavelengths to each of the optical transmitters and receivers 21aX-1 to 21aX-m. Therefore, the control unit 12d pre-selects the basic wavelengths assigned to each of the optical transmitters and receivers 21aX-1 to 21aX-m, and pre-stores the selected basic wavelengths in an internal storage area in association with the address information of each corresponding optical transmitter and receiver 21aX-1 to 21aX-m. The control unit 12d outputs the address information of each of the optical transmitters and receivers 21aX-1 to 21aX-m stored in the internal storage area, along with the basic wavelength specification information, to the digital signal processing unit 32a connected to the information processing unit 13b. Then, the basic wavelength specification information is transmitted to the optical transmitter and receiver units 21aX-1 to 21aX-m through the same process as in the case where the transmission mode information is transmitted by transmitting data signals through the wavelength path 61-B of the optical transmission path 51 before the change of the basic wavelength.

[0199] Each of the optical transmitting and receiving units 21aX-1 to 21aX-m has the same structure as the optical transmitting and receiving units 21aX-1 to 21aX-m in the third embodiment, but adds a processing structure for receiving optical signals containing the aforementioned basic wavelength specification information. The digital signal processing units 23aX-1 to 23aX-m in each of the optical transmitting and receiving units 21aX-1 to 21aX-m read out the basic wavelength specification information when the received data signal output from the photodetectors 28X-1 to 28X-m contains the basic wavelength specification information. The digital signal processing units 23aX-1 to 23aX-m output the read-out basic wavelength specification information to their respective connected control units 71aX-1 to 71aX-m. Control units 71aX-1 to 71aX-m acquire the basic wavelength specification information output by digital signal processing units 23aX-1 to 23aX-m, and read out the basic wavelength corresponding to their own address information contained in the acquired basic wavelength specification information, i.e., the address information stored in their internal storage area. Each control unit of control units 71aX-1 to 71aX-m outputs a wavelength specification signal for specifying the read basic wavelength to its corresponding wavelength-variable light source 25aX-1 to 25aX-m.

[0200] Therefore, each of the optical transmitting and receiving units 21aX-1 to 21aX-m generates an optical signal based on a different fundamental wavelength. For example, when transmitting transmission mode information, the control unit 12d reads the fundamental wavelength corresponding to the connection address information contained in the transmission mode information from its internal storage area. The control unit 12d generates a wavelength specification signal based on the information indicating the read fundamental wavelength. The control unit 12d outputs the generated wavelength specification signal to the wavelength-variable light source 36a. The wavelength-variable light source 36a generates and outputs continuous light of the fundamental wavelength specified by the wavelength specification signal. This changes the fundamental wavelength of the continuous light generated by the wavelength-variable light source 36a. The control unit 12d outputs the transmission mode information to the digital signal processing unit 32a. The digital signal processing unit 32a acquires the transmission mode information output by the control unit 12d and generates a transmission data signal containing the acquired transmission mode information. The digital signal processing unit 32a outputs the generated transmission data signal to the optical modulator 37. The optical modulator 37 modulates the continuous light of the modified basic wavelength output by the wavelength-variable light source 36a based on the transmitted data signal and generates an optical signal.

[0201] Therefore, the optical transmitter / receiver units 21aX-1 to 21aX-m and the connection node device 1d are connected using different fundamental wavelengths, which avoids conflicts in connection request data. However, in this case, when the optical transmitter / receiver units 21aX-1 to 21aX-m transmit connection request data using the fundamental wavelengths assigned to each optical transmitter / receiver unit, a conflict in the connection request data occurs in the optical receiver 34 of the connection node device 1b. To avoid this conflict, the connection node device 1d needs to terminate the wavelength paths of the different fundamental wavelengths individually. For example, suppose that the maximum number of fundamental wavelengths assigned by the connection node device 1d is predetermined. The optical receiver unit 33 of the connection information processing unit 13b of the connection node device 1d has a plurality of optical receivers 34 with a number consistent with the maximum number of fundamental wavelengths, and the optical switch unit 15aT of the output port switching unit 14a connects the output of the wavelength separation unit 7a to the plurality of optical receivers 34 in such a way that each optical receiver 34 is connected to a different fundamental wavelength. In this way, the control unit 12d of the connection node device 1d can distinguish and obtain the connection request data sent by the optical transmission and reception units 21aX-1 to 21aX-m respectively. Alternatively, instead of having multiple optical receivers 34, the optical receiver 33 may have multiple connection information processing units 13b of the same number as the maximum number of basic wavelengths.

[0202] Furthermore, the aforementioned structures for avoiding connection request data conflicts (one) and (two) are structures that transmit timing information or basic wavelength setting information, such as initial setting information for avoiding connection request data conflicts, from the control units 12c and 12d of the connection node devices 1c and 1d to the light transmission and reception units 21X-1 to 21X-m and 21aX-1 to 21aX-m. Alternatively, the method of transmitting this initial setting information for avoiding connection request data conflicts from the connection node devices 1c and 1d can be applied to, for example... Figure 8 The optical transmission system 102 shown is used in combination with a method that sets the timing of transmitting connection request data using the transmission control unit 29X to a different timing. By combining these methods, conflicts in connection request data can be avoided more reliably. Furthermore, in Figure 8In the optical transmission system 102 shown, it can also be configured such that the control unit 12b of the connection node device 1b sends initial setting information containing information indicating the timing of transmission of connection request data to the transmission control unit 29X of the optical communication device 2aX in advance. In response, the transmission control unit 29X sends information indicating that the reception of the initial setting information has been completed to the control unit 12b, etc. After sharing the timing of mutual transmission and reception of connection request data, the transmission control unit 29X outputs a timing signal to each optical transmission and reception unit 21aX-1 to 21aX-m based on the information indicating the timing of transmission of connection request data contained in the initial setting information.

[0203] against Figure 15 The control unit 12d of the optical transmission system 102b shown includes Figure 14 The structure of the control unit 12c of the optical transmission system 101b shown, which transmits timing information, can also be configured such that the control unit 12d simultaneously uses a method of changing the basic wavelength and a method of transmitting timing signals, or uses either method.

[0204] Alternatively, as a method to avoid conflicts in connection request data, the following approach can be applied: If, after sending connection request data, each of the optical transmitter / receiver units 21X-1 to 21X-m and 21aX-1 to 21aX-m does not receive a response from the connection node devices 1c and 1d within a predetermined period of time—for example, if it does not receive transmission mode information destined for itself—then, within a predetermined period of time or a randomly determined period of time, the optical transmitter / receiver units 21X-1 to 21X-m and 21aX-1 to 21aX-m cease optical output in basic mode. This reduces the probability of connection request data conflicts.

[0205] (The connection node device has a structure that includes a wavelength conversion section)

[0206] Figure 16 This is a block diagram illustrating the structure of an optical transmission system 101c based on another structural example of the second embodiment. The optical transmission system 101c includes a connection node device 1e, an optical communication device 2X, multiple optical communication devices 2bY-1 to 2bY-n, an operation device 4d, a wavelength division multiplexing / demultiplexing device 6Y, an optical transmission path 51, an optical transmission path 52, connection lines 3, and connection lines 3-1 to 3-n. The optical transmission path 51 connects the optical communication device 2X to the connection node device 1e. The optical transmission path 52 connects the wavelength division multiplexing / demultiplexing device 6Y to the connection node device 1e. The connection line 3 connects the operation device 4d to the connection node device 1e. The connection lines 3-1 to 3-n connect the operation device 4d to each of the optical communication devices 2bY-1 to 2bY-n.

[0207] The connection node device 1e includes an edge function unit 11e and an output port switching unit 14. The edge function unit 11e includes a control unit 12e, a connection information processing unit 13, and a wavelength conversion unit 16. Regarding structures other than those shown below, the control unit 12e has the same structure as the structure unit 12a in the second embodiment. That is, the control unit 12e transmits information about the connection node device 1e having a wavelength conversion unit 16 and information indicating the wavelength range that can be converted by the wavelength conversion unit 16 (hereinafter collectively referred to as "wavelength conversion unit information"), connection information output by the connection information processing unit 13, and connection request data to the operation device 4d via the connection line 3. The control unit 12e outputs information about the center wavelength from the transmission mode information sent by the transmission path design unit 42d of the operation device 4d to the wavelength conversion unit 16.

[0208] The operating device 4d includes a path detection unit 41 and a transmission path design unit 42d. Regarding structures other than those shown below, the transmission path design unit 42d has the same structure as the transmission path design unit 42 in the second embodiment. The transmission path design unit 42 pre-stores transmission path information for each of the optical transmission paths 52-1 to 52-n in its internal storage area, or acquires the transmission path information for each of the optical transmission paths 52-1 to 52-n as needed. Similarly, the transmission path design unit 42d pre-stores transmission path information for optical transmission path 52 in its internal storage area, or acquires the transmission path information for optical transmission path 52 as needed. Based on calculated transmission path characteristics, information detected by the path detection unit 41 indicating idle resources of the optical transmission path 52 corresponding to the connection destination address information, desired bit rate information included in the connection request data, specification information of the optical transmit / receive unit 21X, and wavelength conversion unit information, the transmission path design unit 42d selects configuration information through a predetermined selection process. The transmission path design unit 42d generates transmission mode information containing the selected configuration information.

[0209] In the optical transmission system 101c, by having the structure described above, the following processing is performed. (Refer to...) Figure 6 The flowchart shown illustrates this process. First, proceed with... Figure 6 The processes shown are steps Sa1 and Sa2. In step Sa1, the control unit 20X of the optical communication device 2X generates a connection request indication signal using address information of the optical transmission / reception unit 21aY-i, which is included in the optical communication device 2bY-i, as the address information of the connection destination. The optical communication device 2aY-i is connected to the connection line 3-i. In step Sa3, the control unit 12e transmits not only the connection information and connection request data but also wavelength conversion unit information to the operation device 4d via the connection line 3.

[0210] In step Sa4, the path detection unit 41 of the operating device 4d detects identification information for determining the optical transmission path 52 based on the connection request data, which corresponds to the address information of the optical transmit / receive unit 21aY-i. In step Sa5, the transmission path design unit 42d obtains the identification information for determining the optical transmission path 52 output by the path detection unit 41. The transmission path design unit 42d reads from its internal storage area and obtains the transmission path information of the optical transmission path 52 corresponding to the obtained identification information for determining the optical transmission path 52, or obtains the transmission path information of the optical transmission path 52 as needed. The transmission path design unit 42d calculates the transmission path characteristics based on the obtained transmission path information of the optical transmission path 52 and the received connection information.

[0211] In step Sa6, the transmission path design unit 42d selects configuration information based on the calculated transmission path characteristics, the received wavelength conversion unit information, the desired bit rate information contained in the received connection request data, and the specification information of the optical transmitter / receiver unit 21X, through a prescribed selection process. The transmission path design unit 42d generates transmission mode information that includes the selected configuration information and the connection party address information contained in the connection request data.

[0212] In step Sa7-1, the transmission path design unit 42d, referring to the connection line table stored in its internal storage area, sends the generated transmission mode information to the control unit 20Y-i of the optical communication device 2bY-i via connection line 3-i corresponding to the connection destination address information contained in the connection request data. Afterwards, instead of step Sa8-1, the control unit 20Y-i and the optical transmission and reception unit 21aY-i perform communication... Figure 10 The process shown in step Sb9-1 is the same.

