Optical communication device, optical communication system, and optical communication method

Abstract

An optical communication device includes an optical switch, a wavelength management control unit, and an optical switch control unit. The optical switch is connected to the plurality of transmission paths, and outputs an optical signal input from any one of the transmission paths to another transmission path. The wavelength management control unit allocates a wavelength corresponding to the communication destination to the subscriber device. The optical switch control unit controls the optical switch such that the optical signal transmitted from the subscriber device to which the wavelength has been allocated is output to a transmission path corresponding to a transfer destination on the path to the communication destination.

Description

[0001] This application is a divisional application. The name of the invention of the parent case is “Optical communication device, optical communication system and optical communication method”. The application date is September 29, 2020, and the application number is 202080089058.1. Technical Field

[0002] The present invention relates to an optical communication device, an optical communication system and an optical communication method.

[0003] This application claims priority to PCT / JP2019 / 051305 filed on December 26, 2019, PCT / JP2020 / 005782 filed on February 14, 2020, and PCT / JP2020 / 033760 filed on September 7, 2020, the contents of which are incorporated herein by reference. Background Art

[0004] The number of users who use high-speed Internet based on FTTH (Fiber To The Home) and mobile services continues to grow. High-speed Internet has become an indispensable thing in people's lives. On the other hand, in the backbone network that provides FTTH and mobile services, the network is constructed independently for each service. Therefore, it is inefficient in terms of operation. Therefore, an access network that accommodates multiple services with one device has been proposed (for example, refer to non-patent document 1). Furthermore, in order to realize an access network that can accommodate multiple services, PON (Passive Optical Network) such as WDM-PON (Wavelength Division Multiplexing PON) or TDM-PON (Time Division Multiplexing PON) using multiple wavelengths is standardized by ITU-T (International Telecommunication Union Telecommunication Standardization Sector) (for example, refer to non-patent document 2).

[0005] On the other hand, in the existing optical access system, the communication between the device on the subscriber side and the central office is connected to a higher-level core network. The device on the subscriber side is, for example, an ONU (Optical Network Unit). In addition, the connection with the core network is made via a terminal device located in a device on the central office side. The terminal device is, for example, an OLT (Optical Line Terminal). In the optical access connected to the core network through packet switching, the signal is processed to assign or delete user information, destination information, route processing, etc. When assigning or deleting user information and destination information, the optical signal is sometimes converted into an electrical signal at one time. Therefore, a certain degree of delay occurs in the communication. In addition, if the amount of data becomes larger, the signal is sometimes accumulated in the buffer, and priority control is performed. As a result, the delay becomes further increased. If the delay becomes larger, the quality of the optical service will be greatly reduced. Therefore, it is important to reduce the delay as much as possible.

[0006] In order to improve the quality of optical services and provide various services in optical access networks, it is necessary to reduce the delay that occurs. The delay can be greatly reduced by using optical switches that can perform processing such as routing without converting optical signals into electrical signals.

[0007] Prior art literature Non-patent literature Non-patent document 1: Shunji Kimura, "Elastic Lambda Aggregation Network (EλAN)-Proposal for Future Optical Access Network-", 201318th OptoElectronics and Communications Conference held jointly with 2013International Conference onPhotonics in Switching (OECC / PS), WP4-4, 2013; Non-patent document 2: "ITU-T G.989.1", International Telecommunication Union, 2013. Summary of the invention

[0008] Problems to be solved by the invention However, in routing using an optical switch, it is necessary to set a path of an optical signal corresponding to a destination of a subscriber device and further perform settings (wavelength, etc.) of a transceiver of the subscriber device.

[0009] In view of the above, an object of the present invention is to provide an optical communication device, an optical communication system, and an optical communication method capable of setting a path corresponding to a destination for a subscriber device and relaying an optical signal transmitted from the subscriber device according to the destination.

[0010] Solutions to Solve Problems One embodiment of the present invention is an optical communication device, which comprises: an optical switch connected to a plurality of transmission paths and outputting an optical signal input from any one of the transmission paths to the other transmission paths; a wavelength management control unit that allocates a wavelength corresponding to a communication destination to a subscriber device; and an optical switch control unit that controls the optical switch so that an optical signal sent from the subscriber device to which the wavelength is allocated is output to a transmission path corresponding to a forwarding destination on a path to the communication destination.

[0011] One embodiment of the present invention is an optical communication device, comprising: an optical switch connected to a plurality of transmission paths, outputting an optical signal input from any one of the transmission paths to the other transmission paths; a wavelength management control unit dynamically allocating a wavelength corresponding to a communication destination to a subscriber device; and an optical switch control unit controlling the optical switch so that the optical signal input from the transmission path is output to the transmission path corresponding to the communication destination specifically designated by a combination of the subscriber device that sent the input optical signal and the wavelength of the input optical signal.

[0012] One embodiment of the present invention is an optical communication system having multiple subscriber devices and the above-mentioned optical communication device, wherein the subscriber devices have any one or both of the following: an optical transmitting unit that transmits an optical signal of a wavelength assigned by the optical communication device; and an optical receiving unit that receives an optical signal of a wavelength assigned by the optical communication device.

[0013] One embodiment of the present invention is an optical communication method, which comprises: a forwarding step, in which an optical switch connected to a plurality of transmission paths outputs an optical signal input from any one of the transmission paths to the other transmission paths; an allocation step, in which a wavelength management control unit allocates a wavelength corresponding to a communication destination to a subscriber device; and an optical switch control step, in which the optical switch control unit controls the optical switch so that in the forwarding step, the optical signal sent from the subscriber device to which the wavelength is allocated is output to the transmission path corresponding to the forwarding destination on the path to the communication destination.

[0014] One embodiment of the present invention is an optical communication method, which comprises: a forwarding step, in which an optical switch connected to a plurality of transmission paths outputs an optical signal input from any one of the transmission paths to the other transmission paths; an allocation step, in which a wavelength management control unit dynamically allocates a wavelength corresponding to a communication destination to a subscriber device; and an optical switch control step, in which the optical switch control unit controls the optical switch so that in the forwarding step, the optical signal input from the transmission path is output to the transmission path corresponding to the communication destination, wherein the communication destination is specifically specified by a combination of the subscriber device that sent the input optical signal and the wavelength of the input optical signal.

[0015] Effects of the Invention According to the present invention, it is possible to set a path that can be used in accordance with a destination for a subscriber device, and to relay an optical signal transmitted from the subscriber device according to the destination. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a diagram showing a configuration example of an optical communication system according to an embodiment of the present invention; Figure 2 is a diagram showing an example of light SW according to an embodiment; Figure 3 is a diagram showing an example of light SW according to an embodiment; Figure 4 is a diagram showing an example of light SW according to an embodiment; Figure 5 is a diagram showing an example of light SW according to an embodiment; Figure 6 is a diagram showing an example of light SW according to an embodiment; Figure 7 1 is a diagram showing an example of routing before wavelength change in the optical SW according to the embodiment; Figure 8 1 is a diagram showing an example of routing after wavelength change in the optical SW according to the embodiment; Fig. 9 is a diagram showing an example of light SW according to an embodiment; Fig.10 is a diagram showing an example of light SW according to an embodiment; Fig.11 is a diagram showing an example of light SW according to an embodiment; Fig.12 is a diagram showing an example of light SW according to an embodiment; Fig.13 is a diagram showing an example of light SW according to an embodiment; Fig.14is a diagram showing an example of light SW according to an embodiment; Fig.15 is a diagram showing an example of an access topology according to an embodiment; Fig.16 is a diagram showing an example of an access topology according to an embodiment; Fig.17 is a diagram showing an example of an access topology according to an embodiment; Fig.18 is a diagram showing an example of an access topology according to an embodiment; Fig.19 is a diagram showing an example of an access topology according to an embodiment; Fig. 20 is a diagram showing an example of an access topology according to an embodiment; Fig.21 is a diagram showing an example of an access topology according to an embodiment; Fig. 22 is a diagram showing an example of an access topology according to an embodiment; Fig.23 is a diagram showing an example of an access topology according to an embodiment; Fig.24 is a diagram showing an example of scalability required of an optical SW according to an embodiment; Fig.25 is a diagram showing an example of optical SW scalability according to an embodiment; Fig.26 is a diagram showing an example of optical SW scalability according to an embodiment; Fig. 27 is a diagram showing a configuration example of an optical access system according to a first embodiment; Fig.28 is a diagram showing an example of a SW connection table according to the embodiment; Fig.29 is a diagram showing an example of a user wavelength table according to the embodiment; Fig.30 is a diagram showing an example of an inter-office wavelength table according to the embodiment; Fig.31 is a diagram showing a configuration example of a subscriber device according to the embodiment; Fig.32 is a diagram showing a configuration example of a subscriber device according to the embodiment; Fig.33 is a flowchart showing an initial setting process of the optical access system according to the embodiment; Fig.34 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.35 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.36 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.37 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.38 is a diagram showing a configuration example of an optical access system according to a second embodiment; Fig.39 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.40 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.41 is a diagram showing a configuration example of an optical access system according to a third embodiment; Fig.42 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.43 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.44 is a diagram showing a configuration example of an optical access system according to a fourth embodiment; Fig.45 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.46 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.47 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.48 is a diagram showing a configuration example of an optical access system according to a fifth embodiment; Fig.49 is a diagram showing a configuration example of an optical access system according to a sixth embodiment; Fig.50 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.51 is a diagram showing a configuration example of an optical access system according to a seventh embodiment; Fig.52 is a diagram showing a configuration example of an optical access system according to an eighth embodiment; Fig.53 is a diagram showing a configuration example of an optical access system according to the embodiment; Fig.54 is a diagram showing a structural example of a shutter device according to this embodiment; Fig.55is a diagram showing a structural example of a shutter device according to this embodiment; Fig.56 is a diagram for explaining the operation of the optical access system according to the embodiment; Fig.57 It is a diagram showing a configuration example of an optical access system according to this embodiment. DETAILED DESCRIPTION

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in a plurality of drawings, the same reference numerals are given to the same parts, and their descriptions are omitted. In this embodiment, according to the connection request from each subscriber device, the wavelength used by the subscriber device is allocated in cooperation with the wavelength controller, the optical switch controller, and the management database that manages the connection information of all subscribers. At this time, a device for controlling the subscriber device is used to send setting information such as the wavelength used to each subscriber device. For example, the control device and the subscriber device communicate using a control signal that is lower than the main signal, i.e., the optical signal between the subscriber devices, and can be superimposed on the main signal. Thus, the setting change and monitoring can be performed without affecting the main signal. In addition, in this embodiment, the optical switch is controlled so that the optical signal sent from the subscriber device to which the wavelength is allocated is output to the transmission path corresponding to the forwarding destination on the path to the communication destination. In this embodiment, for example, in the case where the wavelength is used as the destination information, the optical switch is controlled so that routing is performed by using the wavelength as the destination information. Thus, a path corresponding to a destination is set for the subscriber device, and the optical signal transmitted from the subscriber device is relayed using the path according to the destination. In addition, delays caused by processing of adding or deleting user information and destination information and routing processing when forwarding packets can be reduced.

[0018] In addition, as destination information, a subscriber device, an input port, a set of a subscriber device and a wavelength, a set of an input port and a wavelength, or a set of an input port, a subscriber device, and a wavelength may be used. In the following embodiment, a case where a set of a subscriber device and a wavelength is used as destination information is mainly described.

[0019] Figure 1: is a diagram showing a structural example of an optical communication system 1 of the present embodiment. The optical communication system 1 has a plurality of optical SWs (switches) 10. Although only two optical SWs 10 are shown in the figure, the number of optical SWs 10 is arbitrary. The optical SWs 10 are connected to the control unit 20. The optical SWs 10 communicate with other optical SWs 10 via the optical communication network 30. In the optical communication network 30, for example, a WDM (Wavelength Division Multiplexing) network including various topologies can be used. One or more subscriber devices 40 are connected to the optical SWs 10. The subscriber device 40 is connected to the optical SWs 10 via an optical access network such as a PON (Passive Optical Network). The subscriber device 40 has an optical transceiver 41. The optical transceiver 41 is an example of the structure of an optical transmitting unit and an optical receiving unit in the subscriber device. The optical transceiver 41 has an optical transmitter (Tx) 42 and an optical receiver (Rx) 43. The optical transceiver 41 is a wavelength-variable optical transceiver. As the optical transceiver 41 , for example, a conventional optical transceiver with an AMCC (Auxiliary Management and Control Channel) function can be used.

[0020] The control unit 20 has an optical transceiver 21. The optical transceiver 21 is an example of the structure of the optical transmitting unit and the optical receiving unit in the control unit 20. The optical transceiver 21 has an optical transmitter (Tx) 22 and an optical receiver (Rx) 23. The optical transceiver 21 is a variable wavelength optical transceiver. The control unit 20 stores a wavelength management table. The wavelength management table is data showing the wavelength assigned to each subscriber device 40. The control unit 20 uses the AMCC function to assign the wavelength used by the subscriber device 40 in communication. In the following, the communication between the subscriber device 40 and the control unit 20 is exemplified by the AMCC function, but it is not limited to this.

[0021] In order to allocate a wavelength corresponding to a destination to the subscriber device 40, first, the optical transceiver 41 of the subscriber device 40 and the optical transceiver 21 of the control unit 20 communicate using AMCC. The control unit 20 refers to the wavelength table and selects a wavelength allocated to the subscriber device 40 according to the destination. As an example, the control unit 20 selects a wavelength from an idle wavelength that is not used for other paths on a link that performs wavelength division multiplexing on a path. In addition, the control unit 20 can allocate a separate wavelength to the subscriber device 40. The control unit 20 sets the selected wavelength to the subscriber device 40 by using a control signal of AMCC. Thereafter, the control unit 20 switches the optical SW 10 so that routing corresponding to the destination of the optical signal sent from the subscriber device 40 is performed. For example, when the wavelength is used as the destination information, the control unit 20 switches the optical SW so that routing is performed to the destination indicated by the wavelength. Thus, the relative subscriber devices 40 are connected.

[0022] The optical SW 10 is provided in, for example, an optical gateway (GW). Figure 2 to Figure 14 An example of the optical SW 10 included in the optical GW will be described.

[0023] Figure 2 : is a diagram showing a structural example of the optical SW10a. The optical SW10a is connected to a plurality of transmission paths 50, and outputs an optical signal input from any one of the transmission paths 50 to other transmission paths 50. The transmission path 50 is, for example, an optical fiber. The optical SW10a has ports 11-1-1 to 11-1-P (P is an integer greater than or equal to 2) and ports 11-2-1 to 11-2-Q (Q is an integer greater than or equal to 2). When any one of the ports 11-1-1 to 11-1-P is referred to collectively or not specifically, it is recorded as port 11-1, and when any one of the ports 11-2-1 to 11-2-Q is referred to collectively or not specifically, it is recorded as port 11-2. The transmission path 50 connected to the port 11-1 is recorded as the transmission path 50-1, and the transmission path 50 connected to the port 11-2 is recorded as the transmission path 50-2.

[0024] Each port 11-1 is connected to a subscriber device 40 via a transmission path 50-1. Each port 11-2 is connected to a subscriber device 40 via a transmission path 50-2. The subscriber device 40 is, for example, an ONU. The transmission path 50-2 may also be connected to an optical communication network 30 as an upper network. In this case, the direction of the subscriber device 40 connected via the transmission path 50-1 is the downstream direction, and the direction of the upper network connected via the transmission path 50-2 is the upstream direction. In addition, other optical communication devices such as the optical SW 10 may be provided in the transmission path 50-2.

[0025] The ports 11-1-1, 11-1-2, 11-1-3, ... are connected to the subscriber devices 40a-1, 40a-2, 40a-3, ... as the subscriber devices 40 for the location A via the transmission path 50-1, respectively. When any one of the subscriber devices 40a-1, 40a-2, 40a-3, ... is collectively referred to or not specifically specified, it is described as the subscriber device 40a. Any port 11-2 (in this figure, the port 11-2-1) is connected to the wavelength management control unit 25 described later. Some of the ports 11-2-i, 11-2-(i+1), 11-2-(i+2), ... are connected to the subscriber devices 40b-1, 40b-2, 40b-3, ... as the subscriber devices 40 for the location B via the transmission path 50-2, respectively (i is an integer greater than or equal to 2). When any one of the subscriber devices 40b-1, 40b-2, 40b-3, ... is collectively referred to or not specified, it is described as the subscriber device 40b. Ports 11-2-j, 11-2-(j+1), 11-2-(j+2), ..., which are a part different from the port 11-2 of the subscriber device 40 connected to the ground B, are connected to the subscriber devices 40c-1, 40c-2, 40c-3, ..., which are the subscriber devices 40 of the ground C, via the transmission path 50-2 (j is an integer greater than or equal to 2). When any one of the subscriber devices 40c-1, 40c-2, 40c-3, ... is collectively referred to or not specified, it is described as the subscriber device 40c. The optical SW 10a outputs the optical signal input from the port 11-1 to the port 11-2, and outputs the optical signal input from the port 11-2 to the port 11-1. Here, it is also possible to configure that the subscriber device 40 for the site A, the subscriber device 40 for the site B, and the subscriber device 40 for the site C are connected via another optical communication device such as an optical SW or an optical communication network 30 .