[0213] Therefore, in the optical transmitter / receiver unit 21aY-i, the wavelength-variable light source 25aY-i generates continuous light with the output optical power and the center wavelength shown in the transmission mode information, and outputs it to the optical modulator 26Y-i. The optical modulator 26Y-i performs optical modulation using the modulation method shown in the transmission mode information. The digital signal processing unit 23aY-i generates a transmission data signal based on setting parameters such as the modulation method, baud rate, bit rate, FEC type, and permitted signal bandwidth shown in the transmission mode information, and outputs it to the optical modulator 26Y-i.

[0214] In step Sa7-2, the transmission path design unit 42d sends the generated transmission mode information and the identification information for determining the optical transmission path 52 detected by the path detection unit 41 to the connection node device 1e via the connection line 3. Afterwards, steps Sa8-2 and Sa9 are performed by the control unit 12e, the connection information processing unit 13, the output port switching unit 14 of the connection node device 1e, and the optical transmission and reception unit 21X of the optical communication device 2X.

[0215] In step Sa10, the control unit 12e of the connection node device 1e outputs information representing the center wavelength contained in the transmission mode information received through the connection line 3 to the wavelength conversion unit 16. Based on the connection address information contained in the transmission mode information (here, the address information of the optical transmitter / receiver unit 21X), the control unit 12e detects identification information for determining the optical transmission path 51 from an address path mapping table stored in its internal storage area or from an address path mapping table obtained on demand. Based on the detected identification information for determining the optical transmission path 51 and the identification information for determining the optical transmission path 52 received from the transmission path design unit 42d of the operation device 4d, the control unit 12e generates a switching indication signal. The control unit 12e outputs the generated switching indication signal to the output port switching unit 14. Thus, the output port switching unit 14 connects the optical transmission path 51 to the wavelength conversion unit 16.

[0216] When the optical transmitter / receiver unit 21X of the optical communication device 2X transmits an optical signal to the connection node device 1e through the optical transmission path 51, the output port switching unit 14 of the connection node device 1e outputs the optical signal received through the optical transmission path 51 to the wavelength conversion unit 16. The wavelength conversion unit 16 acquires the optical signal output by the output port switching unit 14. The wavelength conversion unit 16 converts the wavelength of the acquired optical signal to the center wavelength provided by the control unit 12e and sends it to the optical transmission path 52. Here, the center wavelength provided by the control unit 12e refers to the center wavelength shown in the transmission mode information. Therefore, the wavelength of the optical signal sent by the wavelength conversion unit 16 to the optical transmission path 52 is the same as the wavelength of the optical signal transmitted by the optical transmitter / receiver unit 21aY-1 of the optical communication device 2bY-i. Therefore, when the wavelength path of the center wavelength shown in the transmission mode information is set to wavelength path 62-i, the wavelength conversion unit 16 and the optical transmitter / receiver unit 21aY-i will be connected through wavelength path 62-i.

[0217] The optical signal sent from the wavelength conversion unit 16 to the optical transmission path 52 is transmitted through the wavelength path 62-i to the wavelength separation unit 7aY of the wavelength division multiplexing separation device 6Y. The wavelength separation unit 7aY divides the wavelength-division multiplexed optical signal transmitted from the optical transmission path 52 into wavelengths. The wavelength separation unit 7aY outputs each wavelength-division optical signal to the optical transmission and reception units 21aY-1 to 21aY-n corresponding to each wavelength. Thus, the optical signal transmitted by the optical transmission and reception unit 21X of the optical communication device 2X reaches the optical transmission and reception unit 21aY-i of the optical communication device 2bY-i.

[0218] In the aforementioned optical transmission system 101c, the edge functional section 11e of the connection node device 1e includes a wavelength conversion section 16. This allows the optical transmitter / receiver unit 21X of the optical communication device 2X to convert to any wavelength, even if it has a single-wavelength light source 25X, which cannot change its wavelength. Therefore, by using the connection node device 1e, a lower-cost optical transmitter / receiver unit 21aX-1 compared to one with a wavelength-variable light source 25aX-1 can be used to switch wavelengths, and the optical transmitter / receiver unit 21aY-1 to 21aY-n can be connected via any of the wavelength paths 62-1 to 62-n included in the optical transmission path 52.

[0219] (Regarding this other structural example)

[0220] In addition to the structures shown in the optical transmission systems 101, 101a, 101b, 101c, 102, 102a, and 102b described above, the following structures are also possible. For example, it can also be configured such that... Figure 8 In the optical transmission system 102 shown, the optical communication device 2aX does not have a wavelength division multiplexing separation unit 6aX. For each optical transmission and receiving unit 21aX-1 to 21aX-m, one end of an optical transmission path (the reference numerals of the m optical transmission paths are set as 51-1 to 51-m) is connected, and the other end of the optical transmission path 51-1 to 51-m is connected to the output port switching unit 14a.

[0221] exist Figure 13 In the optical transmission system 102a shown, instead of the optical communication device 2bY-1 connected to the optical transmission path 52-1, it can also have Figure 15 The optical communication device 2fY and the wavelength division multiplexing demultiplexer 6Y connected to the optical communication device 2fY are shown. The wavelength division multiplexing demultiplexer 6Y is connected to the optical transmission path 52-1. Figure 13 In the optical transmission system 102a shown, it can also be configured to replace the optical communication device 2bY-1 connected to the optical transmission path 52-1, and have the following features: Figure 16The optical communication devices 2bY-1 to 2bY-n and the wavelength division multiplexing demultiplexing device 6Y connected to the optical communication devices 2bY-1 to 2bY-n are shown. The wavelength division multiplexing demultiplexing device 6Y is connected to the optical transmission path 52-1. Figure 13 In the optical transmission system 102a shown, it can also be configured to replace the optical communication devices 2bY-1 to 2bY-n, and have the following features: Figure 15 The optical communication device 2fY shown connects one optical transmitter / receiver unit 21aY-1 to 21aY-n to each of the optical transmission paths 52-1 to 52-n. Figure 13 In the optical transmission system 102a shown, it can also be configured to replace the optical communication device 2dX, and have two units. Figure 8 The optical communication device 2aX shown includes a wavelength division multiplexing separation unit 6aX that connects to one optical communication device 2aX via optical transmission path 51-1, and a wavelength division multiplexing separation unit 6aX that connects to the other optical communication device 2aX via optical transmission path 51-2.

[0222] exist Figure 14 In the optical transmission system 101b shown, it can also be configured to replace the optical communication devices 2X-1 to 2X-m, using an optical communication device comprising optical transmission and reception units 21X-1 to 21X-m, a control unit 20aX connected to each optical transmission and reception unit 21X-1 to 21X-m, and a transmission control unit 29X connected to each optical transmission and reception unit 21X-1 to 21X-m, to connect one optical transmission and reception unit 21X-1 to 21X-m to each optical transmission path 51-1 to 51-md. Figure 14 In the optical transmission system 101b shown, it can also be configured to replace the optical communication devices 2Y-1 to 2Y-n, and have the following features: Figure 7 The optical communication device 2cY shown connects one optical transmitter / receiver unit 21Y-1 to 21Y-n to each of the optical transmission paths 52-1 to 52-n.

[0223] exist Figure 16 In the optical transmission system 101c shown, it can also be configured to replace the optical communication device 2X and have the following features: Figure 14 The optical communication devices 2X-1 to 2X-m shown replace one optical transmission path 51 with multiple optical transmission paths 51-1 to 51-m connected to the output port switching unit 14, and each optical transmission path 51-1 to 51-m is connected to an optical transmitter / receiver unit 21X-1 to 21X-m. Figure 16In the optical transmission system 101c shown, it can also be configured to replace the optical communication device 2X and the optical transmission path 51, and include an optical communication device having optical transmission and reception units 21X-1 to 21X-m, a control unit 20aX connected to each optical transmission and reception unit of the optical transmission and reception units 21X-1 to 21X-m, and a transmission control unit 29X connected to each optical transmission and reception unit of the optical transmission and reception units 21X-1 to 21X-m, as well as optical transmission paths 51-1 to 51-m connected to each optical transmission and reception unit of the optical transmission and reception units 21X-1 to 21X-m and the output port switching unit 14.

[0224] exist Figure 8 In the optical transmission system 102 shown, it can also be configured such that, instead of the optical communication device 2aX having a wavelength division multiplexing separation unit 6aX internally, it is as follows: Figure 15 The optical transmission system 102b is installed externally as a wavelength division multiplexing separation device 6X. Similarly, in Figure 13 In the optical transmission system 102a shown, it can also be configured such that, instead of the optical communication device 2dX having wavelength division multiplexing separation units 6aX-1 and 6aX-1 internally, it is as follows: Figure 15 The optical transmission system 102b is installed externally as wavelength division multiplexing separation devices 6X-1 and 6X-2.

[0225] For example, in the third embodiment and other structural examples of the third embodiment, it can also be set to replace... Figure 9 The light transmitting and receiving units 21aX-1 to 21aX-m shown are equipped with wavelength-variable light sources 25aX-1 to 25a-m and are used in... Figure 2 The light transmitting and receiving unit shown has the same structure as the light transmitting and receiving unit 21X with a single wavelength light source 25X. For the structure described above with operating devices 4, 4a, 4b, 4c, and 4d, the following can also be applied: Figure 1 The optical transmission system 100 shown does not have the structure of operating devices 4, 4a, 4b, 4c, and 4d.

[0226] In the first to third embodiments and other structural examples of each embodiment described above, the control unit 12 of the first embodiment and the transmission path design units 42, 42a, 42b, 42c, and 42d of the second and third embodiments select configuration information for determining the transmission mode through a predetermined selection process based on the transmission path characteristics, desired bit rate information, and specification information of the optical transmission and reception units 21X, 21X-1 to 21X-m, 21aX, 21aX-1 to 21aX-m. Alternatively, the transmission mode can be determined as follows.

[0227] For example, several modes are selected, combining transmission path characteristics, desired bit rate information, and specification information of optical transceiver units 21X, 21X-1 to 21X-m, 21aX, 21aX-1 to 21aX-m. Configuration information for each selected mode is selected, and a transmission mode information table is pre-generated that associates the selected configuration information with the combination of transmission path characteristics, desired bit rate information, and specification information of optical transceiver units 21X, 21X-1 to 21X-m, 21aX, 21aX-1 to 21aX-m. This table is then pre-stored in the internal storage areas of the control unit 12 and the transmission path design units 42, 42a, 42b, 42c, and 42d. In such a structure, the control unit 12 and the transmission path design units 42, 42a, 42b, 42c, and 42d can replace the processing of the selection configuration information. Instead, they refer to the transmission mode information table stored in the internal storage area to read the combination of configuration information corresponding to the combination of transmission path characteristics, expected bit rate information, and specification information of optical transmitter and receiver units 21X, 21X-1 to 21X-m, 21aX, 21aX-1 to 21aX-m. They then generate transmission mode information that includes the combination of the read configuration information and the connection address information included in the connection request data.