[0026] The optical SW 10a is connected to the control unit 20. The control unit 20 includes a wavelength management control unit 25 and an optical SW control unit 26. The wavelength management control unit 25 receives a request for wavelength allocation from a subscriber device 40 via an optical signal, performs a wavelength allocation process, allocates a wavelength corresponding to a communication destination to the subscriber device 40 that has sent the request, and notifies the subscriber device 40 of the allocated wavelength via an optical signal. For example, the wavelength management control unit 25 can dynamically allocate a wavelength corresponding to a communication destination to the subscriber device 40 that has sent the request. Preferably, in the optical signal transmitted and received between the wavelength management control unit 25 and the subscriber device 40, an overlapping method of management control signals that does not depend on the communication protocol of the optical signal (main signal) between the subscriber devices 40 is used. In the optical signal transmitted and received between the wavelength management control unit 25 and the subscriber device 40, for example, a protocol-free AMCC is used.

[0027] During the wavelength assignment process, the optical SW control unit 26 controls the optical SW 10a so that the optical signal is transmitted and received between the subscriber device 40 and the wavelength management control unit 25. After the wavelength assignment process, the optical SW control unit 26 controls the optical SW 10a so that the optical signal input from the transmission path 50 is output to the transmission path 50-2 corresponding to the communication destination that is specifically specified by the combination of the subscriber device 40 that transmitted the input optical signal and the wavelength of the input optical signal.

[0028] Each transmission path 50-2 is provided with a monitoring circuit 60. In this figure, only one monitoring circuit 60 is shown. The monitoring circuit 60 is an example of a monitoring unit. The monitoring circuit 60 has a power divider 61. The power divider 61 branches the optical signal transmitted in the transmission path 50-2. The monitoring circuit 60 monitors the optical signal branched by the power divider 61. The monitoring circuit 60 generates monitoring information based on the monitoring result and outputs the generated monitoring information. The monitoring information is information showing the monitoring result or information obtained from the monitoring result. As an output destination of the monitoring information, for example, the control unit 20 can be cited. In addition, in the communication with other subscriber devices 40, the control signal sent by the subscriber device 40 can be branched by using the power divider 61, or the control signal can be superimposed on the signal between the subscriber devices 40 and sent.

[0029] Furthermore, when the subscriber device 40 is connected to the transmission path 50-2, the control unit 20 may be connected to the port 11-1. Alternatively, when the subscriber device 40 is connected to the transmission path 50-2, the subscriber device 40 connected to the transmission path 50-2 may be connected to the control unit 20 via the return transmission path 73. The return transmission path 73 is an optical fiber that inputs an optical signal output from the port 11-1-p1 to another port 11-1-p2 (p1, p2 are integers greater than 1 and less than P). In this case, an optical signal transmitted from the subscriber device 40b or 40c is input to the optical SW 10a via the transmission path 50-2. The optical SW 10a outputs the optical signal input from the transmission path 50-2 to the port 11-1-p1, and inputs the optical signal transmitted in the return transmission path 73 from the port 11-1-p2. The optical SW 10a outputs the optical signal input from the port 11-1-p2 to the control unit 20 from the port 11-2-1. Thereby, the subscriber device 40 b or 40 c and the control unit 20 are connected.

[0030] The wavelength management control unit 25 may also perform a wavelength change process for instructing a change of wavelength to the subscriber device 40 that has undergone the wavelength allocation process. For example, the wavelength management control unit 25 specifies the subscriber device 40 to be changed in wavelength based on the monitoring information output from the monitoring circuit 60, and performs the wavelength change process on the specified subscriber device 40. During the wavelength change process, the optical SW control unit 26 controls the optical SW 10a so that an optical signal is transmitted and received between the subscriber device 40 and the wavelength management control unit 25. After the wavelength change process, when an optical signal of a changed wavelength is input from the subscriber device 40, the optical SW control unit 26 controls the optical SW 10a so that the input optical signal is output to the transmission path 50-2 corresponding to the communication destination. For example, after the wavelength change process, the optical SW control unit 26 receives an optical signal of a changed wavelength from the subscriber device 40, and controls the optical SW 10a so that the input optical signal is output to the transmission path 50-2 corresponding to the communication destination using the combination of the subscriber device 40 of the transmission source and the wavelength before the change. Alternatively, the optical SW control unit 26 may control the optical SW 10a so that the optical signal transmitted from the subscriber device 40 at the transmission source using the changed wavelength is output to a transmission path 50-2 different from that before the wavelength change. In this case, the subscriber device 40 at the communication destination is different before and after the wavelength change process. In addition, the wavelength management control unit 25 may receive a request for wavelength change from a subscriber device 40 during communication or after the communication is completed, and perform wavelength change processing on the subscriber device 40 at the request source. Through the wavelength change processing, both the wavelength used by the subscriber device 40 in transmission and the wavelength used in reception may be changed, or either one may be changed.

[0031] Figure 3 1 is a diagram showing a configuration example of an optical SW 10b having a return circuit for return communication. Figure 2 The same parts as those of the light SW10a shown in the figure are denoted by the same reference numerals, and their description is omitted. Figure 3 In the embodiment, the control unit 20 is omitted. The optical SW 10b is connected to the return transmission path 51. The return transmission path 51 is an optical fiber that inputs the optical signal output from the port 11-2 to another port 11-2. Thus, the optical SW 10b can perform return communication.

[0032] Furthermore, in the case where the port of the output destination of the optical signal is set by a combination of the subscriber device 40 of the sending source and the wavelength, the destination can be made different in the direction from port 11-1 to port 11-2 connected to the return transmission path 51, and in the direction from port 11-2 connected to the return transmission path 51 to port 11-1.

[0033] Figure 41 is a diagram showing a configuration example of an optical SW 10c for performing uplink multicast. Figure 2 The same parts as those of the light SW10a shown in the figure are denoted by the same reference numerals, and their description is omitted. Figure 4 , the description of the control unit 20 is omitted. The optical SW 10c has a distribution unit 58, which distributes the optical signal output from the port 11-2 into a plurality of optical signals and inputs the distributed plurality of optical signals to different ports 11-1. The distribution unit 58 is an example of a first distribution unit. Figure 4 In the embodiment, the optical SW10c inputs the optical signal output from the port 11-2 to the other port 11-2 via the return transmission path. The optical SW10c outputs the input optical signal to the port 11-1 connected to the 1×N power splitter 71. The optical signal output from the port 11-1 is distributed by the power splitter 71 and input to multiple other ports 11-1. The optical SW10c outputs the optical signals input from these multiple ports 11-1 to different ports 11-2. In addition, bidirectional communication can also be performed. The optical signal in the downstream direction is routed in the opposite direction to the upstream direction.

[0034] Furthermore, the optical SW 10c may input optical signals of multiple wavelengths from the port 11-1. In this case, the optical SW 10c distributes the optical signals of multiple wavelengths input from the port 11-1 through the distribution unit 58, and outputs the distributed optical signals to each subscriber device 40 connected to the port 11-2 or to a transmission path connected to another ground. The subscriber device 40 connected to the port 11-2 selects an optical signal of a predetermined wavelength from among the optical signals of multiple wavelengths and receives it. In addition, the transmission path connected to another ground may directly transmit the optical signals of multiple wavelengths, or may transmit the optical signals of multiple wavelengths transmitted by the transmission path described later. Figure 6 The WDM device shown selects the wavelength of an optical signal.

[0035] Figure 5 1 is a diagram showing a configuration example of an optical SW10d for performing downlink multicast. Figure 2 The same parts as those of the light SW10a shown in the figure are denoted by the same reference numerals, and their description is omitted. Figure 5 The control unit 20 is omitted in the description. The optical SW10d has a distribution unit 59, which distributes the optical signal output from the port 11-1 into a plurality of optical signals and inputs the distributed plurality of optical signals to different ports 11-2. The distribution unit 59 is an example of a second distribution unit. Figure 5In the embodiment, the optical SW10d inputs the optical signal output from the port 11-1 to another port 11-1 via the return transmission path. The optical SW10d outputs the input optical signal to the port 11-2 connected to the 1×N power splitter 72. The optical signal output from the port 11-2 is divided by the power splitter 72 and input to a plurality of other ports 11-2. The optical SW10d outputs the optical signals input from the plurality of ports 11-2 to different ports 11-1.

[0036] Furthermore, the optical SW 10d may input optical signals of multiple wavelengths from the port 11-2. In this case, the optical SW 10c distributes the optical signals of multiple wavelengths input from the port 11-2 through the distribution unit 59, and outputs the distributed optical signals to each subscriber device 40 connected to the port 11-1. Each subscriber device 40 connected to the port 11-1 selects and receives an optical signal of a predetermined wavelength from among the received optical signals of multiple wavelengths.

[0037] Figure 6 FIG. 1 is a diagram showing a configuration example of an optical SW10e for WDM transmission. Figure 2 The same parts as the optical SW10a shown are marked with the same figure marks, and their descriptions are omitted. The optical SW10e is connected to one or more WDM devices 80. The WDM device 80 is an example of a wavelength combining and demultiplexing device. The WDM device 80 combines optical signals of different wavelengths output from each of the multiple ports 11-2, and outputs them to the multiplexed communication transmission path 90. In addition, the WDM device 80 demultiplexes the optical signals received via the multiplexed communication transmission path 90 according to the wavelength, and inputs the demultiplexed optical signals to the multiple ports 11-2 respectively. In this way, the WDM device 80 has the functions of a combining device and a demultiplexing device. The combining device combines optical signals of different wavelengths output from the multiple ports 11-2 of the optical SW10e and outputs them to the multiplexed communication transmission path 90, and the demultiplexing device demultiplexes the optical signals received via the multiplexed communication transmission path 90 according to the wavelength and inputs the demultiplexed optical signals to different multiple ports 11-2 of the optical SW10e respectively. The optical SW10e that performs WDM transmission can also transmit Figure 3 The illustrated return transmission path 51 is connected to the port 11 - 2 which is not connected to the WDM device 80 .

[0038] The multiplexed communication transmission path 90 is provided with a monitoring circuit 65. The monitoring circuit 65 includes a power splitter 66 and WDM devices 67 and 68. The power splitter 66 branches an optical signal transmitted in the multiplexed communication transmission path 90. The WDM device 67 branches an upstream optical signal branched from the power splitter 66. The WDM device 68 branches a downstream optical signal branched from the power splitter 66. The monitoring circuit 65 monitors the optical signal branched by the WDM devices 67 and 68. The monitoring circuit 65 generates monitoring information based on the monitoring result and outputs the generated monitoring information. The monitoring information is information showing the monitoring result or information obtained from the monitoring result. For example, when an abnormality in the communication status between the subscriber devices 40 is detected by monitoring the optical signal, the monitoring circuit 65 outputs monitoring information in which the meaning of the abnormality in the communication status and information specifying the subscriber device 40 in which the abnormality in the communication status has occurred are set. As an output destination of the monitoring information, for example, the control unit 20 can be cited.

[0039] The monitoring circuit 65 may include a power divider 69 in each transmission path between the port 11-2 and the WDM device 80. The power divider 69 branches the optical signal transmitted in the transmission path between the port 11-2 and the WDM device 80, and outputs the branched optical signal to the control unit 20.

[0040] The wavelength management control unit 25 may also perform a wavelength change process for instructing a change of wavelength to the subscriber device 40 that has undergone the wavelength allocation process. For example, the wavelength management control unit 25 specifies the subscriber device 40 to be changed in wavelength based on the monitoring information output from the monitoring circuit 65, and performs the wavelength change process on the specified subscriber device 40. During the wavelength change process, the optical SW control unit 26 controls the optical SW 10e so that an optical signal is received and transmitted between the subscriber device 40 and the wavelength management control unit 25. After the wavelength change process, when an optical signal of a changed wavelength is input from the subscriber device 40, the optical SW control unit 26 controls the optical SW 10e so that the input optical signal is output from the port 11-2 corresponding to the communication destination. In addition, the wavelength management control unit 25 may receive a request for wavelength change from a subscriber device 40 during communication or after the communication is completed, and perform the wavelength change process on the subscriber device 40 of the request source.

[0041] use Figure 7 and Figure 8 An example of wavelength change in the light SW10e will be described. Figure 71 is a diagram showing an example of routing before wavelength change in the optical SW 10e. The optical SW 10e is connected to the subscriber devices 40 40a-1, 40a-2, 40a-3, ..., which are the ground A. The WDM device 80 connected to the ground B is described as a WDM device 80b, and the WDM device 80 connected to the ground C is described as a WDM device 80c. The WDM device 80b transmits and receives the wavelength λ between the optical SW 10e. 1 ~λ 10 The WDM device 80c transmits and receives the optical signal of wavelength λ between the optical SW10e and the optical SW10e. 11 ~λ 20 light signal.

[0042] exist Figure 7 Before the wavelength is changed, the wavelength λ input from the subscriber device 40a-1 to the optical SW10e is 1 The optical signal of wavelength λ input from subscriber device 40a-2 2 The optical signals of the subscriber device 40a-2 are respectively output from different ports 11-2 to the WDM device 80b. During or after communication, the subscriber device 40a-2 sends a request for wavelength change to the wavelength management control unit 25 through a control signal. When receiving the request for wavelength change from the subscriber device 40a-2, the wavelength management control unit 25 instructs the subscriber device 40a-2 to change the wavelength λ. 10 The optical SW control unit 26 controls the optical SW 10e so that the wavelength λ received from the subscriber device 40a-2 is 10 The optical signal with wavelength λ 10 The corresponding port 11-2 outputs the signal to the WDM device 80b. Furthermore, the wavelength management control unit 25 may further change the wavelength used by the subscriber device 40a-2 for reception.

[0043] Furthermore, after the wavelength change process, the optical SW control unit 26 may control the optical SW 10e so that the optical signal transmitted from the subscriber device 40 at the transmission source using the changed wavelength is output to a WDM device 80 different from that before the wavelength change. Figure 8 FIG. 1 is a diagram showing an example of routing after the wavelength of the optical SW10e is changed when the WDM device 80 of the output destination is changed. Figure 7 As shown, subscriber device 40a-1 uses wavelength λ 1 To communicate, the subscriber device 40a-2 uses wavelength λ 2 or wavelength λ 10 During or after communication, the subscriber device 40a-2 sends a wavelength change request to the wavelength management control unit 25 through a control signal. When receiving the wavelength change request from the subscriber device 40a-2, the wavelength management control unit 25 instructs the subscriber device 40a-2 to change the wavelength11 The optical SW control unit 26 controls the optical SW 10e so that the wavelength λ received from the subscriber device 40a-2 is changed. 11 The optical signal with wavelength λ 11 The corresponding port 11-2 outputs the signal to the WDM device 80c. Furthermore, the wavelength management control unit 25 may further change the wavelength used by the subscriber device 40a-2 for reception.

[0044] When the subscriber device 40a-2 uses the wavelength as the destination information and does not change the wavelength used for reception, the wavelength management control unit 25 may operate as follows. When the wavelength is not used as the destination information, the following is not followed.

[0045] (1) The wavelength management control unit 25 releases the transmission wavelength used by the subscriber device 40 at the site B, which is the communication destination before the wavelength switching. By releasing the transmission wavelength, the path from the subscriber device 40a-2 with the wavelength as the destination information to the subscriber device 40 at the site B is reset. Thereafter, the wavelength management control unit 25 reallocates the wavelength that has become an idle wavelength due to the release to receive a signal from the subscriber device 40 at the site C, which is the new communication destination, to the subscriber device 40a-2. This is performed when the wavelength used by each subscriber device 40 is unique and no wavelength other than the idle wavelength is allocated.

[0046] (2) Before and after the wavelength of the subscriber device 40a-2 is changed, when the subscriber device 40 connected via a different multiplexed communication transmission path 90 becomes the communication destination, the wavelength used before the wavelength change can be directly reused. However, although the wavelength is used as the destination information, for example, in the case of different transmission paths or when the input port or output port of the optical switch is different, even the same wavelength is handled as a different path. In order to achieve the above-mentioned reuse, for example, "input transmission path" or "output transmission path" or "combination of all transmission paths constituting the path" is added to the parameters that serve as conditions for determining the output destination of the optical signal. For example, the output destination is determined by the combination of the transmission path or port to which the optical signal is input and the wavelength of the optical signal, and the combination of the transmission path or port to which the optical signal is input, the subscriber device 40 that transmits the optical signal, and the wavelength of the optical signal.

[0047] In the above description, the wavelength change process performed when the subscriber device 40 requests the wavelength change is described. However, the wavelength change process performed based on the monitoring information is also the same.

[0048] use Figures 9 to 12 The optical SW that performs WDM transmission and multicast will be described. Fig. 9 1 is a diagram showing a configuration example of an optical SW10f that performs WDM transmission and multicast in the upstream direction. Fig. 9 In the example, the light SW10f performs multicast in the upstream direction through a single wavelength. Fig. 9 As shown, light SW10f has Figure 4 The same distribution section 58. Fig. 9 In the example, multicast is performed to ground B and ground C. The optical SW10f outputs the optical signal input from the port 11-1 connected to the subscriber device 40 from the port 11-2 connected to the return transmission path, and inputs the optical signal transmitted in the return transmission path from the other port 11-2. The optical SW10f outputs the input optical signal from the port 11-1 connected to the 1×N power splitter 71. The optical SW10f inputs the optical signals distributed by the 1×N power splitter 71 from the plurality of ports 11-1, outputs one of the input optical signals to the port 11-2 connected to the ground B, and outputs the other optical signal to the port 11-2 connected to the ground C.

[0049] Furthermore, the subscriber device 40 may also output a WDM signal. For example, the subscriber device 40 outputs a wavelength λ 1 The optical signal and wavelength λ 2 In addition, the multiple transmission paths between the WDM device 80b and the optical SW10f transmit and receive wavelengths λ in order from the top. 1 , 2 Similarly, the multiple transmission paths between the WDM device 80c and the optical SW10f transmit and receive the wavelength λ in order from the top. 1 , 2 ,…optical signal.

[0050] The wavelength λ input from the port 11-1 connected to the subscriber device 40 is distributed by the distribution unit 58. 1 and wavelength λ 2 The optical SW10f outputs the distributed WDM signal to the port 11-2 connected to the WDM device 80b, which has the same wavelength as λ. 1 The optical SW 10f outputs the other WDM signal distributed to the port 11-2 connected to the WDM device 80c corresponding to the wavelength λ. 2 The WDM device 80b filters the 1 The corresponding port inputs the WDM signal, cuts off the wavelength λ 2 , so that the wavelength λ 1 The optical signal passes through and is output to the multiplexed communication transmission path 90. The WDM device 80c filters the optical signal with the wavelength λ 2 The corresponding port inputs the WDM signal, cuts off the wavelength λ1 , so that the wavelength λ 2 The optical signal passes through and is output to the multiplexed communication transmission path 90.

[0051] Fig.10 1 is a diagram showing a case where the light SW10f performs multicast in the upstream direction to multiple grounds using multiple wavelengths. By providing one or more 1×M power splitters 55 in the transmission path 50-1, multiple subscriber devices 40 can be connected to the transmission path 50-1 connected to one port 11-1. Fig.10 In FIG. 5 , as a plurality of subscriber devices 40a-1, subscriber devices 40a-1-1, 40a-1-2, ... are connected to one transmission path 50-1. Subscriber devices 40a-1-1, 40a-1-2, ... use different wavelengths. Here, subscriber device 40a-1-1 transmits a wavelength λ 1 The subscriber device 40a-1-2 transmits an optical signal of wavelength λ 2 The optical SW10f inputs the wavelength λ transmitted by the subscriber device 40a-1-1 from the port 11-1. 1 The wavelength λ of the optical signal transmitted by the subscriber device 40a-1-2 2 The optical SW10f outputs the input optical signal from the port 11-2 connected to the return transmission path, and inputs the optical signal transmitted in the return transmission path from the other port 11-2. The optical SW10f outputs the input optical signal from the port 11-1 connected to the 1×N power divider 71. The optical SW10f inputs the optical signals distributed by the 1×N power divider 71 from multiple ports 11-1.

[0052] The optical SW 10f outputs the optical signal divided by the power divider 71 to the port 11-2 connected to the WDM device 80b, which has the same wavelength as λ. 1 The corresponding port 11-2 and the wavelength λ 2 The optical SW 10f outputs the optical signal divided by the power divider 71 to the port 11-2 connected to the WDM device 80c corresponding to the wavelength λ. 1 The corresponding port 11-2 and the wavelength λ 2 The WDM device 80b filters the 1 The corresponding port input optical signal has a wavelength λ 1 The optical signal passes through and is output to the multiplexed communication transmission path 90, and is filtered from the 2 The corresponding port input optical signal has a wavelength λ 2 The optical signal of the wavelength λ is passed through and output to the multiplexed communication transmission path 90. Similarly, the WDM device 80c filters the optical signal corresponding to the wavelength λ 1 The corresponding port input optical signal has a wavelength λ1 The optical signal passes through and is output to the multiplexed communication transmission path 90, and is filtered from the 2 The corresponding port input optical signal has a wavelength λ 2 The optical signal passes through and is output to the multiplexed communication transmission path 90.

[0053] Fig.11 FIG. 1 is a diagram showing a configuration example of an optical SW 10g that performs WDM transmission and downstream multicast. The optical SW 10g has Figure 5 The same distribution section 59. In addition, Fig. 9 and Fig.10 The light SW10f and Fig.11 The light SW10g shown may have Figure 6 The same monitoring circuit 65. The wavelength management control unit 25 can perform wavelength change processing similar to the above for the subscriber device 40 whose monitoring circuit 65 detects abnormality in the communication status.

[0054] Fig.12 This is a diagram showing a situation where the optical SW 10g performs WDM transmission and downstream multicast. Fig.12 The connection structure shown is Fig.11 The connection structure shown is different in that a WDM device 81 connected to a plurality of ports 11-1 is provided instead of the WDM device 80 connected to the plurality of ports 11-2 of the optical SW10g. In the WDM device 81, one or more subscriber devices 40 are connected to the opposite side of the port 11-1. The optical SW10g inputs optical signals of a plurality of wavelengths from other grounds from the port 11-2, and outputs them to the port 11-1 of the return transmission path connected to the distribution unit 59. The optical signals of a plurality of wavelengths are branched as they are by the power divider 72. The optical SW10d inputs the branched optical signals of a plurality of wavelengths from the plurality of ports 11-2, and outputs the input optical signals to any one of the ports 11-1 connected to the WDM device 81. The WDM device 81 filters the optical signals of a wavelength corresponding to the port 11-1 to which the optical signals are input from the input optical signals of a plurality of wavelengths, passes them, and outputs the optical signals that have passed through to the transmission path connected to the subscriber device 40.

[0055] Fig.13 FIG. 1 is a diagram showing a configuration example of an optical SW 10h that performs electrical processing on an optical signal. Fig.13 In, with Figure 3 The same parts as those of the light SW10b are denoted by the same reference numerals, and their description is omitted. Fig.13, the control unit 20 is omitted. The optical SW10h is different from the optical SW10a to 10g described above in that it also has a port 12-1 and a port 12-2. The ports 12-1 and 12-2 are connected to the electrical processing unit 84 via the transmission path 52. In addition, the ports connected to the electrical processing unit 84 via the transmission path 52 may also use the ports 11-1 and 11-2.

[0056] The optical SW 10h outputs the optical signal input from the subscriber device 40 from the port 11-2 or the port 12-1 according to the combination of the subscriber device 40 of the transmission source of the optical signal or the port 11-1 to which the optical signal is input and the wavelength, according to the control of the optical SW control section 26. In addition, the optical SW 10h outputs the output destination of the optical signal input from the port 11-2 from the port 11-1 or the port 12-1 according to the combination of the port 11-2 to which the optical signal is input and the wavelength, according to the control of the optical SW control section 26.

[0057] The optical SW10h outputs the optical signal from the port 12-1, thereby branching the optical signal to the electrical processing unit 84. The electrical processing unit 84 electrically terminates the branched optical signal, applies various electrical processing such as error correction and line aggregation, and then converts it into an optical signal and inputs it to the port 12-2 of the optical SW10h. The optical SW10h outputs the optical signal input from the electrical processing unit 84 from the port 11-1 or the port 11-2 according to the destination specified by the combination of the port 12-2 and the wavelength. In this way, the electrical processing unit 84 performs OE (electrical processing added)-O conversion (O represents light and E represents electricity). In addition, the electrical processing unit 84 may simply perform OEO conversion without performing electrical processing for function addition. When performing OEO conversion, the electrical processing unit 84 performs 3R reproduction (Re-amplification: amplification, Re-timing: timing reproduction, Re-shaping: waveform shaping) or performs 0 / 1 inversion to use the threshold effect, thereby reducing the optical waveform degradation associated with transmission. Note that the wavelength of the optical signal before conversion into the electrical signal and the wavelength of the optical signal after conversion from the electrical signal may be the same or different.

[0058] Furthermore, in a case where the port serving as the output destination of the optical SW is determined by a combination of a subscriber device that sends an optical signal and a wavelength, that is, where the wavelength is used as destination information, the destinations can be made different in the direction from port 11-1 to port 11-2 and in the direction from port 11-2 to port 11-1 via the electrical processing unit 84 even if the wavelength is the same.

[0059] The electrical processing unit 84 includes an O / E (optical / electrical) conversion unit 85, a processing execution unit 86, an E / O (electrical / optical) conversion unit 87, and a storage unit 88. The O / E conversion unit 85 converts the optical signal input from the optical SW10h into an electrical signal. The processing execution unit 86 includes a processor 861 and an accelerator 862. The processor 861 is, for example, a general-purpose processor such as a CPU (central processing unit). The accelerator 862 is, for example, a processor such as a GPU (Graphics Processing Unit). The processor 861 and the accelerator 862 read out and execute a program from the storage unit 88, thereby performing electrical signal processing on the electrical signal converted by the O / E conversion unit 85. The processing execution unit 86 can perform electrical signal processing of multiple functions. Examples of electrical signal processing are DSP (digital signal processing, Digital Signal Processing) for long-distance / high-speed access, mobile fronthaul processing, error correction, etc. The E / O converter 87 converts the electric signal into an optical signal of a wavelength specified by the optical SW controller 26, and outputs the optical signal to the optical SW 10h. The storage 88 stores a program for the processor 861 and the accelerator 862 to execute the function of processing the electric signal.

[0060] By making the processing execution unit 86 a device architecture based on a general-purpose processor, it is possible to add and change the electrical signal processing, and it is also possible to replace various functions other than the transmission function. In addition, the processing execution unit 86 performs DSP for long-distance / high-speed access, thereby eliminating the need for a dedicated LSI (Large-Scale Integration) for long-distance / high-speed access, thereby enabling flexible functional configuration corresponding to needs.

[0061] The optical SW 10h may be connected to a plurality of electrical processing units 84. In this case, the optical SW 10h has ports 12-1 and 12-2 connected to the electrical processing units 84. Each of the electrical processing units 84 may perform different electrical signal processing, or some or all of them may perform the same electrical processing.

[0062] The processing execution unit 86 and the storage unit 88 may also be implemented using hardware such as an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array).

[0063] Fig.141 is a diagram showing an example of connection using optical SW10h. Three subscriber devices 40 connected to optical SW10h are described as subscriber devices 40-1, 40-2, and 40-3. Subscriber devices 40-1, 40-2, and 40-3 are, for example, ONUs. A user 46-1 using subscriber device 40-1 is a user who performs long-distance or high-speed communication. One or more communication devices of user 46-1 are connected to subscriber device 40-1. Subscriber device 40-1 communicates with a device at a communication destination via long-distance line P1. Mobile base station 46-2 is connected to subscriber device 40-2. Fig.14 In the example, a plurality of subscriber devices 40-2 are connected to one transmission path 50-1 via a power splitter 55. The subscriber device 40-2 communicates with a device at a communication destination via a medium-distance line P2. The user 46-3 using the subscriber device 40-3 is a user performing medium-distance or medium-speed communication. One or more communication devices of the user 46-3 communicate with a device at a communication destination via the medium-distance line P3 via the subscriber device 40-3. The optical signals of the long-distance line P1, the medium-distance line P2, and the medium-distance line P3 are wavelength-division multiplexed and transmitted in a multiplexed communication transmission path 90 connected to the core NW (network). The electrical processing unit 84 has a DSP function for long-distance / high-speed access, a mobile fronthaul processing function, an error correction function, and the like.

[0064] use Fig.13 and Fig.14 The operation of the optical SW 10h will be described below. The optical SW 10h outputs the uplink optical signal sent by the subscriber device 40-1 to the electrical processing unit 84. The O / E conversion unit 85 of the electrical processing unit 84 converts the input optical signal into an electrical signal. The processing execution unit 86 performs DSP processing for long-distance / high-speed access on the converted electrical signal. The E / O conversion unit 87 converts the DSP-processed electrical signal into an optical signal and outputs it to the optical SW 10h. The wavelength after conversion may be the same as or different from the wavelength when input to the electrical processing unit 84. The optical SW 10h outputs the optical signal input from the electrical processing unit 84 from the port 11-2 to the multiplexed communication transmission path 90.

[0065] In addition, the optical SW10h inputs a downstream optical signal transmitted in the multiplexed communication transmission path 90 and addressed to the subscriber device 40-1. The optical SW10h outputs the input downstream optical signal from the port 12-1 to the electrical processing unit 84 according to the combination of the input port 51-2 and the wavelength. The O / E conversion unit 85 of the electrical processing unit 84 converts the input optical signal into an electrical signal, and the processing execution unit 86 performs DSP processing for long-distance / high-speed access on the converted electrical signal. The E / O conversion unit 87 converts the DSP-processed electrical signal into an optical signal and outputs it to the optical SW10h. The wavelength of the optical signal after conversion may be the same as or different from the wavelength when it is input to the electrical processing unit 84. The optical SW10h outputs the optical signal input from the electrical processing unit 84 to the port 11-1 connected to the subscriber device 40-1.

[0066] The same processing as that of the optical signal transmitted and received by the subscriber device 40-1 is also performed on the optical signal transmitted and received by the subscriber device 40-2. However, the processing execution unit 86 performs mobile fronthaul processing on the optical signal transmitted and received by the subscriber device 40-2. The processing execution unit 86 determines the signal processing to be performed on the electrical signal based on any information included in the electrical signal.

[0067] On the other hand, the optical SW 10h outputs the upstream optical signal input from the subscriber device 40-3 from the port 11-2 to the multiplexed communication transmission path 90. In addition, the optical SW 10h inputs the downstream optical signal transmitted in the multiplexed communication transmission path 90 to the subscriber device 40-3, and outputs it to the port 11-1 connected to the subscriber device 40-3 according to the combination of the port 11-2 to which the optical signal is input and the wavelength.

[0068] Next, use Figure 15 to Figure 23 To illustrate the access topology to the optical SW.

[0069] Fig.15 This is a diagram showing a PDS (Passive Double Star) type access topology using time division multiplexing. As the optical SW1001, the above-mentioned optical SW10a to 10h can be used. The optical SW1001 has ports 11-1-1 to 11-1-P and ports 11-2-1 to 11-2-Q. The transmission path 50-1 connected to the port 11-1-p (p is an integer greater than 1 and less than P) is also recorded as the transmission path 50-1-p, and the transmission path 50-2 connected to the port 11-2-q (q is an integer greater than 1 and less than Q) is also recorded as the transmission path 50-2-q. Fig.15 In the example, the port 11-2-q is connected to the ground #q via the transmission path 50-2-q.

[0070] A power splitter 56 is provided in the transmission path 50-1-p. Np (Np is an integer greater than or equal to 2) subscriber devices 40-p are connected to the power splitter 56 in a star configuration. The Np subscriber devices 40-p are described as subscriber devices 40-p-1 to 40-p-Np, and the transmission path 50-1-p between the subscriber device 40-p-np (np is an integer greater than or equal to 1 and less than or equal to Np) and the power splitter 56 is described as 50-1-p-np. The subscriber devices 40-p-1 to 40-p-Np use the same wavelength by time division multiplexing. The wavelength used in the upstream optical signal is different from the wavelength used in the downstream optical signal.

[0071] The optical SW 1001 receives the wavelengths λ of the time-division multiplexed signals sent to the subscriber devices 40-p-1 to 40-p-Np from the port 11-2-q. 1 The optical SW1001 receives the input downstream optical signal from port 11-2-q and wavelength λ 1 The power splitter 56 inputs the time-division multiplexed downlink optical signal from the transmission path 50-1-p, branches the input optical signal and outputs it to the transmission paths 50-1-p-1 to 50-1-p-Np. The subscriber devices 40-p-1 to 40-p-Np receive the time-division multiplexed optical signal and select the downlink optical signal to be sent to the subscriber device from the received optical signal.