[0228] Furthermore, a different number (hereinafter referred to as "transmission mode number") is attached to each record in the aforementioned transmission mode information table. This transmission mode information table with the attached transmission mode number is pre-stored not only in the storage areas inside the control unit 12 and the transmission path design units 42, 42a, 42b, 42c, and 42d, but also in the storage areas inside the control units 12b and 12d and the control units 71X, 71X-1 to 71X-m, 71aX, 71aX-1 to 71aX-m, 71Y, 71Y-1 to 71Y-n, 71aY, 71aY-1 to 71aY-n. The transmission mode information table is also pre-stored in the storage areas inside the control units 12b and 12d of the connection node devices 1b and 1d because the control units 12b and 12d need to generate a switching indication signal output to the output port switching unit 14a based on the center wavelength contained in the transmission mode information.

[0229] The control unit 12 and the transmission path design units 42, 42a, 42b, 42c, and 42d refer to the transmission mode information table stored in their internal storage areas to detect the transmission mode number corresponding to the combination of transmission path characteristics, desired bit rate information, and specification information of the optical transmitter / receiver units 21X, 21X-1 to 21X-m, 21aX, 21aX-1 to 21aX-m. The control unit 12 and the transmission path design units 42, 42a, 42b, 42c, and 42d generate transmission mode information that includes the detected transmission mode number and the connection address information included in the connection request data.

[0230] When control units 12b, 12d and control units 71X, 71X-1 to 71X-m, 71aX, 71aX-1 to 71aX-m, 71Y, 71Y-1 to 71Y-n, 71aY, 71aY-1 to 71aY-n obtain transmission mode information sent by control units 12 and transmission path design units 42, 42a, 42b, 42c, 42d, they refer to the transmission mode information table in the internal storage area to read the configuration information corresponding to the transmission mode number contained in the obtained transmission mode information. Through this process, control units 12b, 12d and control units 71X, 71X-1 to 71X-m, 71aX, 71aX-1 to 71aX-m, 71Y, 71Y-1 to 71Y-n, 71aY, 71aY-1 to 71aY-n can also be notified of the transmission mode determined by the transmission mode number.

[0231] Furthermore, in the second and third embodiments described above, as well as other structural examples of each embodiment, the transmission path design units 42, 42a, 42b, 42c, and 42d calculate the End-To-End, i.e., the transmission path characteristics from the connecting party to the connecting destination, based on the connection information received from the connection node devices 1a, 1b, 1c, 1d, and 1e and the transmission path information of the optical transmission paths 52 and 52-i corresponding to the connection destination address information contained in the connection request data. This can also be configured as follows.

[0232] The control units 12a, 12b, 12c, 12d, and 12e of the connection node devices 1a, 1b, 1c, 1d, and 1e calculate the transmission path characteristics based on the connection information of optical transmission paths 51, 51-1 to 51-m, and send the calculated transmission path characteristics to the operation devices 4, 4a, 4b, 4c, and 4d instead of the connection information. The transmission path design units 42, 42a, 42b, 42c, and 42d of the operation devices 4, 4a, 4b, 4c, and 4d calculate the transmission path characteristics of optical transmission paths 52, 52-1 to 52-n corresponding to the connection destination address information included in the connection request data, based on the transmission path information of optical transmission paths 52, 52-1 to 52-n stored in their internal storage areas, or the transmission path information of optical transmission paths 52, 52-1 to 52-n obtained as needed. Alternatively, the transmission path design units 42, 42a, 42b, 42c, and 42d may calculate the estimated end-to-end transmission path characteristics based on the transmission path characteristics received from the control units 12a, 12b, 12c, 12d, and 12e, and the transmission path characteristics calculated based on the transmission path information of optical transmission paths 52 and 52-i. Furthermore, the transmission path design units 42, 42a, 42b, 42c, and 42d may not calculate the transmission path characteristics of optical transmission paths 52 and 52-1 to 52-n based on the transmission path information of optical transmission paths 52 and 52-i, but may instead be configured as follows. The transmission path design units 42, 42a, 42b, 42c, and 42d pre-calculate the transmission path characteristics of optical transmission paths 52, 52-1 to 52-n based on the transmission path information of the optical transmission paths 52, 52-1 to 52-n, and pre-store the calculated transmission path characteristics of the optical transmission paths 52, 52-1 to 52-n in their internal storage areas. By pre-setting this structure, the transmission path design units 42, 42a, 42b, 42c, and 42d can replace the processing of calculating the transmission path characteristics of optical transmission paths 52, 52-1 to 52-n, and instead perform the processing of reading the transmission path characteristics of optical transmission paths 52, 52-1 to 52-n from their internal storage areas to obtain the transmission path characteristics of optical transmission paths 52, 52-1 to 52-n.

[0233] In the first to third embodiments and other structural examples of each embodiment described above, the output port switching unit 14 includes two optical switch units 15T and 15R, and the output port switching unit 14a includes two optical switch units 15aT and 15aR. Alternatively, the structure can be configured such that the output port switching units 14 and 14a each include one optical switch unit, and the port setting of this one optical switch unit is used to distinguish between the port used for transmitting and the port used for receiving.

[0234] The aforementioned output port switching unit 14a may use, for example, a WSS or a fiber optic patch panel. Alternatively, an AWG (Arrayed Waveguide Grating) may be used as the output port switching unit 14a. For example, for... Figure 15 The output port switching unit 14a of the optical transmission system 102b shown uses an AWG (Aperture Gauge), and it is predetermined that wavelength paths above 1530 nm and below 1540 nm will be output to the connection information processing unit 13b, and wavelength paths above 1540 nm and below 1560 nm will be output to the optical transmission path 52. The control unit 12d sends information indicating that the connection node device 1d has an AWG as the output port switching unit 14a, as well as information indicating the wavelength paths preset in the AWG, along with connection information, to the operation device 4c. The transmission path design unit 42c of the operation device 4c generates transmission mode information by adding the information received from the control unit 12d indicating the presence of an AWG and the information indicating the wavelength paths preset in the AWG. In this way, by applying an AWG to the output port switching unit 14a, the optical transmitting and receiving units 21aX-1 to 21aX-m can switch from a connection to the connection node device 1d to an optical transmission path 52 by changing the wavelengths of their respective wavelength-variable light sources 25aX-1 to 25aX-m according to the transmission mode information. Therefore, the control unit 12d does not need to output a switching indication signal to the output port switching unit 14a.

[0235] (Fourth Implementation)

[0236] Figure 17This is a block diagram showing the structure of the optical transmission system 103 in the fourth embodiment. In the fourth embodiment, the same reference numerals are used for structures that are the same as those in the first to third embodiments and other structural examples of each embodiment. The different structures will be described below. The optical transmission system 103 includes optical communication devices 2bX and 2bY, connection node devices 1fX and 1fY, an operation device 4e, an optical transmission path 51 connecting the optical transmission and reception unit 21aX of the optical communication device 2bX to the output port switching unit 14aX of the connection node device 1fX, an optical transmission path 53 connecting the optical transmission and reception unit 21aY of the optical communication device 2bY to the output port switching unit 14aY of the connection node device 1fY, an optical transmission path 52 connecting the output port switching unit 14aX of the connection node device 1fX to the output port switching unit 14aY of the connection node device 1fY, a connection line 3X connecting the connection node device 1fX to the operation device 4e, and a connection line 3Y connecting the connection node device 1fY to the operation device 4e. Here, optical transmission path 52 is, for example, an optical transmission path constituting a carrier network owned by a communication operator, and optical transmission paths 51 and 53 are, for example, dark optical fibers. Optical communication devices 2bX and 2bY are, for example, communication devices used by users.

[0237] The optical transmission and reception units 21aX and 21aY of the optical communication devices 2bX and 2bY are equipped with... Figure 8 The optical transmission and receiving unit 21aX-1 of the optical transmission system 102 shown has the same structure. Hereinafter, when indicating the functional parts of each of the optical transmission and receiving units 21aX and 21aY, the branch number "X-1" of the reference numerals of each functional part of the optical transmission and receiving unit 21aX-1 will be replaced with "X" and "Y" respectively.

[0238] The output port switching units 14aX and 14aY of the connecting node devices 1fX and 1fY are equipped with... Figure 8 The output port switching section 14a of the connection node device 1b of the optical transmission system 102 shown has the same structure. Hereinafter, when indicating the functional parts of each of the output port switching sections 14aX and 14aY, the reference numeral "a" of each functional part of the output port switching section 14a will be replaced with "aX" and "aY" respectively.

[0239] The information processing units 13aX and 13aY are equipped with... Figure 8 The connection information processing unit 13a of the connection node device 1b of the optical transmission system 102 shown has the same structure. Hereinafter, when indicating the functional units of each of the connection information processing units 13aX and 13aY, the branch number "a" of the reference numerals of each functional unit of the connection information processing unit 13a will be replaced with "aX" and "aY" respectively.

[0240] The control units 12fX and 12fY of the connecting node devices 1fX and 1fY, in addition to having Figure 8 In addition to the structure of the control unit 12b of the connection node device 1b in the optical transmission system 102 shown, the control unit 12b also has the following structure: Identification information for identifying each connection node device 1fX and 1fY is pre-attached to each connection node device. The control unit 12fX pre-stores the identification information for identifying connection node device 1fX in its internal storage area. When sending connection information and connection request data to the operation device 4e, the control unit 12fX adds the identification information for identifying connection node device 1fX stored in its internal storage area before sending it to the operation device 4e. Similarly, the control unit 12fY pre-stores the identification information for identifying connection node device 1fY in its internal storage area. When sending connection information and connection request data to the operation device 4e, the control unit 12fY adds the identification information for identifying connection node device 1fY stored in its internal storage area before sending it to the operation device 4e.

[0241] The operating device 4e includes a path detection unit 41 and a transmission path design unit 42e. The transmission path design unit 42e stores transmission path information of the optical transmission path 52 in its internal storage area in a manner that associates it with identification information used to determine the optical transmission path 52. Furthermore, the transmission path design unit 42e can either pre-calculate the transmission path information of the optical transmission path 52 based on the optical signal transmitted through the optical transmission path 52 and store it in its internal storage area, or it can retrieve it from an external device as needed at specific times, such as during network deployment. Additionally, the transmission path information of the optical transmission path 52 can also be pre-calculated using methods other than those specified in the calculations.

[0242] The transmission path design unit 42e pre-stores information indicating the available resources of the optical transmission path 52 in its internal storage area. Here, the information indicating available resources refers to, for example, information about wavelengths, wavelength ranges, or optical transmission paths not used in communication when determining the availability of resources. Furthermore, the information indicating available resources stored in the internal storage area of ​​the transmission path design unit 42e is configured to be updated by the transmission path design unit 42e whenever a communication path is established. The transmission path design unit 42e also pre-stores a connection line table in its internal storage area, which is obtained by associating identification information used to determine the connection node device 1fX with connection line 3X and information used to determine the connection node device 1fY with connection line 3Y.