[0072] In addition, the subscriber devices 40-p-1 to 40-p-Np transmit the same wavelength λ by TDMA (Time Division Multiple Access). 2 The power divider 56 inputs the wavelength λ from the transmission paths 50-1-p-1 to 50-1-p-Np respectively. 2 The optical SW 1001 transmits the uplink optical signal to the transmission path 50-1-p by time division multiplexing the input optical signal. 2 The port 11-2-q corresponding to the combination outputs the time-division-multiplexed upstream optical signal.

[0073] Furthermore, the PDS type access topology can be applied to any one or more of the transmission paths 50 - 1 - 1 to 50 - 1 -P.

[0074] Fig.161 is a diagram showing an access topology of a PDS type using wavelength division multiplexing. As the optical SW1002, the above-mentioned optical SW10a~10h can be used. The optical SW1002 is connected to one or more WDM devices 81. The WDM device 81 multiplexes the downstream optical signals of different wavelengths output from each of the multiple ports 11-1, and outputs them to the multiplexed communication transmission path 91. In addition, the WDM device 81 demultiplexes the upstream wavelength division multiplexed optical signal received via the multiplexed communication transmission path 91, and inputs the demultiplexed optical signals to different ports 11-1 respectively. A power splitter 56 is provided in the multiplexed communication transmission path 91. N (N is an integer greater than or equal to 2) subscriber devices 40 are connected to the power splitter 56 in a star shape. The subscriber devices 40 and the power splitter 56 are connected via a transmission path 92. The multiple subscriber devices 40 connected to the power splitter 56 respectively transmit and receive optical signals of different wavelengths.

[0075] exist Fig.16 Ports 11 - 1 -p to 11 - 1 -(p+N) of the optical SW 1002 are connected to the WDM device 81 via the transmission path 50 - 1 (p and N are integers greater than 1, and p+N is an integer less than P). In addition, subscriber devices 40 - p to 40 -(p+N) are connected to the power splitter 56 .

[0076] Optical SW1002 inputs wavelength λ from port 11-2-(q+n) 1(q+n) A downstream optical signal sent to the subscriber device 40-(p+n) (q is an integer greater than or equal to 1, and n is an integer greater than or equal to 0 and less than or equal to N). Fig.16 This is an example of the case where q=1. The light SW1002 is directed to the port 11-2-(q+n) and the wavelength λ 1(1+n) The output destination port 11-1-(p+n) corresponding to the combination of is routed to the wavelength λ input from the port 11-2-(q+n) 1(1+n) Thus, the optical SW 1002 routes the wavelength λ input from the port 11-2-1 to the port 11-1-p. 11 The downstream optical signal is routed to port 11-1-(p+1) with wavelength λ input from port 11-2-2. 12 The downstream optical signal.

[0077] The WDM device 81 performs a multiplication of wavelengths λ output from each of the ports 11-1-p to 11-1-(p+N). 11 ~λ 1NThe power splitter 56 inputs the wavelength-division-multiplexed downstream optical signal from the multiplexed communication transmission path 91, branches the input downstream optical signal as it is, and outputs it to the transmission path 92 between each of the subscriber devices 40-p to 40-(p+N). The subscriber devices 40-p to 40-(p+N) receive the wavelength-division-multiplexed downstream optical signal, and select the downstream optical signal of the wavelength used by the device from the received optical signal.

[0078] In addition, the subscriber device 40-(p+n) transmits wavelength λ 2(1+n) The power splitter 56 receives an uplink optical signal from each of the subscriber devices 40-p to 40-(p+N) via the transmission path 92, and divides the input wavelength λ into 21 ~λ 2(1+N) Each of the uplink optical signals is wavelength-division multiplexed and output to the multiplexed communication transmission path 91. The WDM device 81 inputs the wavelength-division multiplexed uplink optical signal from the multiplexed communication transmission path 91 and performs wavelength separation. 2(1+n) The uplink optical signals are input to ports 11-1-(p+n) respectively. The optical SW 1002 receives the optical signals from ports 11-1-(p+n) and wavelength λ 2(1+n) The output wavelength λ of the output destination port 11-2-(q+n) corresponding to the combination of 2(1+n) Thus, the wavelength λ transmitted by the subscriber device 40-p is 21 The upstream optical signal is input from the port 11-1-p and output from the port 11-2-1. 22 The uplink optical signal is input from port 11-1-(p+1) and output from port 11-2-2. Fig.17 As shown, a configuration may be adopted in which the WDM device is placed at a subsequent stage of the optical SW.

[0079] Fig.17 1 is a diagram showing a PDS type access topology in which wavelength division multiplexing is used and a WDM device is placed at the rear stage of an optical SW. As the optical SW 1003, the above-mentioned optical SWs 10a to 10h can be used. Port 11-2-q (q is an integer greater than 1 and less than Q) of the optical SW 1003 is connected to the WDM device 97 via a transmission path 50-2-q. The WDM device 97 is connected to ground #n (n is an integer greater than 1 and less than N) via a transmission path 50-2-qn. A power splitter 56 is provided in the transmission path 50-1-p connected to the port 11-1-p of the optical SW 1003. N subscriber devices 40-p-1 to 40-pN are connected to the power splitter 56 in a star configuration.

[0080] The WDM device 97 receives the wavelength λ transmitted from the ground #n from the transmission path 50-2-qn. 1n The WDM device 97 receives the λ input from each of the pairs #1 to #N. 11 ~λ 1N The wavelength division multiplexed signal of the downstream optical signal is input to the optical SW1003. The optical SW1003 outputs the downstream wavelength division multiplexed signal input from the port 11-2-q from the port 11-1-p of the output destination. The power splitter 56 branches the wavelength division multiplexed signal input from the transmission path 50-1-p and outputs it to the transmission paths 50-1-p-1 to 50-1-pN. The subscriber devices 40-p-1 to 40-pN receive the wavelength division multiplexed signal and select the downstream optical signal sent to the device from the received optical signal. Thus, the subscriber device 40-pn receives the wavelength λ from the ground #n. 1n light signal.

[0081] In addition, the subscriber device 40-pn transmits a wavelength λ 2n The power splitter 56 receives the wavelength λ from each of the subscriber devices 40-p-1 to 40-pN via the transmission paths 50-1-p-1 to 50-1-pN. 21 ~λ 2N The power divider 56 divides the wavelength λ 21 ~λ 2N The wavelength division multiplexed signal of the uplink optical signal is output to the transmission path 50-1-p. The optical SW 1003 is input from the port 11-1-p with a wavelength of λ 21 ~λ 2N The optical SW 1003 outputs the upstream wavelength-division-multiplexed signal from the output destination port 11-2-q to the transmission path 50-2-q. The WDM device 97 inputs the wavelength-division-multiplexed upstream optical signal from the transmission path 50-2-q and performs wavelength separation. The WDM device 97 separates the wavelength λ 2n The uplink optical signal is output to the transmission path 50-2-n connected to the ground #n. 2n The optical signal is sent to ground #n.

[0082] Fig.18 This is a diagram showing a bus-type access topology using time division multiplexing. As the optical SW 1004, the above-mentioned optical SWs 10a to 10h can be used. Fig.18 The access topology shown is similar to Fig.15The difference of the access topology shown is that a plurality of subscriber devices 40-p-1 to 40-p-Np are connected to a transmission path 50-1-p in a bus type. One or more power splitters 55 are provided in the transmission path 50-1-p. The power splitter 55 to which the subscriber device 40-pn (n is an integer greater than 1 and less than Np-1) is connected is referred to as a power splitter 55-n.

[0083] Subscriber devices 40-p-1 to 40-p-Np use the same wavelength by time division multiplexing. The wavelength used in the uplink optical signal is different from the wavelength used in the downlink optical signal. Transmission path 50-2-1 connected to ground #1 transmits the time-division multiplexed wavelength λ to each of subscriber devices 40-p-1 to 40-p-Np. 1 The optical SW 1004 inputs the time-division multiplexed wavelength λ transmitted in the transmission path 50-2-1 from the port 11-2-1. 1 The optical SW1004 is connected to port 11-2-1 (or to ground #1) and wavelength λ 1 The optical SW 1004 routes the input downstream optical signal to the output destination port 11-1-p corresponding to the combination. The optical SW 1004 will be time-division multiplexed with the wavelength λ 1 The downstream optical signal is output from the port 11-1-p to the transmission path 50-1-p. The power splitter 55-n branches the time-division multiplexed downstream optical signal from the transmission path 50-1-p, and outputs the branched downstream optical signal to the subscriber device 40-pn. The subscriber devices 40-p-1 to 40-p-Np receive the time-division multiplexed downstream optical signal, and select the downstream optical signal to be sent to the subscriber device from the received downstream optical signal.

[0084] In addition, the subscriber devices 40-p-1 to 40-p-Np transmit the same wavelength λ by TDMA (Time Division Multiple Access). 2 Each power splitter 55-n receives the wavelength λ input from the subscriber device 40-pn. 2 The uplink optical signal transmitted in the transmission path 50-1-p is time-division multiplexed with the uplink optical signal transmitted in the transmission path 50-1-p. The optical SW 1004 inputs the time-division multiplexed uplink optical signal from the port 11-1-p and transmits the time-division multiplexed uplink optical signal to the port 11-1-p and the wavelength λ 2 The data is routed to the port 11-2-1 of the output destination corresponding to the combination of and output to the transmission path 50-2-1 connected to the ground #1.

[0085] Furthermore, a bus-type access topology can be applied to any one or more of the transmission paths 50 - 1 - 1 to 50 - 1 -P.

[0086] Fig.19This is a diagram showing a bus-type access topology using wavelength division multiplexing. As the optical SW 1005, the above-mentioned optical SWs 10a to 10h can be used. Fig.19 The access topology shown is similar to Fig.16 The difference of the access topology shown is that a plurality of subscriber devices 40-p to 40-(p+N) are connected to a multiplexed communication transmission path 91 in a bus type. The subscriber devices 40-p to 40-(p+N) respectively transmit and receive optical signals of different wavelengths. One or more power splitters 55 are provided in the multiplexed communication transmission path 91. The power splitter 55 to which the subscriber device 40-(p+n) (n is an integer greater than or equal to 0 and less than or equal to N-1, and N is an integer greater than or equal to 1) is connected is referred to as a power splitter 55-(p+n).

[0087] Light SW1005 with Fig.16 Similarly, the light SW1002 shown in FIG. 11 is input from port 11-2-(q+n) with a wavelength of λ 1(1+n) A downstream optical signal sent to the subscriber device 40-(p+n) (q is an integer greater than or equal to 1, and n is an integer greater than or equal to 0 and less than or equal to N). Fig.19 This is an example of the case where q=1. The light SW1005 is directed to the port 11-2-(q+n) and the wavelength λ 1(1+n) The output destination port 11-1-(p+n) corresponding to the combination of the wavelength λ input from the port 11-2-(q+n) is routed 1(1+n) The downstream optical signal.

[0088] The WDM device 81 performs a multiplication of wavelengths λ output from each of the ports 11-1-p to 11-1-(p+N). 11 ~λ 1N The downstream optical signals are multiplexed and output to the multiplexed communication transmission path 91. The power splitter 55-(p+n) branches the wavelength-division-multiplexed downstream optical signals from the multiplexed communication transmission path 91, and outputs the branched downstream optical signals to the subscriber device 40-(p+n). The subscriber devices 40-p to 40-(p+N) receive the wavelength-division-multiplexed downstream optical signals, and select the downstream optical signals sent to the subscriber devices from the received downstream optical signals.

[0089] In addition, the subscriber device 40-(p+n) transmits wavelength λ 2(1+n) Each power splitter 55-(p+n) divides the wavelength λ input from the subscriber device 40-(p+n) into 2(1+n) The uplink optical signal and the uplink wavelength λ transmitted in the multiplexed communication transmission path 91 2(2+n) ~λ 2N The WDM device 81 inputs the wavelength-division-multiplexed uplink optical signal from the multiplexed communication transmission path 91 and separates it into wavelengths λ 21 ~λ2N The WDM device 81 converts the wavelength λ 2(1+n) The uplink optical signal is input to port 11-1-(p+n). Fig.16 Similarly, the light SW1002 shown in FIG. 1 is transmitted from the input port 11-1-(p+n) and the wavelength λ 2(1+n) The output wavelength λ of the output destination port 11-2-(q+n) corresponding to the combination of 2(1+n) Thus, the wavelength λ transmitted by the subscriber device 40-p is 21 The upstream optical signal is input from the port 11-1-p and output from the port 11-2-1. 22 The uplink optical signal is input from port 11-1-(p+1) and output from port 11-2-2. Fig. 20 As shown, a configuration may be adopted in which the WDM device is placed at a subsequent stage of the optical SW.

[0090] Fig. 20 This is a diagram showing a bus-type access topology using wavelength division multiplexing and placing a WDM device after an optical SW. As the optical SW 1006, the optical SWs 10a to 10h described above can be used. Fig. 20 In, with Fig.17 The same parts are marked with the same reference numerals. Port 11-2-q (q is an integer greater than 1 and less than Q) of optical SW1006 is connected to WDM device 97 via transmission path 50-2-q. WDM device 97 is connected to ground #n (n is an integer greater than 1 and less than N, and N is an integer greater than 2) via transmission path 50-2-qn. One or more power splitters 55 are provided in transmission path 50-1-p connected to port 11-1-p (p is an integer greater than 1 and less than P) of optical SW1006. Power splitter 55 to which subscriber device 40-pn is connected is referred to as power splitter 55-n.

[0091] The WDM device 97 receives the wavelength λ transmitted from the ground #n from the transmission path 50-2-qn. 1n The WDM device 97 transmits the wavelength λ input from each of the base station #1 to base station #N to the downstream optical signal sent to the subscriber device 40-pn. 11 ~λ 1NThe wavelength division multiplexed signal obtained by multiplexing the downstream optical signals is input to optical switch 1006. Optical switch 1006 outputs the downstream wavelength division multiplexed signal input from port 11-2-q from output destination port 11-1-p. Power splitter 55-n branches the downstream wavelength division multiplexed signal from transmission path 50-1-p and outputs the branched downstream wavelength division multiplexed signal to subscriber device 40-p-n. Subscriber devices 40-p-1 to 40-p-N select the downstream optical signal addressed to their own devices from the received downstream wavelength division multiplexed signal. Thus, subscriber device 40-p-n receives the optical signal with wavelength λ 1n from ground #n.

[0092] In addition, subscriber device 40-p-n transmits an upstream optical signal with wavelength λ 2n . Each power splitter 55-n multiplexes the upstream optical signal with wavelength λ 2n input from subscriber device 40-p-n with the upstream optical signal transmitted in transmission path 50-1-p. Optical switch 1006 inputs the wavelength division multiplexed signal obtained by multiplexing the upstream optical signals with wavelengths λ 21 to λ 2N from port 11-1-p. Optical switch 1006 outputs the upstream wavelength division multiplexed signal from output destination port 11-2-q to transmission path 50-2-q. WDM device 97 inputs the wavelength division multiplexed signal from transmission path 50-2-q and performs wavelength demultiplexing. WDM device 97 outputs the upstream optical signal with wavelength λ 2n to transmission path 50-2-q-n connected to ground #n. Thus, the optical signal with wavelength λ 2n transmitted by subscriber device 40-p-n is sent to ground #n.

[0093] Fig.21 FIG. shows a loop-type access topology. As optical switch 1007, the above-described optical switches 10a to 10h can be used. A part of ports 11-1-p1 to 11-1-pN (p1 < pN, p1 is an integer of 1 or more, and pN is an integer of P or less) of optical switch 1007 are connected to WDM access ring network 31 that transmits optical signals of multiple wavelengths. Optical signals of several wavelengths used in WDM access ring network 31 are transmitted to subscriber device 40 or the upper NW at the communication destination via optical switch 1007. In the topology shown in Fig.21 , a WDM multiplexer / demultiplexer is not used, and subscriber devices 40 facing each other are connected by two transmission paths and communicate.

[0094] WDM access ring network 31 is a network in which R add / drop nodes 32 are connected by transmission path 53. Fig.21This is an example of R=4. R add / drop nodes 32 are described as add / drop nodes 32-1 to 32-R, and the transmission path 53 between the add / drop node 32-r (r is an integer greater than 1 and less than R) and the add / drop node 32-(r+1) is described as a transmission path 53-r. However, the add / drop node 32-(R+1) is regarded as the add / drop node 32-1. The add / drop node 32-1 is connected to the port 11-1-pn (pn is an integer greater than p1 and less than pN) of the optical SW 1007 via the transmission path 50-1-pn.