[0243] The transmission path design unit 42e stores data in its internal storage area. Figure 18The connection status table 43 is shown. The record format of connection status table 43 includes items such as "Requester Address Information," "Connection Destination Address Information," "Connection Node Device," "Connection Destination Optical Transmission Path," and "Received Data." The connection provider address information contained in the connection request data is written into the "Requester Address Information" item. The connection destination address information contained in the connection request data is written into the "Connection Destination Address Information" item.

[0244] The "Connection Node Device" section includes the identification information received by the transmission path design unit 42e along with the connection request data, used to determine the connection node device 1fX and 1fY. The "Connection Destination Optical Transmission Path" section includes the identification information detected by the path detection unit 41, corresponding to the connection destination address information included in the connection request data, used to determine the optical transmission path 52. The "Received Data" section includes the connection information and connection request data received by the transmission path design unit 42e.

[0245] In order to connect the optical transmitter / receiver units 21aX and 21aY, the transmission path design unit 42e calculates the transmission path characteristics of the optical transmission path from optical transmission path 51 through optical transmission path 52 to optical transmission path 53, referring to the connection status table 43. Based on the calculated transmission path characteristics, the transmission path design unit 42e determines the transmission mode applied to the optical transmitters 24aX and 24aY.

[0246] (Processing of the optical transmission system in the fourth embodiment)

[0247] Next, refer to Figure 19 and Figure 20 The processing performed by the optical transmission system 103 of the fourth embodiment will be explained. Figure 19 This is a flowchart illustrating the processing flow performed by the optical transmission system 103 according to the fourth embodiment. In the initial state, the output port switching unit 14aX of the connection node device 1fX connects the wavelength path of the basic wavelength of the optical transmission path 51 to the connection information processing unit 13aX of the edge function unit 11fX of the connection node device 1fX. In the initial state, the output port switching unit 14aY of the connection node device 1fY connects the wavelength path of the basic wavelength of the optical transmission path 53 to the connection information processing unit 13aY of the edge function unit 11fY of the connection node device 1fY.

[0248] The following process will be explained: The optical transmitter / receiver unit 21aX of the optical communication device 2bX sets the optical transmitter / receiver unit 21aY of the optical communication device 2bY as the connection destination and performs the connection; the optical transmitter / receiver unit 21aY of the optical communication device 2bY sets the optical transmitter / receiver unit 21aX of the optical communication device 2bX as the connection destination and performs the connection.

[0249] The control unit 20X of the optical communication device 2bX generates a connection request indication signal containing address information and desired bit rate of the optical transceiver unit 21aY, for connection to the optical transceiver unit 21aY of the optical communication device 2bX. The control unit 20X outputs the generated connection request indication signal to the control unit 71aX of the optical transceiver unit 21aX. The control unit 71aX receives the connection request signal output by the control unit 20X and sets the address information of the optical transceiver unit 21aY contained in the received connection request signal as the connection destination address. The control unit 71aX sets the address information of the optical transceiver unit 21aX stored in its internal storage area as the connection party address information. The control unit 71aX generates connection request data containing connection destination address information, connection party address information, desired bit rate contained in the connection request indication signal, and specification information of the optical transceiver unit 21aX stored in its internal storage area. Then, the optical transceiver unit 21aX of the optical communication device 2bX performs connection with... Figure 10 The same process as step Sb2 (step Sc1-1) applies.

[0250] The control unit 20Y of the optical communication device 2bY generates a connection request indication signal containing address information and desired bit rate of the optical transceiver unit 21aX, for connection to the optical transceiver unit 21aX of the optical communication device 2bX. The control unit 20Y outputs the generated connection request indication signal to the control unit 71aY of the optical transceiver unit 21aX. The control unit 71aY receives the connection request signal output by the control unit 20Y and sets the address information of the optical transceiver unit 21aX contained in the received connection request signal as the connection destination address. The control unit 71aY sets the address information of the optical transceiver unit 21aX stored in its internal storage area as the connection party address information. The control unit 71aY generates connection request data containing connection destination address information, connection party address information, desired bit rate contained in the connection request indication signal, and specification information of the optical transceiver unit 21aX stored in its internal storage area. Then, the optical transceiver unit 21aY of the optical communication device 2bY performs connection with... Figure 10 The same process as step Sb2 (steps Sc1-2) is applied.

[0251] Step Sc2-1 involves the output port switching unit 14aX and the connection information processing unit 13aX of the connection node device 1fX. Figure 10 The same processing is performed as in step Sb3. Here, the transmission path information calculated by the connection information generation unit 38aX of the connection node device 1fX is the transmission path information of the optical transmission path 51, and the connection information generation unit 38aX generates the connection information of the optical transmission path 51. Step Sc2-2 is performed in the output port switching unit 14aY and the connection information processing unit 13aY of the connection node device 1fY. Figure 10 The process is the same as step Sb3. Here, the transmission path information calculated by the connection information generation unit 38aY of the connection node device 1fY is the transmission path information of the optical transmission path 53, and the connection information generation unit 38aY generates the connection information of the optical transmission path 53.

[0252] Control unit 12fX acquires the connection information and connection request data of optical transmission path 51 output by connection information generation unit 38aX. Control unit 12fX sends the acquired connection information of optical transmission path 51, the acquired connection request data, and the identification information for determining connection node device 1fX stored in its internal storage area to operation device 4e via connection line 3X (step Sc3-1). Control unit 12fY acquires the connection information and connection request data of optical transmission path 53 output by connection information generation unit 38aY. Control unit 12fY sends the acquired connection information of optical transmission path 53, the acquired connection request data, and the identification information for determining connection node device 1fY stored in its internal storage area to operation device 4e via connection line 3Y (step Sc3-2).

[0253] The operating device 4e performs the transmission mode determination process (step Sc4). Figure 20 This is a flowchart illustrating the processing flow of the subroutine for determining the transmission mode. The following describes the process after step Sc3-1, when the operating device 4e receives connection information, connection request data, and identification information for determining the connection node device 1fX from the control unit 12fX of the connection node device 1fX via the optical transmission path 51.

[0254] The path detection unit 41 of the operating device 4e receives connection request data and identification information for determining the connection node device 1fX sent by the control unit 12fX of the connection node device 1fX. The path detection unit 41 refers to a path information table stored in its internal storage area or a path information table obtained as needed to detect identification information for determining the optical transmission path 52 that corresponds to the connection destination address information (in this case, the address information of the optical transmitter / receiver unit 21aY) contained in the received connection request data. The path detection unit 41 outputs the detected identification information for determining the optical transmission path 52 and the received identification information for determining the connection node device 1fX to the transmission path design unit 42e.

[0255] The transmission path design unit 42e receives connection information, connection request data, and identification information for determining the connection node device 1fX from the control unit 12fX of the connection node device 1fX. The transmission path design unit 42e acquires the identification information for determining the optical transmission path 52 and the identification information for determining the connection node device 1fX output by the path detection unit 41. In this case, the combination of the connection information, connection request data, and identification information for determining the connection node device 1fX received by the transmission path design unit 42e from the control unit 12fX of the connection node device 1fX, and the combination of the identification information for determining the optical transmission path 52 and the identification information for determining the connection node device 1fX acquired by the transmission path design unit 42e as the output of the path detection unit 41, are consistent in that they are used to determine the identification information of the connection node device 1fX. Therefore, the transmission path design unit 42e considers these combinations to be in a corresponding relationship and performs the following processing based on the connection information of the optical transmission path 51, the connection request data, the identification information for determining the optical transmission path 52, and the identification information for determining the connection node device 1fX.

[0256] The transmission path design unit 42e generates a new record in the connection status table 43 stored in its internal storage area. The transmission path design unit 42e writes the connection party address information (in this case, the address information of the optical transceiver unit 21aX) contained in the received connection request data into the "Requester Address Information" field of the generated record. The transmission path design unit 42e also writes the connection destination address information (in this case, the address information of the optical transceiver unit 21aY) contained in the received connection request data into the "Connection Destination Address Information" field of the same record.

[0257] The transmission path design unit 42e writes the received identification information for determining the connection node device 1fX into the "Connection Node Device" field of the record. The transmission path design unit 42e writes the identification information obtained as the output of the path detection unit 41 for determining the optical transmission path 52 into the "Connection Destination Optical Transmission Path" field of the record. The transmission path design unit 42e writes the received connection information and connection request data of the optical transmission path 51 into the "Received Data" field of the record.

[0258] For example, in the case of Figure 19If the processing of step Sd1, performed as a result of step Sc3-1, completes before the processing of step Sd1, performed as a result of step Sc3-2, then at the point in time when the processing of step Sd1, performed as a result of step Sc3-1, is completed, no record related to the optical transmitting / receiving unit 21aY of the optical communication device 2bY will be generated in the connection status table 43 of the transmission path design unit 42e. On the other hand, if the processing of step Sd1, performed as a result of step Sc3-2, completes before the processing of step Sd1, performed as a result of step Sc3-1, then at the point in time when the processing of step Sd1, performed as a result of step Sc3-1, is completed, a record related to the optical transmitting / receiving unit 21aY of the optical communication device 2bY will be generated in the connection status table 43 of the transmission path design unit 42e.

[0259] To determine which of these states it is, the transmission path design unit 42e refers to the connection status table 43 to determine whether there is a record in which the address information of the optical transmitter / receiver unit 21aY has been written into the "requester address information" field of the newly generated record "connection destination address information", and increments the value of the processing count counter set in the internal storage area by "1". The initial value of the processing count counter is "0" (step Sd2).

[0260] The transmission path design unit 42e is configured such that the address information of the optical transmitter / receiver unit 21aY, which was determined to be missing in the "Connection Destination Address Information" field, is written into the "Requester Address Information" field (step Sd2, "No"). In this case, the processing of step Sd1, which was executed due to step Sc3-2, is not completed. Therefore, the transmission path design unit 42e waits for a certain period of time to generate a record related to the optical transmitter / receiver unit 21aY of the optical communication device 2bY in the connection status table 43 (step Sd3).

[0261] If the address information of the optical transmitter / receiver unit 21aY is written into the "requester address information" field of the "connection destination address information" field, the transmission path design unit 42e determines whether the value of the counter for the number of processing times stored in the internal storage area is "2" or more (step Sd4).

[0262] The reason for performing the determination process in step Sd4 is that the transmission mode determination process of step Sc4, which relates to the optical transmit / receive unit 21aX of the optical communication device 2bX and is performed after the process in step Sc3-1, and the transmission mode determination process of step Sc4, which relates to the optical transmit / receive unit 21aY of the optical communication device 2bY and is performed after the process in step Sc3-2, are not executed in parallel, thus stopping the transmission mode determination process of one of them. When the value of the processing count counter is "1", the determination process in step Sd2 is performed only once. At the time of this determination process, it means that a record has already been generated in the connection state table 43 through the processing of step Sd1, which was the previous transmission mode determination process. Therefore, in this case, the previous transmission mode determination process is prioritized, thus stopping the subsequent transmission mode determination process.

[0263] If the value of the counter for the number of processing operations stored in the internal storage area is not "2" or higher (step Sd4, "No"), the transmission path design unit 42e terminates the process. On the other hand, if the value of the counter for the number of processing operations stored in the internal storage area is "2" or higher (step Sd4, "Yes"), the transmission path design unit 42e performs the following determination process.