[0095] The add / drop node 32 includes a wavelength splitter 33, an optical SW 34, and a wavelength combiner 35. The wavelength splitter 33 of the add / drop node 32-r (r is an integer greater than or equal to 2 and less than or equal to R) splits the wavelength division multiplexed optical signal input from the transmission path 53-(r-1), and outputs the optical signal obtained by the wavelength splitting to the optical SW 34. The optical SW 34 is connected to one or more subscriber devices 40. In this figure, only one subscriber device 40 connected to the optical SW 34 is shown. The optical SW 34 splits the optical signal of the wavelength corresponding to the node among the optical signals input from the wavelength splitter 33. The optical receiver 43 of the subscriber device 40 receives the optical signal split by the optical SW 34. In addition, the optical SW 34 inputs the optical signal transmitted by the optical transmitter 42 of the subscriber device 40, and outputs the input optical signal and the unsplit optical signal to the wavelength combiner 35. The wavelength combiner 35 of the add / drop node 32-r multiplexes the optical signal input from the optical SW 34, and outputs it to the transmission path 53-r. Furthermore, the optical SW 34 of the add / drop node 32-1 demultiplexes the optical signal of the wavelength corresponding to the node, among the optical signals demultiplexed by the demultiplexing section 33, and inputs the optical signals of each wavelength to the transmission path 50-1-pn. 1 (pn 1 =1, 3, 5, ..., p(N-1)). Port 11-1-pn of optical SW 1007 1 From the transmission path 50-1-pn 1 The optical signal dropped by the add / drop node 32-1 is input. 2 Input optical SW1007 from port 11-1-pn 2 (pn 2 =2, 4, 6, ..., pN) output optical signals, and output the input optical signals and the un-branched optical signals to the combining unit 35.

[0096] Thus, ONU#1, which is a subscriber device 40 connected to the add / drop node 32-4 of the WDM access ring network 31, and ONU#2, which is a subscriber device 40 connected to the ports 11-2-1 and 11-2-2 of the optical SW 1007, communicate as follows.

[0097] ONU#1 sends the wavelength λ 1 The optical signal of the add / drop node 32-4 is sent to the add / drop node 32-4. The wavelength multiplexing unit 35 of the add / drop node 32-4 combines the wavelength λ input to the optical SW 34 1 The optical signal of the add / drop node 32-1 is combined with the optical signal not branched by the optical SW 34, and output to the add / drop node 32-1. The optical SW 34 of the add / drop node 32-1 combines the wavelength λ after the wavelength branching section 33 has branched the wavelength λ. 1 The optical signal of the add / drop node 32-1 is demultiplexed and the undemultiplexed optical signal is output to the multiplexing unit 35. The port 11-1-p1 of the optical SW 1007 receives the wavelength λ demultiplexed by the add / drop node 32-1 from the transmission path 50-1-p1. 1 The optical SW 1007 outputs the wavelength λ input from port 11-1-p1 from port 11-2-1. 1 The optical receiver 43 of ONU#2 receives the wavelength λ transmitted in the transmission path 50-2-1. 1 light signal.

[0098] The optical transmitter 42 of ONU#2 transmits a wavelength λ 2 The optical SW 1007 receives the optical signal transmitted by ONU #2 from the transmission path 50-2-2 at port 11-2-2. The optical SW 1007 outputs the wavelength λ received from port 11-2-2 from port 11-1-p2. 2 The optical SW 34 of the add / drop node 32-1 inputs the wavelength λ output by the optical SW 1007 from the transmission path 50-1-p2. 2 The input optical signal and the un-branched optical signal are output to the combining unit 35. Wavelength λ 2 The optical signal of the add / drop node 32-4 is input to the add / drop node 32-4 via the add / drop nodes 32-2 and 32-3. 2 The optical receiver 43 of ONU#1 receives the wavelength λ demultiplexed by the add / drop node 32-4. 2 light signal.

[0099] Fig. 22 This is a diagram showing a loop-type access topology using a WDM multiplexer / demultiplexer. As the optical SW 1008, the above-mentioned optical SWs 10a to 10h can be used. Fig. 22 The access topology shown is similar to Fig.21 The access topology shown is different in that the optical SW 1008 and the WDM access ring network 31 are connected via a WDM device 81 and a WDM device 89 .

[0100] The add / drop node 32-1 of the WDM access ring network 31 and the WDM device 89 are connected via transmission paths 93-1 to 93-N (N is an integer greater than or equal to 2). 1 (n 1 =1, 3, 5, ..., N-1) receiving wavelength λ n1 The WDM device 89 multiplexes the received upstream optical signal and outputs the multiplexed signal to the multiplexed communication transmission path 91. In addition, the WDM device 89 demultiplexes the downstream wavelength division multiplexed optical signal received via the multiplexed communication transmission path 91 and outputs the demultiplexed wavelength λ to the multiplexed optical signal. n2 The downlink optical signal is input to the transmission path 93-n 2 (n 2 =2, 4, 6, …, N).

[0101] The WDM device 81 demultiplexes the upstream wavelength-division-multiplexed optical signal received via the multiplexed communication transmission path 91, and converts the demultiplexed wavelength λ n1 The uplink optical signals are input to ports 11-1-n respectively. 1 The WDM device 81 receives the data from the ports 11-1-pn 2 The wavelength λ of each output n2 The received downstream optical signal is multiplexed and output to the multiplexed communication transmission path 91.

[0102] Thus, ONU#1, which is a subscriber device 40 connected to the add / drop node 32-4 of the WDM access ring network 31, and ONU#2, which is a subscriber device 40 connected to the port 11-2-1 and the port 11-2-2 of the optical SW 1008, communicate as follows. Here, the case where N=18 is used as an example for explanation.

[0103] ONU#1 sends the wavelength λ 1 The upstream optical signal of wavelength λ is sent to the add / drop node 32-4. 3 , 5 The uplink optical signal is sent to the add / drop node 32-4. The optical SW 34 of the add / drop node 32-4 inputs the wavelength λ 1 , 3 , 5 The wavelength λ input to the optical SW 34 is converted by the wavelength combining unit 35 of the add / drop node 32-4. 1 , 3 , 5 The optical signal of the add / drop node 32-1 is combined with the optical signal not branched by the optical SW 34, and output to the add / drop node 32-1. The optical SW 34 of the add / drop node 32-1 combines the wavelength λ branched by the branching unit 33. 1, 3 , 5 , …λ 17 The WDM device 89 branches the optical signal of the transmission path 93-1, 93-3, 93-5, ..., 93-17, and outputs the unbranched optical signal to the multiplexing unit 35. 1 , 3 , 5 , …λ 17 The multiplexed signal after multiplexing the uplink optical signal is output to the multiplexed communication transmission path 91.

[0104] The WDM device 81 inputs the wavelength-division-multiplexed upstream optical signal from the multiplexed communication transmission path 91 and performs wavelength separation. 1 ,λ3,λ5,…λ 17 The uplink optical signals are input to ports 11-1-p1, 11-1-p3, 11-1-p5, ..., 11-1-p17 of the optical SW 1008. The optical SW 1008 outputs the wavelength λ from the output destination port 11-2-1. 1 The optical receiver 43 of ONU#2 receives the wavelength λ transmitted in the transmission path 50-2-1. 1 light signal.

[0105] The optical transmitter 42 of ONU#2 transmits a wavelength λ 2 The optical SW 1008 receives the optical signal transmitted by ONU #2 from the transmission path 50-2-2 at port 11-2-2. The optical SW 1008 outputs the wavelength λ input from port 11-2-2 from port 11-1-p2. 2 Furthermore, the optical SW 1008 outputs the wavelength λ input from each of the ports 11-2-4, 11-2-6, ..., 11-2-18 from the ports 11-1-p4, 11-2-p6, ..., 11-2-p18. 4 , 6 , …, λ 18 The downstream optical signal.

[0106] The WDM device 81 converts the wavelength λ output from each of the ports 11-1-p2, 11-1-p4, 11-1-p6, ..., 11-1-p18 into 2 , 4 , 6 , …, λ 18 The wavelength division multiplexed signal after multiplexing the downstream optical signal is output to the multiplexed communication transmission path 91. The WDM device 89 separates the wavelength division multiplexed signal transmitted in the multiplexed communication transmission path 91, and transmits the wavelength λ obtained by separation to the multiplexed communication transmission path 91. 2 ,4 , 6 , …, λ 18 The optical SW 34 of the add / drop node 32-1 inputs the wavelength λ output by the WDM device 89 from the transmission paths 93-2, 93-4, 93-6, ..., 93-18. 2 , 4 , 6 , …, λ 18 The multiplexing unit 35 multiplexes the optical signals input from the optical SW 34 and outputs the input optical signals and the un-divided optical signals to the multiplexing unit 35. The multiplexing unit 35 multiplexes the optical signals input from the optical SW 34 and outputs the multiplexed optical signals to the transmission path 53-1.

[0107] The demultiplexer 33 of the add / drop node 32-2 demultiplexes the optical signal input from the transmission path 53-1 and outputs the demultiplexed optical signal to the optical SW 34. The optical SW 34 demultiplexes the optical signal corresponding to the wavelength λ of the node. 14 , 16 , 18 The optical signal is branched. Wavelength λ 14 , 16 , 18 The optical signal of is transmitted to the optical receiver 43 of the subscriber device 40 corresponding to each wavelength. In addition, the optical SW 34 of the add / drop node 32-2 inputs the wavelength λ transmitted by the optical transmitter 42 of each subscriber device 40. 13 , 15 , 17 The optical signal is multiplexed, and the input optical signal and the un-divided optical signal are output to the multiplexing unit 35. The multiplexing unit 35 multiplexes the optical signal input from the optical SW 34, and outputs it to the transmission path 53-2.

[0108] The add / drop node 32-3 also operates in the same manner as the add / drop node 32-2. However, the optical SW 34 of the add / drop node 32-3 is for the wavelength λ corresponding to the node itself. 8 , 10 , 12 The optical signal is branched and the input wavelength λ 7 , 9 , 11 The wavelength division unit 33 of the add / drop node 32-4 divides the wavelength division multiplexed optical signal input from the transmission path 53-3 and outputs it to the optical SW 34. The optical SW 34 of the add / drop node 32-4 divides the wavelength division multiplexed optical signal corresponding to the node λ 2 , 4 , 6 The optical receiver 43 of ONU#1 receives the wavelength λ demultiplexed by the optical SW 34 of the add / drop node 32-4. 2 light signal.

[0109] Fig.23 This is a diagram showing an access topology in which a loop is formed in two access planes. As optical SW1009a and optical SW1009b, the above-mentioned optical SW10a to 10h can be used. Optical SW1009a and optical SW1009b are collectively recorded as optical SW1009. Two ports 11-1 of optical SW1009 are connected to both ends of a transmission path 54. One or more power dividers 57 are connected to the transmission path 54. The power divider 57 is connected to the optical transmitter 42 of one or more subscriber devices 40 via the combiner 82 and the optical SW95, and is connected to the optical receiver 43 of one or more subscriber devices 40 via the demultiplexer 83 and the optical SW96. Each subscriber device 40 transmits and receives optical signals of different wavelengths.

[0110] The transmission path 54 connected to the optical SW 1009a is recorded as a transmission path 54a, and the two ports 11-1 connected to the transmission path 54a are recorded as ports 11a-1-p1 and 11a-1-p2. The transmission path 54 connected to the optical SW 1009b is recorded as a transmission path 54b, and the two ports 11-1 connected to the transmission path 54b are recorded as ports 11b-1-p1 and 11b-1-p2. The N (N is an integer greater than 1) power dividers 57 connected to the transmission path 54a are recorded as power dividers 57a-1 to 57a-N, and the M (M is an integer greater than 1) power dividers 57 connected to the transmission path 54b are recorded as power dividers 57b-1 to 57b-M. The combiner 82 and the splitter 83 connected to the power splitter 57a-n (n is an integer greater than 1 and less than N) are recorded as the combiner 82a-n and the splitter 83a-n, respectively, and the combiner 82 and the splitter 83 connected to the power splitter 57b-m (m is an integer greater than 1 and less than M) are recorded as the combiner 82b-m and the splitter 83b-m, respectively. The light SW95 connected to the combiner 82a-n is recorded as the light SW95a-n, and the light SW96 connected to the splitter 83a-n is recorded as the light SW96a-n. The light SW95 connected to the combiner 82b-m is recorded as the light SW95b-m, and the light SW96 connected to the splitter 83b-m is recorded as the light SW96b-m.

[0111] The optical SW1009a and the optical SW1009b are connected via the transmission path 54c and the transmission path 54d. The port 11-2 of the optical SW1009a connected to the transmission path 54c is recorded as the port 11a-2-q1, and the port 11-2 of the optical SW1009a connected to the transmission path 54d is recorded as the port 11a-2-q2. In addition, the port 11-2 of the optical SW1009b connected to the transmission path 54c is recorded as the port 11b-2-q1, and the port 11-2 of the optical SW1009b connected to the transmission path 54d is recorded as the port 11b-2-q2.

[0112] In the above structure, the optical SW 95b-m outputs the optical signals of different wavelengths transmitted by the optical transmitter 42 of each subscriber device 40 to the ports corresponding to the wavelengths of the combiner 82b-m. The combiner 82b-m receives the optical signals of different wavelengths transmitted by the optical transmitter 42 of each subscriber device 40 via the optical SW 95b-m, and outputs a wavelength division multiplexed optical signal after multiplexing the received optical signals. The power divider 57b-m multiplexes the wavelength division multiplexed optical signal output by the combiner 82b-m with the wavelength division multiplexed optical signal transmitted in the transmission path 54b in the direction from the port 11b-1-p2 to the port 11b-1-p1, and outputs the multiplexed optical signal.

[0113] Port 11b-1-p1 of optical SW1009b inputs a wavelength division multiplexed optical signal from transmission path 54b, and outputs it from port 11b-2-q1. Port 11a-2-q1 of optical SW1009a inputs a wavelength division multiplexed optical signal output from port 11b-2-q1 of optical SW1009b from transmission path 54c. Optical SW1009a outputs the wavelength division multiplexed optical signal input from port 11a-2-q1 from port 11a-1-p1 to transmission path 54a.

[0114] The power splitter 57a-n branches the wavelength division multiplexed optical signal transmitted in the transmission path 54a in the direction from the port 11a-1-p1 to the port 11a-1-p2, and outputs the branched wavelength division multiplexed optical signal to the splitter 83a-n. The splitter 83a-n splits the wavelength division multiplexed optical signal received from the power splitter 57a-n, and outputs the split optical signal from the port corresponding to the wavelength to the optical SW 96a-n. The optical SW 96a-n outputs the optical signal of each wavelength input from the splitter 83a-n to the optical receiver 43 of the subscriber device 40 that receives the optical signal of the wavelength.

[0115] On the other hand, the optical SWs 95a-n output the optical signals of different wavelengths transmitted by the optical transmitters 42 of the subscriber devices 40 to the ports corresponding to the wavelengths of the combiners 82a-n. The combiners 82a-n receive the optical signals of different wavelengths transmitted by the optical transmitters 42 of the subscriber devices 40 via the optical SWs 95a-n, and output the wavelength-division-multiplexed optical signals obtained by multiplexing the received optical signals. The power dividers 57a-n multiplex the wavelength-division-multiplexed optical signals output by the combiners 82a-n with the wavelength-division-multiplexed optical signals transmitted in the transmission path 54a in the direction from the port 11a-1-p1 to the port 11a-1-p2, and output them.

[0116] Port 11a-1-p2 of optical SW1009a inputs a wavelength division multiplexed optical signal from transmission path 54a, and outputs it from port 11a-2-q2. Port 11b-2-q2 of optical SW1009b inputs a wavelength division multiplexed optical signal output from port 11a-2-q2 of optical SW1009a from transmission path 54d. Optical SW1009b outputs the wavelength division multiplexed optical signal input from port 11b-2-q2 from port 11b-1-p2 to transmission path 54b.

[0117] The power splitter 57b-m branches the wavelength-division-multiplexed optical signal transmitted in the transmission path 54b in the direction from the port 11b-1-p2 to the port 11b-1-p1, and outputs the branched wavelength-division-multiplexed optical signal to the splitter 83b-m. The splitter 83b-m splits the wavelength-division-multiplexed optical signal received from the power splitter 57b-m, and outputs the split optical signal from the port corresponding to the wavelength to the optical SW 96b-m. The optical SW 96b-m outputs the optical signal of each wavelength input from the splitter 83b-m to the optical receiver 43 of the subscriber device 40 that receives the optical signal of the wavelength.

[0118] Furthermore, in Fig.23 In FIG. 1 , the optical signal is shown to be transmitted in a counterclockwise direction, but it can also be transmitted in a clockwise direction, and the two left and right cores can be grouped together for redundancy.

[0119] Next, the connection structure when the number of user connections increases will be described. Fig.24 : is a diagram showing an example of the scalability required of the optical SW. Fig.24 , N (N is an integer greater than or equal to 1) lights SW1010-1 to 1010-N are shown. As the lights SW1010-1 to SW1010-N, the above-mentioned lights SW10a to 10h can be used. Fig.24, an example of N=4 is shown. In the figure, ONU#np as a subscriber device 40 is connected to port 11-1-p of optical SW1010-n (n is an integer greater than 1 and less than N). Port 11-2-q of optical SW1010-n is connected to an uplink. The uplink is a transmission path 50-2 connected to an upper network.

[0120] When the number of users is large and the number of ONUs increases, sometimes the optical SW 1010 will exceed the scale that can be accommodated. In this embodiment, even in this case, by Fig.25 or Fig.26 The connection configuration shown also realizes the same functions as the case where the number of users is small, such as selecting an arbitrary uplink connection and returning light to an arbitrary subscriber device.

[0121] Fig.25 This is a diagram showing an example of the scalability of the optical SW using a mesh structure. A portion of the ports 11-1 of the optical SW 1010 is connected to the ONU via a transmission path 50-1, and a portion of the ports 11-2 is connected to the uplink transmission path 50-2. Furthermore, a portion of the ports 11-1 of the optical SW 1010 is connected to a portion of the ports 11-2 of another optical SW 1010 via a transmission path 50-3. In this figure, one optical SW 1010 is connected to all other optical SWs 1010.

[0122] The multiple ports 11-1 of the optical SW 1010 are described as ports 11-1-1, 11-1-2, 11-1-3, ..., 11-1-p1, 11-1-p2, 11-1-p3, and the multiple ports 11-2 of the optical SW 1010 are described as ports 11-2-1, 11-2-2, 11-2-3, ..., 11-2-q1, 11-2-q2, 11-2-q3.

[0123] exist Fig.25In the example, ports 11-1-1, 11-1-2, 11-1-3, ... of the optical SW 1010-n (n is an integer greater than 1 and less than N) are connected to ONU #n1, ONU #n2, ONU #n3, ..., and ports 11-2-1, 11-2-2, 11-2-3, ... are connected to the transmission path 50-2 of uplink #n1, uplink #n2, uplink #n3, .... Furthermore, the optical SW 1010-n is connected to ports 11-1 of all other optical SWs 1010-j (j≠n, j is an integer greater than 1 and less than N) through a part of ports 11-2. For example, port 11-2-q1 of optical SW1010-1 is connected to port 11-1-p1 of optical SW1010-2, port 11-2-q2 of optical SW1010-1 is connected to port 11-1-p1 of optical SW1010-3, and port 11-2-q3 of optical SW1010-1 is connected to port 11-1-p1 of optical SW1010-4. In addition, port 11-2-q1 of optical SW1010-2 is connected to port 11-1-p1 of optical SW1010-1, port 11-2-q2 of optical SW1010-2 is connected to port 11-1-p2 of optical SW1010-3, and port 11-2-q3 of optical SW1010-2 is connected to port 11-1-p2 of optical SW1010-4. Furthermore, the optical SW 1010 - n may be connected to the ports 11 - 1 of some optical SW 1010 - j among all other optical SWs 1010 - j (j≠n, j is an integer greater than 1 and less than N) through some ports 11 - 2 .

[0124] For example, ONU #11 sends a wavelength λ to uplink #41. 1 In the case of an uplink optical signal, the optical SW 1010-1 outputs the optical signal input from the port 11-1-1 from the port 11-2-q3. The port 11-1-p1 of the optical SW 1010-4 inputs the wavelength λ output from the port 11-2-q3 of the optical SW 1010-1. 1 The optical signal is output from port 11-2-1.

[0125] ONU#12 sends the wavelength λ to ONU#31. 2 In the case of an uplink optical signal, the optical SW 1010-1 outputs the optical signal input from the port 11-1-2 from the port 11-2-q2. The optical SW 1010-3 inputs the optical signal output from the port 11-2-q2 from the port 11-1-p1. The optical SW 1010-3 receives the wavelength λ input from the port 11-1-p1. 2 The optical signal is Figure 3 The optical SW10b shown in the figure performs similar return communication and is output from the port 11-1-1.

[0126] Furthermore, in Fig.25 In the embodiment, only the uplink optical signal is recorded. In the case of uplink and downlink bidirectional communication, a WDM filter is set in the transmission paths 50-1, 50-2, and 50-3 to separate the uplink optical signal and the downlink optical signal for transmission. Moreover, the downlink optical signal is connected in the opposite direction to the uplink optical signal described above.

[0127] Fig.26 This is a diagram showing another example of the scalability of the optical SW using a cascade structure. Fig.26 The structure shown is Fig.25 The difference of the structure shown is that the optical SW1010-n (n is an integer greater than 1 and less than N) is connected to the port 11-1 of any other optical SW1010-(n+1) through a part of the port 11-2. In addition, it is assumed that the optical SW1010-(N+1) is the optical SW1010-1. Thus, a plurality of optical SW1010 are connected in series.

[0128] exist Fig.26 In the embodiment, ports 11-1-1, 11-1-2, 11-1-3, ... of the optical SW 1010-n (n is an integer greater than 1 and less than N) are connected to ONU #n1, ONU #n2, ONU #n3, ..., and ports 11-2-1, 11-2-2, 11-2-3, ... are connected to the transmission path 50-2 of uplink #n1, uplink #n2, uplink #n3, .... Furthermore, port 11-2-q1 of the optical SW 1010-n is connected to port 11-1-p1 of the optical SW 1010-(n+1), port 11-2-q2 of the optical SW 1010-n is connected to port 11-1-p2 of the optical SW 1010-(n+1), and port 11-2-q3 of the optical SW 1010-n is connected to port 11-1-p3 of the optical SW 1010-(n+1).

[0129] For example, ONU #11 sends a wavelength λ to uplink #41. 1 In the case of an uplink optical signal, the optical SW 1010-1 outputs the optical signal input from the port 11-1-1 from the port 11-2-q1. The optical SW 1010-2 inputs the optical signal output from the port 11-2-q1 from the port 11-1-p1, and transmits the optical signal according to the wavelength λ. 1 The optical signal output from the port 11-2-q1 of the optical SW 1010-2 is input to the port 11-1-p1 of the optical SW 1010-3, and is outputted from the port 11-2-q1 according to the wavelength λ. 1The optical signal output from the port 11-2-q1 of the optical SW 1010-3 is input to the port 11-1-p1 of the optical SW 1010-4, and is outputted from the port 11-2-q1. 1 Output from port 11-2-1.

[0130] ONU#12 sends the wavelength λ to ONU#31. 2 In the case of an uplink optical signal, the optical SW 1010-1 outputs the optical signal input from the port 11-1-2 from the port 11-2-q2. The optical SW 1010-2 inputs the optical signal output from the port 11-2-q2 from the port 11-1-p2. The optical SW 1010-2 outputs the optical signal output from the port 11-2-q2 according to the wavelength λ 2 The optical signal input from the port 11-1-p2 is output from the port 11-2-q2. The optical signal output from the port 11-2-q2 of the optical SW 1010-2 is input to the port 11-1-p2 of the optical SW 1010-3. The optical SW 1010-3 converts the optical signal input from the port 11-1-p2 into a wavelength λ. 2 Conduct with Figure 3 The optical SW10b shown similarly performs return communication and is output from the port 11-1-1.

[0131] Furthermore, in Fig.26 In the embodiment, only the uplink optical signal is recorded. In the case of uplink and downlink bidirectional communication, a WDM filter is set in the transmission paths 50-1, 50-2, and 50-3 to separate the uplink optical signal and the downlink optical signal for transmission. Moreover, the downlink optical signal is connected in the opposite direction to the uplink optical signal described above.

[0132] In each of the embodiments described below, an example of an optical access system using an optical SW having the above-mentioned function will be described.

[0133] (First Embodiment) Fig. 27 1 is a diagram showing a configuration example of an optical access system 100. The optical access system 100 includes an optical gateway (GW) 200 and an operation system (OPS) 300. The subscriber device 40 communicates with the optical access system 100 through the optical access system 100. Figure 1 A higher-level network such as the optical communication network 30 shown is connected so as to be communicable.

[0134] The subscriber device 40 is a device on the optical subscriber side. The subscriber device 40 is connected to the optical GW 200 via a transmission path 501. The transmission path 501 is, for example, an optical fiber. The optical GW 200 is a device located in a communication station. The subscriber device 40 and the optical GW 200 shown by symbol N1 are connected, for example, via a transmission path 501 and a power splitter 502. The structure of the network connected from the subscriber device 40 to the optical GW 200 can also be various network topologies such as PtoP (point to point), PON structure, bus type, etc. For example, it can be configured to have a power splitter 502 in the transmission path 501, and multiple subscriber devices 40 are connected to one transmission path 501. The optical GW 200 is connected to other stations or core networks via transmission paths 511 and 512. The transmission paths 511 and 512 are, for example, optical fibers. The transmission path 511 transmits an uplink signal, and the transmission path 512 transmits a downlink signal. Transmission path 511 and transmission path 512 are examples of multiplexed communication transmission paths for transmitting wavelength-division-multiplexed optical signals. The connection from the optical GW 200 shown by symbol N2 to other local ends or core networks is connected, for example, through the transmission path 511 or the transmission path 512 of the optical fiber, so that the connection between the grounds is connected in a fully meshed manner. In this embodiment, the following case is used as an example for explanation: the optical GW 200 is set at the local end of the ground A, and is connected to the optical communication device set at the local end of the ground B and the optical communication device set at the local end of the ground C via the optical communication network 30, etc. The optical communication devices for the ground B and the ground C connected by the optical GW 200 can also be the optical GW 200.

[0135] The subscriber device 40 is connected to the optical GW 200 via a transmission path 501. The subscriber device 40 has an optical transceiver 41. The optical transceiver 41 is a wavelength-variable optical transceiver. The optical transceiver 41 is, for example, an optical transceiver that converts an optical signal and an electrical signal into each other. The subscriber device 40 can select a unique wavelength according to the transmission and reception destination and set it in the optical transceiver 41. The subscriber device 40 sets the wavelength to be used in the optical transceiver 41 according to the instruction received from the optical GW 200. M (M is an integer greater than 1) subscriber devices 40 connected to the optical GW 200 are recorded as subscriber devices 40-1 to 40-M.

[0136] The optical GW 200 includes an optical SW 210, a wavelength multiplexer / demultiplexer 220, a control device 230, a multiplexer 241, a demultiplexer 242, a branching unit 250, and a monitoring device 260. The branching unit 250 and the monitoring device 260 are examples of a monitoring unit.

[0137] The optical SW 210 has a plurality of input and output ports (hereinafter referred to as "ports"), and connects two or more ports. The optical SW 210 can freely switch the optical path between the ports. The port for inputting and outputting an upstream signal is recorded as an upstream port, and the port for inputting and outputting a downstream signal is recorded as a downstream port. Each port of the optical SW 210 is connected to a transmission path.

[0138] The wavelength multiplexer / demultiplexer 220 performs uplink / downlink multiplexing and separation according to wavelength separation of the uplink signal and the downlink signal. The wavelength multiplexer / demultiplexer 220 inputs the uplink optical signal sent by the subscriber device 40 from the transmission path 501, and outputs it to the optical SW 210 via the transmission path 521. In addition, the wavelength multiplexer / demultiplexer 220 inputs the downlink optical signal output by the optical SW 210 from the transmission path 522, and outputs it to the subscriber device 40 via the transmission path 501.

[0139] The control device 230 is connected to the upstream port and the downstream port of the optical SW 210 to which the subscriber device 40 is not connected. The upstream port of the optical SW 210 is connected to the port on the transmission side of the control device 230 through the transmission path 531. The downstream port of the optical SW 210 is connected to the port on the transmission side of the control device 230 through the transmission path 533. The control device 230 has a wavelength splitter 231, an optical receiver (Rx) 232 for each wavelength channel, and a wavelength variable transmitter 233. The wavelength splitter 231 is, for example, AWG (arrayed waveguide gratings). The wavelength splitter 231 splits the light input to the port on the receiving side via the transmission path 540 according to the wavelength. The wavelength splitter 231 outputs the split light to the optical receiver 232 that receives the optical signal of the wavelength of the light. The wavelength variable transmitter 233 has a wavelength variable laser diode (LD) that generates light of variable wavelength. The variable wavelength transmitter 233 transmits an optical signal with a variable wavelength using light generated by a variable wavelength laser diode. The variable wavelength transmitter 233 outputs an optical signal using the generated light from a transmission-side port to the transmission path 533 .

[0140] The combiner 241 combines the upstream optical signals of different wavelengths outputted from each of the plurality of transmission paths 541 by the optical SW 210, and outputs the signals to the transmission path 511 connected to the other ground. The demultiplexer 242 inputs the optical signal transmitted from any other ground from the transmission path 512, and demultiplexes the input downstream optical signal according to the wavelength. The demultiplexer 242 inputs the demultiplexed downstream optical signal to the optical SW 210 via the plurality of transmission paths 542, respectively, and the plurality of transmission paths 542 are connected to the upstream ports corresponding to the wavelengths of the optical signals.

[0141] The transmission path 511 and the transmission path 512 are provided with a branching unit 250. The branching unit 250 has power dividers 251 and 252. The power divider 251 divides the uplink optical signal transmitted in the transmission path 511, and inputs it to the optical SW 210 via the transmission path 551. The power divider 252 divides the downlink optical signal transmitted in the transmission path 512, and inputs it to the optical SW 210 via the transmission path 552.

[0142] The monitoring device 260 has a wavelength demultiplexer 261 and an optical receiver (Rx) 262 for each wavelength. The wavelength demultiplexer 261 is connected to the optical SW 210 via the transmission path 560. The optical SW 210 outputs the optical signal input from the port connected to the transmission path 541 or the transmission path 542 to the port connected to the transmission path 560. Thus, the wavelength demultiplexer 261 receives the optical signal branched from the branching section 250. The wavelength demultiplexer 261 demultiplexes the input optical signal for each wavelength. The wavelength demultiplexer 261 outputs the demultiplexed light to the optical receiver 262 that receives the optical signal of the wavelength of the light. The monitoring device 260 monitors the state of the communication sent and received by the subscriber device 40 through the optical signal received by the optical receiver 262.

[0143] OPS300 includes an optical GW control unit 301 and a management DB 350. The optical GW control unit 301 is connected to the optical GW 200. The optical GW control unit 301 includes a wavelength control unit 310 and an optical SW control unit 320. The wavelength control unit 310 stores information indicating the wavelength of light used by each user (or each service). The wavelength control unit 310 refers to the information and dynamically allocates the wavelength used by each user. The wavelength control unit 310 may also be set in a building different from the optical GW 200 and connected to the optical SW 210 and the optical SW control unit 320 via a network. The wavelength control unit 310 manages and controls information on which user is connected to which port of the optical SW 210 and which wavelength is used in real time by sharing each connection information.

[0144] In addition, the optical GW control unit 301 is connected to a management database (DB) 350. The optical GW control unit 301 and the management DB 350 exchange information related to users and used wavelengths. The management DB 350 stores the used wavelength and destination information of each user. The destination is represented by, for example, ground A, ground B, etc. The management DB 350 manages information of all users connected to the optical access system 100.

[0145] Fig.282 is a diagram showing an example of a SW connection table. The SW connection table shows the connection destination of each port of the optical SW 210. That is, the port for inputting and outputting an optical signal can be used as information for identifying the subscriber device 40, the control device 230, the branch unit 250, the monitoring device 260, the ground, etc., which are the transmission source or the transmission destination of the optical signal.

[0146] The wavelength table includes a user wavelength table and an inter-office wavelength table.

[0147] Fig.29 2 is a diagram showing an example of a user wavelength table. The user wavelength table shows wavelengths used by each user for transmission, wavelengths used for reception, idle wavelengths not used for transmission and reception, and wavelengths that cannot be used due to failure. In addition, the management DB 350 may manage the wavelength table for each transmission path connected to the optical SW 210.

[0148] Fig.30 The diagram shows an example of an inter-office wavelength table. The inter-office wavelength table shows wavelengths used by a certain location in communication with other locations, idle wavelengths not used in communication with other locations, and wavelengths that cannot be used in communication with other locations due to failure.