[0264] The transmission path design unit 42e determines whether the connection conditions are met for the two records of the connection object stored in the connection status table 43: the record in which the address information of the optical transceiver 21aX is written in the "Requester Address Information" field and the record in which the address information of the optical transceiver 21aY is written in the "Connection Destination Address Information" field. (Step Sd5) Here, the connection condition means, for example, that in the two records of the connection object stored in the connection status table 43, the address information written in the "Requester Address Information" field of one party is consistent with the address information written in the "Connection Destination Address Information" field of the other party, and the content of the "Connection Destination Optical Transmission Path" field is consistent.

[0265] Here, the address information of optical transceiver 21aY is written into the "Connection Destination Address Information" field of the record where the "Requester Address Information" field contains the address information of optical transceiver 21aX. Similarly, the address information of optical transceiver 21aX is written into the "Connection Destination Address Information" field of the record where the "Requester Address Information" field contains the address information of optical transceiver 21aY. Therefore, the first connection condition is satisfied: the address information written in one party's "Requester Address Information" field is consistent with the address information written in the other party's "Connection Destination Address Information" field. Identification information for determining the optical transmission path 52 is written into the "Connection Destination Optical Transmission Path" field of the record where the "Requester Address Information" field contains the address information of optical transceiver 21aX, and identification information for determining the optical transmission path 52 is written into the "Connection Destination Optical Transmission Path" field of the record where the "Requester Address Information" field contains the address information of optical transceiver 21aY. Therefore, the second connection condition is also satisfied: the content of the "Connection Destination Optical Transmission Path" field is consistent.

[0266] Therefore, the transmission path design unit 42e determines that the connection conditions are met (step Sd5, "Yes"). The transmission path design unit 42e reads the connection information of the optical transmission path 51 from the "Received Data" item in the record where the "Requester Address Information" is the address information of the optical transceiver unit 21aX. The transmission path design unit 42e reads the connection information of the optical transmission path 53 from the "Received Data" item in the record where the "Requester Address Information" is the address information of the optical transceiver unit 21aY.

[0267] The transmission path design unit 42e reads and obtains the transmission path information of the optical transmission path 52 from its internal storage area, or obtains the transmission path information of the optical transmission path 52 as needed. Based on the read connection information of the optical transmission path 51 and the connection information of the optical transmission path 53, and the obtained transmission path information of the optical transmission path 52, the transmission path design unit 42e calculates the transmission path characteristics using a transmission design tool such as the internally available GNPy (step Sd6).

[0268] The transmission path design unit 42e selects configuration information based on the calculated transmission path characteristics, the information on idle resources of the optical transmission path 52 corresponding to the connection destination address information detected by the path detection unit 41 stored in the internal storage area, the expected bit rate information and specification information of the optical transmission and reception units 21aX and 21aY written in the connection request data (the records of the address information of the optical transmission and reception unit 21aX and 21aY in the "Requester Address Information" field and the records of the address information of the optical transmission and reception unit 21aY in the "Requester Address Information" field), through a prescribed selection process. The transmission path design unit 42e generates transmission mode information (step Sd7) containing the selected configuration information and the connection address information contained in the connection request data, and returns to... Figure 19 The flowchart shown illustrates the processing.

[0269] On the other hand, if the transmission path design unit 42e determines that the connection conditions are not met (step Sd5, "No"), it notifies the outside that the connection cannot be established and terminates the process.

[0270] The transmission path design unit 42e, referring to the connection line table stored in its internal storage area, sends the generated transmission mode information and the identification information for determining the optical transmission path 52 detected by the path detection unit 41 to the control unit 12fX of the connection node device 1fX via the connection line 3X (step Sc5-1). The transmission path design unit 42e, referring to the connection line table stored in its internal storage area, sends the generated transmission mode information and the identification information for determining the optical transmission path 52 detected by the path detection unit 41 to the control unit 12fY of the connection node device 1fY via the connection line 3Y (step Sc5-2). Furthermore, the processing order of steps S5-1 and Sc5-2 can be parallel, sequential, or in reverse order.

[0271] Subsequently, in the connection node device 1fX, the edge function unit 11fX and the output port switching unit 14aX perform the following operations: Figure 10 The same process as step Sb9-2 (step Sc6-1) is performed in the optical transmission and reception unit 21aX of the optical communication device 2bX, and the same process as step Sb10 (step Sc7-1) is performed in the connection node device 1fY, in the edge function unit 11fY and the output port switching unit 14aY. Figure 10 The same process as step Sb9-2 (step Sc6-2) is performed in the optical transmission and reception unit 21aY of the optical communication device 2bY as in step Sb10 (step Sc7-2).

[0272] The control unit 12fX of the connection node device 1fX performs communication with... Figure 10 The same processing as step Sb11, namely the switching process of connecting the wavelength path of the optical transmission path 52 corresponding to the wavelength path of the optical transmission path 52 and the wavelength path of the center wavelength specified in the transmission mode information with the wavelength path of the optical transmission path 51 and the wavelength path of the center wavelength specified in the transmission mode information (step Sc8-1). The control unit 12fY of the connection node device 1fY performs the same processing as step Sb11. Figure 10 The same process as step Sb11, namely the switching process of connecting the wavelength path of the optical transmission path 52 corresponding to the received identification information for determining the optical transmission path 52 with the wavelength path of the center wavelength specified in the transmission mode information of the optical transmission path 53, and the wavelength path of the center wavelength specified in the transmission mode information (step Sc8-2). Thus, the optical transmitter / receiver unit 21aX and the optical transmitter / receiver unit 21aY are connected through the wavelength paths of the optical transmission paths 51, 52, and 53, respectively, and the wavelength paths of the center wavelength specified in the transmission mode information.

[0273] Furthermore, the timing for performing steps Sc8-1 and Sc8-2 can be applied to any of the following methods: a method of performing steps Sc8-1 and Sc8-2 after the time has elapsed as described above; a method of performing steps Sc8-1 and Sc8-2 at the time of receiving information indicating that the transmission mode information has been received; and a method of performing steps Sc8-1 and Sc8-2 upon receiving a notification that the optical output based on the basic mode has stopped.

[0274] In the optical transmission system 103, the structure of the transmission mode information table described above can also be applied, and the structure of the control units 12fX and 12fY that notify the optical transmitting and receiving units 21aX and 21aY and the connection node devices 1fX and 1fY of the transmission mode determined by the transmission mode number can also be applied.

[0275] In the structure of the fourth embodiment described above, the operating device 4e is connected to the connection node device 1fX and the connection node device 1fY. It reads and obtains the transmission path information of the optical transmission path 52, which serves as the second optical transmission path, pre-stored in the internal storage area, or obtains the transmission path information of the optical transmission path 52 as needed. Based on the obtained transmission path information of the optical transmission path 52, the connection information processing unit 13aX of the connection node device 1fX obtains the connection information of the optical transmission path 51, which serves as the first optical transmission path, from the optical signal transmitted by the optical transmission and reception unit 21aX of the optical communication device 2bX, which serves as the first optical communication device. The optical transmission and reception unit 21aX of optical communication device 2bY transmits connection request data in the form of an optical signal; the connection information processing unit 13aY of optical communication device 2bY obtains connection information of optical transmission path 53, which is a third optical transmission path, from the optical signal transmitted by the optical transmission and reception unit 21aY of optical communication device 2bY (which is a second optical communication device); and the connection request data transmitted by the optical transmission and reception unit 21aY of optical communication device 2bY in the form of an optical signal. The transmission mode information indicating the determined transmission mode is then sent to the control unit 12fX of connection node device 1fX and the control unit 12fY of connection node device 1fY. The output port switching unit 14aX of connection node device 1fX performs switching processing after the control unit 12fX sends the transmission mode information to the optical transmission and reception unit 21aX via optical transmission path 51; the output port switching unit 14aY of connection node device 1fY performs switching processing after the control unit 12fY sends the transmission mode information to the optical transmission and reception unit 21aY of optical communication device 2bY via optical transmission path 53. Therefore, the optical transmitter / receiver unit 21aX of the optical communication device 2bX and the optical transmitter / receiver unit 21aY of the optical communication device 2bY are connected via optical transmission paths 51, 52, and 53. The optical transmitter / receiver unit 21aX of the optical communication device 2bX receives transmission mode information from the control unit 12fX of the connection node device 1fX and sends it to the optical transmission path 51 from the operation device 4e, and transmits and receives optical signals through the optical transmission path 51 according to the transmission mode indicated by the received transmission mode information. The optical transmitter / receiver unit 21aY of the optical communication device 2bY receives transmission mode information from the control unit 12fY of the connection node device 1fY and sends it to the optical transmission path 53 from the operation device 4e, and transmits and receives optical signals through the optical transmission path 53 according to the transmission mode indicated by the received transmission mode information. Therefore, when the optical transmitting and receiving units 21aX and 21aY of the optical communication devices 2bX and 2bY are connected to each other via multiple optical transmission paths 51, 52 and 53, the connection can be made through the optical path of the optimal transmission mode without manual operation.Therefore, it can reduce the cost and time required to set the path of light.

[0276] Furthermore, in the fourth embodiment described above... Figure 20 In step Sd8 shown, in addition to notifying the outside of the inability to connect, the optical transmission and reception unit 21aX of the optical communication device 2bX and the optical transmission and reception unit 21aY of the optical communication device 2bY can also be notified of the inability to connect via the wavelength path of the basic wavelength.

[0277] (One of the other structural examples of the fourth embodiment)

[0278] The optical transmission system 103 of the fourth embodiment described above includes two connection node devices 1fX and 1fY. However, it may also be configured to have more connection node devices of the same structure (hereinafter, these are referred to as connection node devices 1f-1 to 1f-k, and the connection lines connecting each connection node device 1f-1 to 1f-k are referred to as connection lines 3-1 to 3-k. Here, k is an integer greater than or equal to 3). Functional units with the same structure as optical transmission and reception units 21aX and 21aY, which are configured as multiple optical transmission and reception units, are connected to each connection node device 1f-1 to 1f-k in the manner shown in the second and third embodiments and other structural examples of each embodiment. In this case, the transmission path design unit 42e, which is set as the operation device 4e, receives, for example, connection information of the optical transmission path connected to the connection node device 1f-1 sent by the control unit 12f-1 of the connection node device 1f-1, connection request data requesting connection to the optical transmission and reception unit of the optical communication device connected to any one of the connection node devices 1f-2 to 1f-k, and identification information for determining the connection node device 1fX-1.

[0279] Transmission Path Design Department 42e onwards Figure 19 In step Sc4, the transmission mode determination process, if no record related to the optical transmission / reception unit of the optical communication device serving as the connection destination is generated in the connection status table 43, such as... Figure 20The process in step Sd3 waits for a certain period of time. It is also conceivable that even after waiting for a certain period, no record related to the optical transmitter / receiver unit of the optical communication device serving as the connection destination is generated in the connection status table 43, and the connection node devices 1f-2 to 1f-k fail to transmit connection information, etc. To prevent such a situation, the transmission path design unit 42e of the operation device 4e may send trigger signals to all connection node devices 1f-2 to 1f-k (excluding connection node device 1f-1) via the connection lines connected to each connection node device 1f-2 to 1f-k, causing the connection node devices 1f-2 to 1f-k to retransmit the connection information, etc.