[0149] Next, use Fig.31 and Fig.32 A configuration example of the subscriber device 40 will be described. Fig.31 4 is a structural diagram of a two-core subscriber device 401. The subscriber device 401 has an optical transceiver 411. The optical transceiver 411 has a wavelength-variable light source 451, a wavelength-variable filter 452, and a receiver 453. The wavelength-variable light source 451 is an example of an optical transmitter, and the wavelength-variable filter 452 and the receiver 453 are examples of an optical receiver. The wavelength-variable light source 451 outputs light of a set wavelength. The wavelength set in the wavelength-variable light source 451 is variable. The wavelength-variable filter 452 receives an optical signal from the transmission path 501 and allows the light of the set wavelength to pass through the receiver 453. The wavelength set in the wavelength-variable filter 452 is variable. The receiver 453 receives the optical signal passed by the wavelength-variable filter 452. The wavelength-variable light source 451 can output a main signal (or a signal in which a control signal is superimposed on the main signal) by direct modulation, for example. Alternatively, the wavelength-variable light source 451 also has an external modulator, and can use the external modulator to output the main signal (or a signal in which a control signal is superimposed on the main signal). Depending on the configuration of the optical GW, the multiplexing method, etc., the subscriber device 401 on the receiving side may also adopt a configuration that does not use the wavelength variable filter 452 .

[0150] Fig.32 4 is a block diagram of a heart-shaped subscriber device 402. The subscriber device 402 includes an optical transceiver 412. Fig.32 The optical transceiver 412 is shown with Fig.31 The optical transceiver 411 shown is different in that it also includes a WDM filter 454. The WDM filter 454 separates the uplink signal and the downlink signal according to the wavelength. The WDM filter 454 outputs the light generated by the wavelength-variable light source 451 to the transmission path 501, and outputs the optical signal input from the transmission path 501 to the wavelength-variable filter 452. The wavelength-variable light source 451 can output the main signal (or a signal with a control signal superimposed on the main signal) by direct modulation, for example. Alternatively, the subscriber device 402, like the subscriber device 401, also has an external modulator, and can use the external modulator to output the main signal (or a signal with a control signal superimposed on the main signal). Depending on the structure of the optical GW, the multiplexing method, etc., the subscriber device 402 on the receiving side can also adopt a structure that does not use the wavelength-variable filter 452.

[0151] Here, the operation when a subscriber device 40 is newly connected will be described. Fig.33 1 is a flowchart showing the initial setting process of the optical access system 100 when a new subscriber device is connected. Fig. 27 and Fig.33 The operation of the optical access system 100 when the subscriber device 40-1 is newly connected to the optical GW 200 is described. It is assumed that the control device 230 has confirmed in advance which port of the optical SW 210 each port of the wavelength demultiplexer 261 (AWG) is connected to.

[0152] First, before connecting a new subscriber device 40-1, a user application is performed. For example, through the user application, communication between ground A and ground B can be performed. Based on the user application, the operator registers the user information, the initial destination information, etc. in the management DB350 of OPS300 (step S1). The user information is, for example, information that can obtain the wavelength that can be used by the optical transceiver 41. OPS300 refers to the SW connection table and allocates the port of the optical SW210 connected to the subscriber device 40-1 from the idle ports of the optical SW210. Here, an uplink port and a downlink port are allocated. OPS300 registers information showing that the allocated port is connected to the subscriber device 40-1 in the SW connection table (step S2). The optical SW control unit 320 of OPS300 controls the optical SW210 so that optical signals are transmitted and received between the port allocated to the subscriber device 40-1 and the port connected to the control device 230.

[0153] When a new subscriber device 40-1 is connected, the subscriber device 40-1 performs initialization processing and sends a connection request (registration request) through an optical signal (step S3). The subscriber device 40-1 automatically performs initialization processing before or after the connection. The wavelength multiplexer / demultiplexer 220 inputs the connection request from the transmission path 501 and outputs it to the optical SW 210 via the transmission path 521. The optical SW 210 sends the connection request input from the port connected to the subscriber device 40-1 to the output port connected to the control device 230. The control device 230 inputs the connection request from the receiving port via the transmission path 531. The control device 230 analyzes the input optical signal and confirms whether there is no problem in the initial setting wavelength and optical power (step S4).

[0154] If there is a problem with the wavelength or optical power, the control device 230 sends a restart or initialization instruction to the subscriber device 40-1. After the restart or initialization, the process returns to step S3, and the subscriber device 40-1 sends a connection request again.

[0155] The control device 230 analyzes the optical signal received from the subscriber device 40-1, and outputs a connection request to the optical GW control unit 301 when confirming that there is no problem. The optical GW control unit 301 registers the information of the subscriber device 40-1 in the management DB 350. The connection request includes information of the connection source, information of the connection destination, the type of signal to be transmitted, etc. The information of the connection source uses address information such as a MAC (Medium Access Control) address, etc. The information of the connection destination uses, for example, address information of the destination, etc. The type of signal to be transmitted, for example, the service used, the modulation method, etc. Based on this information, the wavelength control unit 310 registers the information of the connection source in the management DB 350. As a result, the identification of the user using the subscriber device 40-1 and the meaning that the wavelength available to the subscriber device 40-1 is idle are set in the user wavelength table. Furthermore, the wavelength control unit 310 compares the connection information stored in the management DB 350 to calculate the best path between the subscriber device 40-1 and the communication destination, such as between the ground A and the ground B. The wavelength control unit 310 searches for available wavelengths shown in the inter-central office wavelength table based on the calculated path. The wavelength control unit 310 selects a wavelength to be used by the subscriber device 40-1 from the available wavelengths, and transmits information on the selected wavelength to the control device 230 (step S5).

[0156] The other subscriber device 40 that is the communication destination of the subscriber device 40-1 is described as the communication destination subscriber device 40. In this case, the wavelength control unit 310 selects a transmission wavelength and a reception wavelength, wherein the transmission wavelength is a wavelength used by the subscriber device 40-1 to transmit an optical signal to the communication destination subscriber device 40, and the reception wavelength is a wavelength used by the subscriber device 40-1 to receive an optical signal from the communication destination subscriber device 40. The wavelength control unit 310 transmits the selected transmission wavelength and reception wavelength to the control device 230 as wavelengths used by the subscriber device 40-1. In addition, when the subscriber device 40-1 only transmits to the communication destination subscriber device 40, the wavelength control unit 310 may not select the reception wavelength. In addition, when the subscriber device 40-1 only receives from the communication destination subscriber device 40, the wavelength control unit 310 may not select the transmission wavelength.

[0157] The control device 230 transmits the wavelength information as follows. The variable wavelength transmitter 233 of the control device 230 transmits a wavelength instruction for setting the wavelength information selected by the wavelength control unit 310 through an optical signal indicating the wavelength to be transmitted to the subscriber device 40-1. The optical SW 210 outputs the optical signal input from the port connected to the variable wavelength transmitter 233 to the transmission path 522 connected to the subscriber device 40-1. The wavelength multiplexer / demultiplexer 220 inputs the optical signal input from the optical SW 210 via the transmission path 522 to the transmission path 501. The subscriber device 40-1 receives the optical signal transmitted in the transmission path 501. The subscriber device 40-1 sets the oscillation wavelength of the optical transceiver 41 according to the wavelength instruction indicated by the received optical signal (step S6). That is, the subscriber device 40-1 sets the oscillation wavelength of the optical transceiver 41 (variable wavelength light source 451) so that the optical signal is transmitted at the transmission wavelength set in the wavelength instruction. When the wavelength for reception is set in the wavelength instruction, the subscriber device 40 - 1 sets the optical transceiver 41 (variable wavelength filter 452 ) so as to receive a wavelength signal of the wavelength for reception.

[0158] The optical transceiver 41 of the subscriber device 40-1 transmits a notification signal through an optical signal of the indicated wavelength, and the notification signal notifies that the wavelength has been set. The notification signal is sent to the control device 230 in the same manner as the request signal. Based on the received notification signal, the control device 230 confirms whether the designated wavelength is correctly set, whether the output power is sufficient, etc. (step S7). If the result of the confirmation is that there is no problem, the control device 230 sends a permission notification to the subscriber device 40-1 through an optical signal, and the permission notification indicates permission to start communication. The permission notification is sent to the subscriber device 40-1 in the same manner as the wavelength indication.

[0159] Furthermore, the optical SW control unit 320 transmits connection information of the best port in the optical SW 210 to the optical SW 210 in accordance with the transmission destination of the subscriber device 40-1. Based on the connection information, the optical SW 210 sets the uplink port and the downlink port of the subscriber device 40-1 according to the instruction from the optical SW control unit 320 (step S8).

[0160] In addition, the optical access system 100 controls the timing so that the path switching within the optical SW 210 is performed after the permission to start communication is sent from the control device 230 to the subscriber device 40-1. For example, it is assumed that the time required for the path switching of the optical SW 210 is known in advance. In this case, after the subscriber device 40-1 receives the permission to start communication, the control device 230 waits for the time required from the receipt of the instruction to switch the path from the optical SW 210 to the actual switching of the path before actually starting the communication. After the communication starts, the monitoring device 260 of the optical GW 200 confirms the communication status between the relative subscriber devices (step S9). The monitoring device 260 notifies the OPS 300 of the confirmation result. In the case of confirmation as NG, the OPS 300 performs a cause analysis operation sequence.

[0161] The connection request sent by the subscriber device 40-1 and the control signal sent by the control device 230 to the subscriber device 40-1 are optical signals with a lower speed than the main signal. For example, a control signal (control method) without a protocol such as AMCC can be used as the control signal.

[0162] In addition, the OPS 300 instructs the communication destination subscriber device 40 to use the transmission wavelength of the subscriber device 40-1 as the reception wavelength of the communication destination subscriber device 40, and further, to use the reception wavelength of the subscriber device 40-1 as the transmission wavelength of the communication destination subscriber device 40. For example, in the optical GW control unit 301 that controls the optical GW 200 that accommodates the communication destination subscriber device 40, the wavelength control unit 310 instructs the control device 230 to transmit a wavelength instruction that sets the reception wavelength and the transmission wavelength of the communication destination subscriber device 40. The communication destination subscriber device 40 receives the wavelength instruction from the control device 230 through a control signal, and sets the reception wavelength and the transmission wavelength in the optical transceiver 41 according to the received wavelength instruction. That is, when the transmission wavelength is set in the wavelength instruction, the communication destination subscriber device 40 sets the oscillation wavelength of the optical transceiver 41 (variable wavelength light source 451) so that the optical signal is transmitted using the transmission wavelength. When the wavelength for reception is set in the wavelength instruction, the communication destination subscriber device 40 sets the optical transceiver 41 (variable wavelength filter 452) so as to receive a wavelength signal of the wavelength for reception.

[0163] Furthermore, the optical access system 100 can transmit and receive information registered by the user in the management DB 350 between the new subscriber device 40-1 and the optical GW control unit 301 without performing the user application in step S1. Thus, the subscriber device 40-1 can communicate with other subscriber devices 40 without performing the user application. The transmission and reception of information between the subscriber device 40-1 and the optical GW control unit 301 is performed via the control device 230 using, for example, AMCC.

[0164] In the above, the operation when a new subscriber device is connected is described. Fig. 27 The normal communication operation after a new subscriber device is connected will be described by taking the case where the new subscriber device 40-2 communicates with the new subscriber device 40-2 as an example.

[0165] First, the uplink optical signal outputted by the subscriber device 40-2, which will be described for the uplink communication, is sent to the optical GW 200 via the transmission path 501. The wavelength multiplexer / demultiplexer 220 of the optical GW 200 separates the input optical signal into an uplink optical signal and a downlink optical signal according to the wavelength. The uplink optical signal demultiplexed by the wavelength multiplexer / demultiplexer 220 is inputted to the optical SW 210 via the transmission path 521. The optical SW 210 connects the port to which the uplink optical signal is inputted from the wavelength multiplexer / demultiplexer 220 to the other port corresponding to the path to the destination of the subscriber device 40-2, and outputs the optical signal. In the case where the wavelength is used as the destination information, the optical SW 210 connects to the other port corresponding to the destination specifically designated according to the wavelength assigned to the subscriber device 40-2, and outputs the optical signal. The uplink signal outputted from the optical SW 210 is multiplexed in the multiplexer 241 with the optical signals of different wavelengths transmitted by other subscriber devices 40, and is transmitted to other central offices (for example, to ground B) via a transmission path 511. The combiner 241 combines wavelength channels for each local end such as ground B and ground C. Furthermore, by separating the transmission path 511 with ground B and the transmission path 511 with ground C, the same wavelength can be used for ground B and ground C.

[0166] Next, the communication in the downstream direction is described. Downstream is the communication in the direction from the ground B, C to the subscriber device 40. The downstream optical signal is sent to the optical GW 200 via a transmission path 512. The demultiplexer 242 of the optical GW 200 demultiplexes the downstream optical signal transmitted in the transmission path 512 according to the wavelength. The demultiplexer 242 inputs the demultiplexed light to the downstream port corresponding to the wavelength of the demultiplexed light via the transmission path 542. The optical SW 210 connects the port to which the downstream optical signal is input from the demultiplexer 242 to other ports corresponding to the wavelength to output the optical signal. The wavelength multiplexer / demultiplexer 220 separates the optical signal input from the optical SW 210 via the transmission path 522 into an upstream optical signal and a downstream optical signal according to the wavelength. The downstream optical signal demultiplexed by the wavelength multiplexer / demultiplexer 220 is input to the subscriber device 40-2 via the transmission path 501. It is assumed that the wavelength channels transmitted from the optical GW 200 to the respective central offices (such as the terminals B and C) are of the same wavelength band, but different wavelength bands may be used for each central office.

[0167] The monitoring device 260 of the optical GW 200 receives the light branched from the branching unit 250. The light branched from the branching unit 250 is an optical signal transmitted and received by each subscriber device 40. The monitoring device 260 monitors the signals transmitted and received by each subscriber device 40 by monitoring the received optical signal. When an abnormality such as wavelength deviation, output reduction, or communication abnormality is detected through monitoring, the monitoring device 260 sends a signal of abnormality detection to the optical GW control unit 301. The optical SW control unit 320 of the optical GW control unit 301 controls the optical SW 210 so that the target subscriber device 40 is connected to the control device 230 again. Then, similar to the case of newly connecting a subscriber device 40, the optical GW control unit 301 performs a process of allocating a new wavelength different from the wavelength used when the abnormality was detected. Thus, when an optical signal of a wavelength after the change is input from the subscriber device 40, the optical SW 210 connects the input optical signal to the port of the subscriber device 40 specified by the wavelength before the change.

[0168] Although Fig. 27 The optical GW200 shown performs wavelength division multiplexing, but as Fig.34 and Fig.35 As shown, wavelength division multiplexing may not be performed. Fig.34 It is a diagram showing a configuration example of the optical access system 101 . Fig.34 The optical access system 101 shown is Fig. 27The optical access system 100 shown is different in that it is provided with an optical GW 201 instead of the optical GW 200. The optical GW 201 is different from the optical GW 200 in that it is provided with a wavelength combiner / demultiplexer 243 and a branching unit 250a instead of the combiner 241, the demultiplexer 242 and the branching unit 250. The optical GW 201 is connected to the communication device of the local end of other ground through the transmission path 503. One transmission path 503 transmits uplink signals and downlink signals between any ground.

[0169] The wavelength multiplexer / demultiplexer 243 separates the input optical signal into an uplink optical signal and a downlink optical signal according to the wavelength. The wavelength multiplexer / demultiplexer 243 separates the uplink optical signal input from the optical SW 210 via the transmission path 543-1, and sends it to other ground or upper network via the transmission path 503. In addition, the wavelength multiplexer / demultiplexer 243 separates the downlink optical signal input from other ground via the transmission path 503, and outputs it to the optical SW 210 via the transmission path 543-2.

[0170] The transmission path 503 is provided with a branching portion 250a. The branching portion 250a has a power splitter 251a. The power splitter 251a branches the uplink and downlink optical signals transmitted in the transmission path 503. The power splitter 251a inputs the branched uplink optical signal to the port of the optical SW 210 via the transmission path 551a, and inputs the branched downlink optical signal to the port of the optical SW 210 via the transmission path 551b. The optical SW 210 outputs the optical signal input from the port connected to the transmission path 551a and the optical signal input from the port connected to the transmission path 551b from the port connected to the transmission path 560. Thus, the wavelength demultiplexer 261 of the monitoring device 260 receives the optical signal branched from the branching portion 250a.

[0171] Fig.35 It is a diagram showing a configuration example of the optical access system 102 . Fig.35 The optical access system 102 shown is Fig.34 The optical access system 101 shown is different in that an optical GW 202 is provided instead of the optical GW 201. The optical GW 202 is different from the optical GW 201 in that a wavelength multiplexer 244, a wavelength multiplexer 245 and a branching unit 250b are provided instead of the wavelength multiplexer 243 and the branching unit 250a.