[0280] (Another structural example of the fourth embodiment (part two))

[0281] For example, suppose that the optical transmission and reception unit 21aX of the optical communication device 2bX in the fourth embodiment sends connection request data to set the optical transmission and reception unit 21aY of the optical communication device 2bY as the connection destination, thereby the control unit 12fY of the connection node device 1fY receives a trigger signal for retransmitting the connection information sent by the transmission path design unit 42e of the operation device 4e. The control unit 12fY sends a transmission path information acquisition instruction signal to all optical communication devices connected to the connection node device 1fY in the basic mode via basic mode communication for acquiring transmission path information. Here, suppose, for example Figure 17 As shown, only one optical communication device 2bY is connected to the connection node device 1fY, and the following description is provided.

[0282] The optical receiver 27Y of the optical transmitter-receiver unit 21aY of the optical communication device 2bY receives the optical signal, which includes a transmission path information acquisition indication signal, transmitted from the optical transmission path 53. It converts the received optical signal into an electrical signal, a received data signal, and outputs it to the digital signal processing unit 23aY. The digital signal processing unit 23aY acquires the received data signal output by the optical receiver 28Y, reads the transmission path information acquisition indication signal from the acquired received data signal, and outputs the read transmission path information acquisition indication signal to the control unit 71aY. When the control unit 71aY acquires the transmission path information acquisition indication signal output by the digital signal processing unit 23aY, it acquires information related to the optical transmission path 53 from the received data signal acquired by the digital signal processing unit 23aY. Here, the information related to the optical transmission path 53 can be either the transmission path information of the optical transmission path 53 calculated by the control unit 71aY based on the received data signal acquired by the digital signal processing unit 23aY and through a predetermined calculation, or it can be information needed to calculate the transmission path information of the optical transmission path 53.

[0283] The control unit 71aY outputs the acquired information related to the optical transmission path 53 to the digital signal processing unit 23aY for transmission to the connection node device 1fY. Furthermore, if the control unit 71aY has connection request data that has been reserved, it re-outputs the connection request data along with the calculated transmission path information of the optical transmission path 53 to the digital signal processing unit 23aY.

[0284] In this case, the connection information generation unit 38aY of the connection node device 1fY replaces the processing of calculating the transmission path information of the optical transmission path 53, and can obtain the connection information of the optical transmission path 53 based on the information related to the optical transmission path 53 sent by the optical communication device 2bY. More specifically, when the information related to the optical transmission path 53 is the transmission path information of the optical transmission path 53, the connection information generation unit 38aY can obtain the transmission path information of the optical transmission path 53 without performing the processing of calculating the transmission path information of the optical transmission path 53. Furthermore, when the information related to the optical transmission path 53 is the information required to calculate the transmission path information of the optical transmission path 53, the transmission path information of the optical transmission path 53 can be calculated based on this information through a predetermined operation, thereby obtaining the transmission path information of the optical transmission path 53.

[0285] Furthermore, if the connection destination address information included in the connection request data retransmitted by the control unit 71aY of the optical transceiver unit 21aY is the address information of the optical transceiver unit 21aX of the optical communication device 2bX, the optical transceiver unit 21aX and the optical transceiver unit 21aY can be connected via a trigger signal. Therefore, the transmission path design unit 42e of the operation device 4e can... Figure 20 In step Sd3, instead of waiting for a certain period of time, a trigger signal is sent, thereby enabling the active acquisition of the transmission path information and connection request data of the optical transmission path 53 from the optical transmission and receiving unit 21aY of the optical communication device 2bY, so as to connect the optical transmission and receiving unit 21aX with the optical transmission and receiving unit 21aY.

[0286] Furthermore, the transmission path information of the optical transmission path 53 calculated by the control unit 71aY of the optical transmission and reception unit 21aY, and the transmission path information of the optical transmission path 53 calculated by the connection information generation unit 38aY of the connection node device 1fY based on the information required for calculating the transmission path information of the optical transmission path 53 and through a predetermined calculation, is the transmission path information of the optical transmission path 53 from the connection node device 1fY to the optical communication device 2bY. Therefore, in the fourth embodiment, the transmission path information of the optical transmission path 53 calculated by the connection information generation unit 38aY of the connection node device 1fY is the transmission path information of the optical transmission path 53 from the optical communication device 2bY to the connection node device 1fY. The characteristics of the optical fiber 53T and optical fiber 53R in the optical transmission path 53 can generally be considered the same. Therefore, the same transmission path characteristics can be calculated using any transmission path information of the optical transmission path 53, and the same transmission mode can be determined.

[0287] Furthermore, the control unit 12fY of the connection node device 1fY can also send a transmission path information acquisition indication signal to the optical transmission and reception unit of the newly connected optical communication device. Additionally, the transmission path information acquisition indication signal and the information related to the optical transmission path 53 acquired by the control unit 71aY of the connection node device 1fY can be sent through the idle area of ​​the overhead of the transmission frame, or through the communication channel of the transmission frame or the payload area of ​​the transmission frame. Furthermore, in the first to fourth embodiments and other structural examples of each embodiment, when acquiring the transmission path information of optical transmission paths 51, 51-1 to 51-m, the method for acquiring the transmission path information of optical transmission path 53 described above can also be applied, i.e., the method of calculating the transmission path information of optical fibers 51R, 51R-1 to 51R-m instead of calculating the transmission path information of the optical fibers 51T, 51T-1 to 51T-m provided in optical transmission paths 51, 51-1 to 51-m.

[0288] In the fourth embodiment, instead of optical communication devices 2bX and 2bY, optical communication device 2X having an optical transmission and reception unit 21X with a single wavelength light source 25X and optical transmission and reception unit 21Y having a single wavelength light source 25Y can be connected to connection node devices 1fX and 1fY respectively.

[0289] Furthermore, in the first to fourth embodiments described above, the idle area of ​​the overhead region of the transmission frame is used to send connection request data and transmission mode information. Alternatively, the connection request data and transmission mode information can be sent via the communication channel of the transmission frame, or via the payload region of the transmission frame.

[0290] In the first to fourth embodiments described above, connection information containing BER is generated, but it can also be configured to generate connection information without BER.

[0291] In the third and fourth embodiments described above, a communication channel is used to transmit optical input information. Alternatively, the optical input information can be transmitted via the GCC (General Communication Channel) in the frame header.

[0292] In the first and second embodiments described above, there is only one optical transmitter / receiver unit 21X for sending connection request data. Therefore, the control unit 12 and the transmission path design unit 42 of the operation device 4 can also omit the connection address information contained in the connection request data when generating transmission mode information. In the fourth embodiment, one optical transmitter / receiver unit 21aX and 21aY are connected to each connection node device 1fX and 1fY respectively. Therefore, in this case, the operation device 4e can also omit the connection address information contained in the connection request data when generating transmission mode information. In the third embodiment, when m=1, the connection address information contained in the connection request data can also be omitted when generating transmission mode information. When the transmission mode information does not include the connection address information, the control units 71X, 71Y, 71aX, 71Y, 71X-1, 71Y-1, 71aX-1, 71Y-1, 71aX-1, 71aY-1 of the optical transmitting and receiving units 21X, 21Y, 21aX, 21aY, 21X-1, 21Y-1, and 71aY-1 of the optical transmitting and receiving units 21X, 21Y, 21aX, 21aY, 21X-1, 21Y-1, and 71aY-1 acquire the digital signal processing units 23X, 23Y, 23aX, 23aY, 23X-1, and 23Y-1. When outputting transmission mode information, 23aX-1 and 23aY-1 do not need to determine whether the acquired transmission mode information contains address information stored in the internal storage area for the optical transmitting and receiving units 21X, 21Y, 21aX, 21aY, 21X-1, 21Y-1, 21aX-1, and 21aY-1 equipped with the control unit. Instead, the acquired transmission mode information can be set to the transmission mode information corresponding to the connection request data generated by the unit itself.

[0293] In the first to fourth embodiments and various other structural examples described above, the basic output optical power may not be predetermined in the basic mode. In this case, when transmitting optical signals in the basic mode, single-wavelength light sources 25X, 25Y, 25X-1 to 25X-m, 25Y-1 to 25Y-m and wavelength-variable light sources 25aX, 25aY, 25aX-1 to 25aX-m, 25aY-1 to 25aY-m will generate optical signals with initial output optical power.

[0294] The transmission path design unit 42e of the fourth embodiment described above calculates the End-To-End, i.e., the transmission path characteristics from the connecting party to the connecting destination, based on the connection information received from each connecting node device 1fX and 1fY and the transmission path information of the optical transmission path 52 corresponding to the connection destination address information contained in the connection request data. Alternatively, the following structure can be adopted.

[0295] The control units 12fX and 12fY of the connection node devices 1fX and 1fY calculate the transmission path characteristics based on the connection information of optical transmission paths 51 and 53, and send the calculated transmission path characteristics to the operation device 4e instead of the connection information. The transmission path design unit 42e of the operation device 4e calculates the transmission path characteristics of optical transmission path 52 based on the transmission path information of optical transmission path 52 stored in its internal storage area. Alternatively, the transmission path design unit 42e can calculate the estimated end-to-end transmission path characteristics based on the transmission path characteristics of optical transmission path 51 and optical transmission path 53 sent by the control units 12fX and 12fY, and the transmission path characteristics of optical transmission path 52 calculated based on the transmission path information of optical transmission path 52. Alternatively, the transmission path design unit 42e may not calculate the transmission path characteristics of the optical transmission path 52 based on the transmission path information of the optical transmission path 52. Instead, it may calculate the transmission path characteristics of the optical transmission path 52 in advance based on the transmission path information of the optical transmission path 52, store the calculated transmission path characteristics of the optical transmission path 52 in advance in the internal storage area, and read the transmission path characteristics of the optical transmission path 52 from the internal storage area instead of the processing of calculating the transmission path characteristics of the optical transmission path 52.

[0296] In the first to fourth embodiments described above, as well as other structural examples of each embodiment, the following structure may also be adopted. For example, the connection information generation units 38, 38a, and 38aX of the connection node devices 1, 1a, 1b, 1c, 1d, 1e, and 1fX perform multiple calculations of the transmission path information of the optical transmission path 51. In the fourth embodiment, the connection information generation unit 38aY of the connection node device 1fY performs multiple calculations of the transmission path information of the optical transmission path 53. The control unit 12 and the transmission path design units 42, 42a, 42b, 42c, 42d, and 42e obtain all the transmission path information calculated multiple times as described above through the connection information generation units 38, 38a, 38aX, and 38aY. The control unit 12 and the transmission path design units 42, 42a, 42b, 42c, 42d, and 42e calculate their respective transmission path characteristics based on the acquired transmission path information, and determine their respective transmission modes based on the calculated transmission path characteristics. Alternatively, the control unit 12 and the transmission path design units 42, 42a, 42b, 42c, 42d, and 42e select one transmission mode from the determined transmission modes using a majority decision method, that is, select the transmission mode with the most types of transmission modes, and set the selected transmission mode as the final transmission mode.

[0297] In the first to fourth embodiments and other structural examples of each embodiment described above, it is also possible to replace the single-wavelength light sources 36, 36X, and 36Y provided in the connected information processing units 13, 13a, 13aX, and 13aY with a single-wavelength light source 36, 36X, and 36Y, for example, using a wavelength-variable light source similar to the wavelength-variable light source 25aX, and whose wavelength of the generated continuous light is predetermined to be the basic wavelength. Alternatively, it is also possible to... Assume that, when the connection information processing units 13, 13a, 13aX, and 13aY are configured to the connection node devices 1, 1a, 1b, 1c, 1d, 1e, 1fX, and 1fY, the control units 12, 12a, 12b, 12c, 12e, 12fX, and 12fY of the connection node devices 1, 1a, 1b, 1c, 1e, 1fX, and 1fY output a wavelength specification signal to the wavelength-variable light source to specify the basic wavelength, thereby setting the wavelength of the wavelength-variable light source to the basic wavelength. Similarly, it can also be configured such that, instead of the single-wavelength light sources 25X, 25X-1 to 25X-m, 25Y, 25Y-1 to 25Y-n provided in the light transmitting and receiving units 21X, 21X-1 to 21X-m, 21Y, 21Y-1 to 21Y-n, a wavelength-variable light source of the same wavelength as the wavelength-variable light source 25aX is used, and the wavelength of the generated continuous light is predetermined to be the basic wavelength. Alternatively, it can be configured such that, in the light transmitting and receiving units 21X, 21X-1 to 21X-m, 21Y, 21Y-1 to 21Y-n, a wavelength-variable light source with the wavelength of the generated continuous light is predetermined to be the basic wavelength. When the timing of the optical communication devices 2X, 2X-1~2X-m, 2Y, 2cY, 2Y-1~2Y-n is set, the control units 20X, 20X-1~20X-m, 20Y, 20aY, 20Y-1~20Y-n of the optical communication devices 2X, 2X-1~2X-m, 2Y, 2Y-1~20Y-n output a wavelength specification signal to the wavelength-variable light source via the control units 71X, 71X-1~71X-m, 71Y, 71Y-1~71Y-n to set the wavelength of the wavelength-variable light source to the basic wavelength.

[0298] In the first to fourth embodiments described above, as well as other structural examples of each embodiment, the control units 71X, 71X-1 to 71X-m, 71aX-1 to 71aX-m, 71aX, and 71aY generate connection request data. Alternatively, the control units 20X, 20aX, 20X-1 to 20X-m, and 20Y may store the address information of their respective connected optical transceivers 21X, 21X-1 to 21X-m, 21aX-1 to 21aX-m, 21aX, and 21aY in their internal storage areas beforehand. This information may be used to generate connection request data instead of connection request indication signals. The generated connection request data may then be output to the control units 71X, 71X-1 to 71X-m, 71aX-1 to 71aX-m, 71aX, and 71aY, which are the connecting optical transceivers 21X, 21X-1 to 21X-m, 21aX-1 to 21aX-m, 21aX, and 21aY. In this case, the control units 71X, 71X-1 to 71X-m, 71aX-1 to 71aX-m, 71aX, and 71aY can obtain the connection request data output by the control units 20X, 20aX, 20X-1 to 20X-m, and 20Y, and output the obtained connection request data. Therefore, it is not necessary to generate connection request data.

[0299] In the first to fourth embodiments and other structural examples of each embodiment described above, the structure for implementing the connection information generation units 38, 38a, 38aX, and 38aY can also be configured as follows. For example, in the case of the connection node device 1 of the first embodiment, the connection information processing unit 13's IF unit 31, optical receiver 33, optical transmitter 35, and digital signal processing unit 32 can be configured as a single hardware package inserted into the main body of the connection node device 1. In this case, the connection information generation unit 38 and the control unit 12 can also be functional units generated by executing a computer program in the CPU (Central Processing Unit) of the main body of the connection node device 1. Alternatively, the structure can be as follows: a CPU is also included in the hardware package including the IF unit 31, optical receiver 33, optical transmitter 35, and digital signal processing unit 32; the functional unit of the connection information generation unit 38 is generated by executing a computer program in the CPU of the hardware package; and the functional unit of the control unit 12 is generated by executing a computer program in the CPU of the main body of the connection node device 1. Alternatively, the connection information generation units 38, 38a, 38aX, and 38aY can be configured not as software as described above, but as having an OTDR (Optical Time Domain Reflectometer) in the hardware package as the connection information generation unit 38, and acquiring transmission path information by utilizing the measurement of the OTDR.

[0300] Alternatively, the connection information generation units 38, 38a, 38aX, and 38aY can be located outside the connection information processing units 13, 13a, 13b, 13aX, and 13aY. In this case, the connection information generation units 38, 38a, 38aX, and 38aY can be integrated with the control units 12, 12a, 12b, 12c, 12d, 12e, 12fX, and 12fY. Alternatively, a portion of the processing of the connection information generation units 38, 38a, 38aX, and 38aY can be performed by any one or two of the digital signal processing units 32, 32a, 32aX, and 32aY and the control units 12, 12a, 12b, 12c, 12d, 12e, 12fX, and 12fY. Alternatively, the connection information generation units 38, 38a, 38aX, and 38aY can be configured such that a portion of the processing is performed by the digital signal processing units 32, 32a, 32aX, and 32aY, while the remaining processing is performed by the control units 12, 12a, 12b, 12c, 12d, 12e, 12fX, and 12fY, and the connection information generation units 38, 38a, 38aX, and 38aY are not present. Alternatively, the connection information generation units 38, 38a, 38aX, and 38aY can be configured such that the processing is performed by the digital signal processing units 32, 32a, 32aX, and 32aY, and the connection information generation units 38, 38a, 38aX, and 38aY are not present.

[0301] Alternatively, the digital signal processing units 23X, 23aX, 23X-1 to 23X-m, 23aX-1 to 23aX-m, 23Y, 23aY, 23Y-1 to 23Y-n, 23aY-1 to 23aY-n, control units 20X, 20aX, 20X-1 to 20X-m, 20Y, 20aY, 20Y-1 to 20Y-n, and control unit 71X in the above embodiments can be implemented by a computer. 71aX, 71X-1 to 71X-m, 71Y, 71aY, 71Y-1 to 71Y-n, transmission control unit 29X, digital signal processing units 32, 32a, 32aX, 32aY, connection information generation units 38, 38a, 38aX, 38aY, control units 12, 12a, 12b, 12c, 12d, 12e, 12fX, 12fY, and operating devices 4, 4a, 4b, 4c, 4d, 4e. In this case, the program for implementing this function can also be recorded on a computer-readable recording medium, and the function can be implemented by having the computer system read the program recorded on the recording medium and execute the program. Furthermore, the term "computer system" here is defined as including hardware such as the operating system and peripheral devices. Additionally, "computer-readable recording medium" refers to removable media such as floppy disks, optical disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into the computer system. Furthermore, "a recording medium that a computer can read" can also include media that dynamically maintains a program for a short period of time, such as communication lines used to transmit programs via networks like the Internet or telephone lines, or media that maintain a program for a certain period of time, such as volatile memory within a computer system that serves as a server or client in such cases. Additionally, the aforementioned program can be a part of a program used to implement the above-mentioned functions, and can also be implemented by combining it with programs already recorded in the computer system. It can also be implemented using programmable logic devices such as FPGAs (Field Programmable Gate Arrays).

[0302] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the specific structure is not limited to these embodiments and may also include designs within the scope of the present invention without departing from its spirit.

[0303] Industrial availability

[0304] It can be used when setting up optical routes through multiple optical transmission paths.

[0305] Explanation of reference numerals in the attached figures

[0306] 1: Connecting node device; 2X, 2Y: Optical communication device; 3: Connecting line; 11: Edge function unit; 12: Control unit; 13: Connecting information processing unit; 14: Output port switching unit; 21Y: Optical transmitting and receiving unit; 20Y: Control unit; 51, 52: Optical transmission path.

Claims

1. A connection node device, comprising: The connection information processing unit acquires connection information containing transmission path information, which is information related to the optical transmission path. An output port switching unit, connected to a first optical transmission path, a second optical transmission path, and the connection information processing unit, initially sets the connection destination of the first optical transmission path to the connection information processing unit; and The control unit transmits transmission mode information through the first optical transmission path to the optical transmission and receiving unit of the optical communication device connected to the first optical transmission path. This transmission mode information represents a transmission mode determined based on the connection information of the first optical transmission path obtained by the connection information processing unit from the optical signal transmitted by the optical transmission and receiving unit, the connection request data transmitted by the optical transmission and receiving unit in a manner included in the optical signal, and the transmission path information of the second optical transmission path. in, After the control unit sends the transmission mode information, the output port switching unit performs a switching process to switch the connection destination of the first optical transmission path from the connection information processing unit to the second optical transmission path.

2. The connection node device according to claim 1, wherein, There are multiple first optical transmission paths. The control unit sends, via the first optical transmission path, the connection information of the first optical transmission path that transmits the optical signal obtained by the connection information processing unit from the optical signal transmitted by the optical transmitter / receiver connected to any of the first optical transmission paths, the connection request data transmitted by the optical transmitter / receiver in a manner included in the optical signal, and the transmission mode information of the second optical transmission path determined by the transmission path information, to the optical transmitter / receiver shown as the connection party in the connection request data. After the control unit sends the transmission mode information, the output port switching unit performs a switching process to switch the connection destination of the first optical transmission path, which is connected to the optical transmitter / receiver unit as the connection party shown in the connection request data, from the connection information processing unit to the second optical transmission path.

3. The connection node device according to claim 1 or 2, wherein, In the first optical transmission path, it is configured to enable communication of optical signals using wavelength division multiplexing. In its initial state, the output port switching unit sets the connection destination of the basic wavelength predetermined in the first optical transmission path to the connection information processing unit. The control unit will transmit, via the basic wavelength of the first optical transmission path, to the optical transmission and receiving unit shown in the connection request data as the connection party, which is determined based on the connection information of the first optical transmission path obtained by the connection information processing unit from the optical signal transmitted by the optical transmission and receiving unit connected to the first optical transmission path at the basic wavelength, the connection request data transmitted by the optical transmission and receiving unit in a manner included in the optical signal, and the transmission path information of the second optical transmission path. After the control unit sends the transmission mode information, the output port switching unit performs a switching process to set the connection destination of the wavelength path of the first optical transmission path (shown in the connection request data as the connection party) to the wavelength path of the second optical transmission path (shown in the transmission mode information) to the wavelength path of the second optical transmission path.

4. The connection node device according to claim 1 or 2, wherein, There are multiple second optical transmission paths. The control unit sends transmission mode information, which represents the transmission mode determined based on the connection information of the first optical transmission path obtained by the connection information processing unit, the connection request data, and the transmission path information of the second optical transmission path corresponding to the connection destination shown in the connection request data, to the optical transmission and receiving unit through the first optical transmission path. After the control unit sends the transmission mode information, the output port switching unit performs the switching process of setting the second optical transmission path corresponding to the connection destination shown in the connection request data as the connection destination.

5. The connection node device according to claim 1 or 2, wherein, In the second optical transmission path, it is configured to enable communication of optical signals using wavelength division multiplexing. The control unit sends transmission mode information, which represents the transmission mode determined based on the connection information of the first optical transmission path obtained by the connection information processing unit, the connection request data, and the transmission path information of the second optical transmission path corresponding to the connection destination shown in the connection request data, to the optical transmission and receiving unit through the first optical transmission path. After the control unit sends the transmission mode information, the output port switching unit performs a switching process to set the wavelength path of the second optical transmission path corresponding to the connection destination shown in the connection request data, which includes the wavelength shown in the transmission mode information, as the connection destination.

6. The connection node device according to claim 5, wherein, The connection node device includes a wavelength conversion unit that converts the wavelength of the supplied light into a wavelength accepted from the control unit and outputs it. The optical transmitting and receiving unit has a light source that outputs light of a single wavelength. After the control unit sends the transmission mode information, the output port switching unit sets the switched connection destination to the wavelength conversion unit. The control unit outputs the wavelength shown in the transmission mode information to the wavelength conversion unit. The wavelength conversion unit receives the optical signal sent to the first optical transmission path by the optical transmission and reception unit via the output port switching unit, converts the wavelength of the received optical signal to the wavelength accepted by the control unit, and sends it to the second optical transmission path corresponding to the connection destination shown in the connection request data.

7. An optical transmission system, comprising: The connection node device according to claim 1; A first optical communication device is connected to the other end of a first optical transmission path to which one end is connected to the connection node device; and A second optical communication device is directly or indirectly connected to the connection node device via a second optical transmission path at one end of which is connected to the connection node device. In the optical transmission system, The first optical communication device includes an optical transmitting and receiving unit that receives the transmission mode information transmitted by the control unit of the connection node device through the first optical transmission path, and transmits and receives optical signals through the first optical transmission path according to the transmission mode indicated by the received transmission mode information. The second optical communication device includes an optical transmitting and receiving unit that receives the transmission mode information and transmits and receives optical signals through the second optical transmission path according to the transmission mode indicated by the received transmission mode information. After the control unit sends the transmission mode information to the first optical communication device through the first optical transmission path, the output port switching unit of the connection node device connects the optical transmission and reception units of the first optical communication device and the optical transmission and reception units of the second optical communication device through the switching process.

8. The optical transmission system according to claim 7, wherein, The second optical communication device is connected to the other end of the second optical transmission path. The control unit of the connection node device acquires the second optical transmission path, and based on the acquired transmission path information of the second optical transmission path, the connection information of the first optical transmission path acquired by the connection information processing unit, and the connection request data, generates transmission mode information for determining the transmission mode, and sends the generated transmission mode information to the first optical communication device through the first optical transmission path, and also sends the transmission mode information to the second optical communication device. The second optical communication device includes an optical transmitting and receiving unit that receives the transmission mode information sent by the control unit, and transmits and receives optical signals through the second optical transmission path in accordance with the transmission mode indicated by the received transmission mode information.

9. The optical transmission system according to claim 7, wherein, It has an operating device that can be connected to the connection node device. The operating device acquires the transmission path information of the second optical transmission path, and based on the acquired transmission path information of the second optical transmission path, the connection information of the first optical transmission path acquired by the connection information processing unit of the connection node device from the optical signal transmitted by the optical transmitter and receiver of the first optical communication device, and the connection request data transmitted by the optical transmitter and receiver of the first optical communication device in a manner included in the optical signal, generates transmission mode information for determining the transmission mode and sends it to the control unit of the connection node device. The first optical communication device includes an optical transmitting and receiving unit that receives transmission mode information from the operating device and transmitted through the first optical transmission path by the control unit of the connection node device, and transmits and receives optical signals through the first optical transmission path in the transmission mode indicated by the received transmission mode information.

10. The optical transmission system according to claim 9, wherein, The second optical communication device is connected to the other end of the second optical transmission path. The operating device is connected to the connection node device and the second optical communication device, and sends the transmission mode information to the control unit of the connection node device and the second optical communication device. The second optical communication device includes an optical transmitting and receiving unit that receives the transmission mode information sent by the operating device, and transmits and receives optical signals through the second optical transmission path in accordance with the transmission mode indicated by the received transmission mode information.

11. The optical transmission system according to claim 9, wherein, have: The third optical transmission path; and The second optical communication device is connected to the third optical transmission path. There are multiple connection node devices. The output port switching unit of the connection node device of one party is connected to the first optical transmission path, the second optical transmission path, and the connection information processing unit of this device. In the initial state, the connection destination of the first optical transmission path is set to the connection information processing unit of this device. The output port switching unit of the other connection node device, which is connected to the third optical transmission path and is any connection node device other than the aforementioned connection node device, is connected to the third optical transmission path, the other end of the second optical transmission path connected to the connection node device of the aforementioned device, and the connection information processing unit of this device. In the initial state, the connection destination of the third optical transmission path is set to the connection information processing unit of this device. The operating device is connected to both the connection node device of the first party and the connection node device of the other party. It acquires transmission path information of the second optical transmission path. Based on the acquired transmission path information of the second optical transmission path, the connection information of the first optical transmission path acquired by the connection information processing unit of the first connection node device from the optical signal transmitted by the optical transmitter / receiver unit of the first optical communication device, the connection request data transmitted by the optical transmitter / receiver unit of the first optical communication device in a manner included in the optical signal, the connection information of the third optical transmission path acquired by the connection information processing unit of the other connection node device from the optical signal transmitted by the optical transmitter / receiver unit of the second optical communication device, and the connection request data transmitted by the optical transmitter / receiver unit of the second optical communication device in a manner included in the optical signal, it generates transmission mode information for determining the transmission mode. The generated transmission mode information is then sent to the control unit of the first connection node device and the control unit of the other connection node device. The first optical communication device includes an optical transmitting and receiving unit that receives transmission mode information from the operating device and transmitted through the first optical transmission path by the control unit of the connection node device of the first party, and transmits and receives optical signals through the first optical transmission path according to the transmission mode indicated by the received transmission mode information. The second optical communication device includes an optical transmitting and receiving unit that receives transmission mode information from the operating device and transmitted through the third optical transmission path by the control unit of the other party's connection node device, and transmits and receives optical signals through the third optical transmission path according to the transmission mode indicated by the received transmission mode information. After the control unit of one of the connection node devices sends the transmission mode information to the optical transmitter / receiver unit of the first optical communication device through the first optical transmission path, the output port switching unit of the connection node device connects the first optical transmission path and the second optical transmission path by performing the switching process. After the control unit of the other party's connection node device sends the transmission mode information to the optical transmission and reception unit of the second optical communication device through the third optical transmission path, the output port switching unit of the other party's connection node device connects the second optical transmission path and the third optical transmission path by performing the switching process.

12. The optical transmission system according to claim 8, wherein, The control unit of the connection node device calculates transmission path characteristics based on the connection information obtained by the connection information processing unit and the transmission path information of the second optical transmission path corresponding to the connection destination shown in the connection request data. Based on the calculated transmission path characteristics, it generates transmission mode information for determining the transmission mode. Alternatively, it generates transmission mode information for determining the transmission mode based on the transmission path characteristics calculated according to the transmission path information of the second optical transmission path corresponding to the connection destination shown in the connection request data and the transmission path characteristics calculated according to the connection information obtained from the connection information processing unit.

13. The optical transmission system according to any one of claims 9 to 11, wherein, The operating device calculates transmission path characteristics based on the connection information obtained by the connection information processing unit and the transmission path information of the second optical transmission path corresponding to the connection destination shown in the connection request data. Based on the calculated transmission path characteristics, it generates transmission mode information for determining the transmission mode. Alternatively, it generates transmission mode information for determining the transmission mode based on the transmission path characteristics calculated according to the transmission path information of the second optical transmission path corresponding to the connection destination shown in the connection request data and the transmission path characteristics calculated according to the connection information obtained by the control unit of the connection node device from the connection information processing unit.

14. The optical transmission system according to any one of claims 7 to 11, wherein, The connection information processing unit of the connection node device connected to the first optical transmission path obtains the transmission path information of the first optical transmission path in the direction from the first optical communication device to the connection node device, or obtains the transmission path information of the first optical transmission path in the direction from the connection node device to the first optical communication device.

15. The optical transmission system according to claim 11, wherein, If the operating device does not receive connection information of the third optical transmission path and connection request data transmitted by the optical transmitting and receiving unit of the second optical communication device in a manner included in the optical signal from the other party's connection node device, the operating device sends a trigger signal to the other party's connection node device to enable the transmission of the connection information of the third optical transmission path and the connection request data.

16. The optical transmission system according to claim 11 or 15, wherein, The second optical communication device includes an optical transmitting and receiving unit that acquires information related to the third optical transmission path from an optical signal transmitted by the other party's connection node device, and transmits the acquired information related to the third optical transmission path to the other party's connection node device through the third optical transmission path. The connection information processing unit of the other party's connection node device receives information related to the third optical transmission path transmitted by the optical transmission receiving unit of the second optical communication device through the third optical transmission path, and obtains the transmission path information of the third optical transmission path in the direction from the other party's connection node device to the second optical communication device from the received information related to the third optical transmission path.

17. The optical transmission system according to any one of claims 7 to 10, wherein, When the connecting node device is the connecting node device according to claim 2 or 3. The plurality of optical transmitting and receiving units are connected to the first optical transmission path. The control unit of the connection node device sends initial setting information to the plurality of optical transmitting and receiving units through the first optical transmission path to avoid conflicts in the connection request data. The plurality of optical transmitting and receiving units receive optical signals containing the initial setting information through the first optical transmission path, and send the connection request data according to the received initial setting information.

18. The optical transmission system according to claim 7 or 10, wherein, The first optical communication device includes: Multiple optical transmitting and receiving units; and The transmission control unit adjusts the timing of the connection request data sent by the plurality of optical transmitters and receivers to avoid conflicts in the connection request data sent by the plurality of optical transmitters and receivers through the first optical transmission path.

19. The optical transmission system according to claim 7 or 10, wherein, If the optical transmitting and receiving unit connected to the first optical transmission path does not receive a response optical signal from the connection node device within a predetermined standby time after sending the connection request data, it stops the optical output for an arbitrarily determined time.

20. A connection method, wherein, The output port switching unit is connected to the first optical transmission path, the second optical transmission path, and the connection information processing unit. In the initial state, the connection destination of the first optical transmission path is set to the connection information processing unit. The connection information processing unit acquires connection information that includes transmission path information as information related to the optical transmission path. The control unit sends transmission mode information to the optical transmission and receiving unit of the optical communication device connected to the first optical transmission path through the first optical transmission path. The transmission mode information represents the transmission mode determined based on the connection information of the first optical transmission path obtained by the connection information processing unit from the optical signal sent by the optical transmission and receiving unit, the connection request data sent by the optical transmission and receiving unit in a manner included in the optical signal, and the transmission path information of the second optical transmission path. After the control unit sends the transmission mode information, the output port switching unit performs a switching process to switch the connection destination of the first optical transmission path from the connection information processing unit to the second optical transmission path.

Images