[0172] The wavelength multiplexer / demultiplexer 244 separates the uplink optical signal and the downlink optical signal according to the wavelength. The wavelength multiplexer / demultiplexer 244 inputs the uplink optical signal input from the optical SW 210 via the transmission path 544 to the wavelength multiplexer / demultiplexer 245 via the transmission path 545. The wavelength multiplexer / demultiplexer 244 inputs the downlink optical signal input from the wavelength multiplexer / demultiplexer 245 via the transmission path 546 to the optical SW 210 via the transmission path 544.

[0173] The wavelength multiplexer / demultiplexer 245 separates the uplink optical signal and the downlink optical signal according to the wavelength. The wavelength multiplexer / demultiplexer 245 sends the uplink optical signal input from the wavelength multiplexer / demultiplexer 245 via the transmission path 545 to other ground or upper network via the transmission path 503. In addition, the wavelength multiplexer / demultiplexer 245 inputs the downlink optical signal received via the transmission path 503 to the wavelength multiplexer / demultiplexer 244 via the transmission path 546.

[0174] The branching section 250b includes a power splitter 251b and a power splitter 252b. The power splitter 251b branches the uplink optical signal transmitted in the transmission path 545. The power splitter 251b inputs the branched uplink optical signal to the port of the optical SW 210 via the transmission path 551b. The power splitter 252b branches the downlink optical signal transmitted in the transmission path 546. The power splitter 252b inputs the branched downlink optical signal to the port of the optical SW 210 via the transmission path 552b. The optical SW 210 outputs the optical signal input from the port connected to the transmission path 551b and the optical signal input from the port connected to the transmission path 552b from the port connected to the transmission path 560. Thus, the wavelength demultiplexer 261 of the monitoring device 260 receives the optical signal branched from the branching section 250b.

[0175] The monitoring device 260 described above has a receiver structure having a wavelength splitter 261 and an optical receiver 262 for each wavelength. The monitoring device may also have a wavelength-variable optical receiver instead of the receiver structure. In addition, the transceiver of the control device may also be a receiver structure that may have a transmitter with a fixed wavelength but not a wavelength splitter. Fig.36 An example of this structure is shown below.

[0176] Fig.36 It is a diagram showing a configuration example of the optical access system 103 . Fig.36 The optical access system 103 shown is Fig. 27 The optical access system 100 shown is different in that it is provided with an optical GW 203 instead of the optical GW 200. The optical GW 203 is different from the optical GW 200 in that it is provided with a control device 235 and a monitoring device 265 instead of the control device 230 and the monitoring device 260. The control device 235 has an optical receiver 236 and an optical transmitter 237 that is not wavelength-variable. The monitoring device 265 has a wavelength-variable optical receiver 266.

[0177] In addition, the monitoring device may be connected via a light SW different from the above-mentioned light SW. Fig.37 An example of this structure is shown below. Fig.37 It is a diagram showing a configuration example of the optical access system 104 . Fig.37 The optical access system 104 shown is Fig.36 The optical access system 103 shown is different in that an optical GW 204 is provided instead of the optical GW 203. The optical GW 204 is different from the optical GW 203 in that an optical SW 211 is further provided, and a monitoring device 265 is connected to the optical SW 211.

[0178] The uplink optical signal separated from the transmission path 511 by the power splitter 251 of the branching unit 250 is input to the optical SW 211 via the transmission path 555, and the downlink optical signal separated from the transmission path 512 by the power splitter 252 is input to the optical SW 211 via the transmission path 555. The optical SW 211 is, for example, a small optical SW. The number of ports of the optical SW 211 is 1 port on the monitoring device 260 side, and 2M ports on the side where the monitored optical signal is input. 2M is twice the number M of the subscriber devices 40 connected to the optical GW 204. In addition, instead of using a small optical SW, a monitoring device corresponding to the number of connected grounds may be prepared to monitor the signals transmitted and received with all the grounds for each ground.

[0179] (Second Embodiment) This embodiment uses a return transmission path to communicate between a plurality of subscriber devices connected to the same optical GW. The following description will focus on the differences from the first embodiment.

[0180] Fig.38 It is a diagram showing a configuration example of the optical access system 105 . Fig.38 The optical access system 105 shown is Fig.36 The optical access system 103 shown is different in that it is provided with an optical GW 205 instead of the optical GW 203. The optical GW 205 is different from the optical GW 203 in that it is further provided with a combiner 247 and a demultiplexer 248 corresponding to the ground A where the optical GW 205 is provided. The combiner 247 and the demultiplexer 248 are connected via a transmission path 547. The transmission path 547 is a return transmission path.

[0181] Similar to the combiner 241, the combiner 247 combines the uplink optical signals of different wavelengths outputted from each of the plurality of transmission paths 541 by the optical SW 210, and outputs them to the transmission path 547. Similar to the demultiplexer 242, the demultiplexer 248 demultiplexes the downlink optical signals inputted from the transmission path 547 according to the wavelength. The demultiplexer 248 inputs the demultiplexed downlink optical signals to the optical SW 210 via the plurality of transmission paths 542, respectively, and the plurality of transmission paths 542 are connected to the downlink ports corresponding to the wavelengths of the optical signals. In addition, the transmission path 547 is provided with a branching unit 250.

[0182] In the first embodiment, the subscriber device connected to the ground A is connected to the port for connecting to the ground B and the ground C via the optical SW. In the present embodiment, a combination of the combiner 241 and the splitter 242 connected to the ground B or the ground C is added. The added combination is a combiner 247 and a splitter 248. Then, the output port of the added combiner 247 and the input port of the added splitter 248 are connected through the transmission path 547. With this structure, the signal output by the subscriber device 40 can be input to the optical SW 210 again. Thus, the optical GW 205 returns the optical signal output by a certain subscriber device 40 and again inputs the optical SW 210 as a downlink signal. By connecting the returned signal to other subscriber devices 40 in the optical SW 210, return communication, that is, communication between subscriber devices 40 connected to the same optical GW 205 can be realized.

[0183] For example, the state in which the subscriber device 40-2 and the subscriber device 40-M communicate is described. It is assumed that the K (K is an integer greater than or equal to 2) uplink ports of the optical SW 210 corresponding to the ground A are connected to the combiner 247 via the transmission path 541, and the K downlink ports of the optical SW 210 corresponding to the ground A are connected to the demultiplexer 248 via the transmission path 542. Then, it is assumed that the k-th (k is an integer greater than or equal to 1 and less than or equal to K) uplink port and downlink port of the K downlink ports and uplink ports corresponding to the ground A correspond to the wavelength λ. k The wavelength λ output from the subscriber device 40-2 1 The uplink optical signal is connected to the first uplink port corresponding to the ground A. The input optical signal is returned through the transmission path 547 and input again to the optical SW 210 as a downlink optical signal from the first downlink port corresponding to the ground A. The optical SW control unit 320 sets the path in the optical SW 210 so that the optical signal is sent to the subscriber device 40-M according to the wavelength. Similarly, the wavelength λ output from the subscriber device 40-M k The uplink optical signal is connected to the k-th uplink port corresponding to the ground A. The input optical signal is returned through the transmission path 547 and input again to the optical SW 210 from the k-th downlink port corresponding to the ground A as a downlink optical signal. The optical SW control unit 320 sets the path in the optical SW 210 so that the optical signal is transmitted to the subscriber device 40-2 according to the wavelength. Thus, communication is performed between the subscriber device 40-2 and the subscriber device 40-M.

[0184] use Fig.39 and Fig.40 Another structure of this embodiment will be described. Fig.39 It is a diagram showing a configuration example of the optical access system 106 . Fig.39 The optical access system 106 shown is Fig.38The optical access system 105 shown is different in that it has an optical GW 206 instead of the optical GW 205. The optical GW 206 is different from the optical GW 205 in that it is configured without a combiner 247 and a demultiplexer 248, does not perform wavelength division multiplexing, and directly connects the uplink port and the downlink port for ground A of the optical SW 210 through a transmission path 548, thereby returning the signal.

[0185] Fig.40 It is a diagram showing a configuration example of the optical access system 107 . Fig.40 The optical access system 107 shown is Fig.38 The optical access system 105 shown is different in that it is provided with an optical GW 207 instead of the optical GW 205. The optical GW 207 is different from the optical GW 205 in that it is provided with a power splitter 270 instead of the splitter 248. The power splitter 270 branches the downstream optical signal input from the combiner 247 via the transmission path 547 into a plurality of branches, and inputs the branches to the optical SW 210 via the plurality of transmission paths 542.

[0186] Furthermore, you can also Fig.38 A power splitter is provided at the subsequent stage of the splitter 248 of the optical GW 205. The power splitter branches the optical signal split by the splitter 248 into a plurality of optical signals and inputs the optical signals to different ports of the optical SW 210. In this way, multicast communication of the return communication can be realized.

[0187] The differences from the optical access system 103 are described above; however, the differences can also be applied to the optical access systems 100 , 101 , and 102 .

[0188] (Third Embodiment) The optical access system of this embodiment performs multicast communication. In this embodiment, the difference from the first and second embodiments will be mainly described.

[0189] First, use Fig.41 Multicast in downlink communication will be described. Fig.41 It is a diagram showing a configuration example of the optical access system 108 . Fig.41 The optical access system 108 shown is Fig.40 The optical access system 107 shown is different in that an optical GW 208 is provided instead of the optical GW 207. The optical GW 208 is different from the optical GW 207 in that a transmission path 549 connected to the return port of the optical SW 210 is further provided.

[0190] The case of multicasting the downstream optical signal transmitted from the ground C is described. The optical SW control unit 320 controls so that the port to which the downstream optical signal from the ground C is input is connected to the port for return connected to the transmission path 549 according to the wavelength. As a result, the downstream optical signal from the ground C is transmitted in the transmission path 549 and input to the optical SW 210 again as an upstream signal to the ground A. In addition, the optical SW control unit 320 controls so that the downstream optical signal input from the return port is connected to the port for the upstream signal to the ground A in the same manner as in the second embodiment. As a result, the optical signal returned in the transmission path 549 and input to the optical SW 210 is output to the port connected to the combiner 247. The combiner 247 combines the optical signals output from the optical SW 210 through each of the plurality of transmission paths 541 and outputs them to the transmission path 547. The optical signal output to the transmission path 547 is branched into a plurality of optical signals in the power divider 270. The power splitter 270 inputs the branched optical signals as downlink signals to the ground A to the optical SW 210 via the multiple transmission paths 542. The optical SW 210 outputs the optical signals input from the transmission paths 542 to the port connected to the subscriber device 40 according to the wavelength. This enables multicasting of downlink signals.

[0191] Next, use Fig.42 To illustrate multicast for upstream communication. Fig.42 This is a diagram showing a configuration example of the optical access system 109 . Fig.42 The optical access system 109 shown is Fig.36 The optical access system 103 shown is different in that it is provided with an optical GW 209 instead of the optical GW 203. The optical GW 209 is different from the optical GW 203 in that it is further provided with a transmission path 570 for connecting the return port to the optical SW 210, and a power splitter 271 for multicast. The power splitter 271 is connected to the optical SW 210 via a transmission path 572 and a plurality of transmission paths 573.

[0192] The case of multicasting the uplink optical signal sent from the ground A is described. The optical SW control unit 320 controls so that the port to which the uplink optical signal from the ground A is input is connected to the port for return connected to the transmission path 570 according to the wavelength. As a result, the uplink optical signal from the ground A is transmitted in the transmission path 570 and input to the optical SW 210 again. In addition, the optical SW control unit 320 controls so that the optical signal input from the return port is output to the port connected to the power divider 271. As a result, the optical signal returned in the transmission path 570 and input to the optical SW 210 is output to the transmission path 572. The optical signal output to the transmission path 572 is branched into a plurality of optical signals in the power divider 271. The power divider 271 inputs the branched plurality of optical signals as uplink signals to the optical SW 210 via a plurality of transmission paths 573. The optical SW 210 outputs the optical signal input from each transmission path 573 to the port connected to the ground B or the ground C according to the wavelength. In this way, multicast of uplink signals can be achieved.

[0193] Next, use Fig.43 The following describes a structure in which point-to-multipoint communication (including uplink communication) is performed while multicasting is performed for downlink communication. Fig.43 It is a diagram showing a configuration example of the optical access system 110 . Fig.43 The optical access system 110 shown is Fig.36 The optical access system 103 shown is different in that it is provided with an optical GW 2010 instead of the optical GW 203. The optical GW 2010 is different from the optical GW 203 in that it is further provided with transmission paths 574, 575 and power splitters 272, 273 for connecting the return port to the optical SW 210. The power splitter 272 is connected to the optical SW 210 via a transmission path 581 and a plurality of transmission paths 582. The power splitter 273 is connected to the optical SW 210 via a plurality of transmission paths 583 and a transmission path 584.

[0194] The case of multicasting the downstream optical signal transmitted from the ground C is described. The optical SW control unit 320 controls so that the port to which the downstream optical signal from the ground C is input is connected to the port for return connected to the transmission path 574 according to the wavelength. As a result, the downstream optical signal from the ground C is transmitted in the transmission path 574, and is input to the optical SW 210 again as an upstream signal to the ground A. In addition, the optical SW control unit 320 controls so that the downstream optical signal input from the return port is output to the port connected to the power splitter 272. As a result, the optical signal that is returned in the transmission path 574 and input to the optical SW 210 is output to the transmission path 581. The optical signal output to the transmission path 581 is branched into a plurality of optical signals in the power splitter 272. The power splitter 272 inputs the branched plurality of optical signals as downstream signals to the optical SW 210 via the plurality of transmission paths 582. The optical SW 210 outputs the optical signal input from each transmission path 582 to the port connected to the subscriber device 40 according to the wavelength. This enables multicasting of the downstream signal.

[0195] The case where an uplink optical signal transmitted from ground A is transmitted to ground C is described. The optical SW control unit 320 controls so that the port to which the uplink optical signal from ground A is input is connected to the port connected to the power divider 273 according to the wavelength. As a result, the uplink optical signal from ground A is output to the transmission path 583. The optical signal output to each of the plurality of transmission paths 583 is multiplexed in the power divider 273. The power divider 273 inputs the multiplexed optical signal to the optical SW 210 via the transmission path 584. The optical SW 210 controls so that the optical signal input from the transmission path 584 is connected to the return port connected to the transmission path 575. As a result, the optical signal is transmitted in the transmission path 575 and is input again to the optical SW 210. The optical SW 210 outputs the optical signal input from the transmission path 575 to the multiplexer 241 connected to ground C according to the wavelength.

[0196] As described above, by providing a configuration using two sets of power splitters for multicast, not only downlink multicast communication but also point-to-multipoint communication including uplink communication can be realized.

[0197] (Fourth Embodiment) In this embodiment, communication is performed without separating the uplink signal and the downlink signal. The following description will focus on the differences from the above-mentioned embodiment.

[0198] Fig.44 This is a diagram showing a configuration example of the optical access system 111 . Fig.44 The optical access system 111 shown is Fig.38The optical access system 105 shown is different in that it has an optical GW 2011 instead of the optical GW 205. The optical GW 2011 is different from the optical GW 205 in that it does not have the wavelength multiplexer / demultiplexer 220; it has a wavelength multiplexer / demultiplexer 249 and a branching unit 253 instead of the multiplexer 241, the demultiplexer 242 and the branching unit 250; and it also has a wavelength multiplexer / demultiplexer 238.

[0199] The wavelength multiplexer / demultiplexer 249 is connected to the optical SW 210 through a plurality of transmission paths 585. The wavelength multiplexer / demultiplexer 249 multiplexes the upstream optical signals of different wavelengths outputted from each of the plurality of transmission paths 585 by the optical SW 210, and outputs them to the transmission path 504 connected to any other ground. In addition, the wavelength multiplexer / demultiplexer 249 demultiplexes the downstream optical signals inputted from other grounds via the transmission path 504 according to the wavelength. The wavelength multiplexer / demultiplexer 249 inputs the demultiplexed downstream optical signals to the optical SW 210 via the plurality of transmission paths 585, respectively, and the plurality of transmission paths 585 are connected to the upstream ports corresponding to the wavelengths of the optical signals.

[0200] The branching unit 253 includes a power splitter 254. The power splitter 254 splits the uplink optical signal and the downlink optical signal transmitted in the transmission path 504. The power splitter 254 inputs the branched uplink optical signal to the port of the optical SW 210 via the transmission path 586, and inputs the branched downlink optical signal to the port of the optical SW 210 via the transmission path 587. The optical SW 210 outputs the optical signal input from the port connected to the transmission path 586 or the transmission path 587 to the port connected to the transmission path 560.

[0201] The wavelength multiplexer / demultiplexer 238 is connected to the optical SW 210 via the transmission path 534, and is connected to the control device 235 via the transmission path 531 and the transmission path 533. The wavelength multiplexer / demultiplexer 238 separates the input optical signal into an uplink optical signal and a downlink optical signal according to the wavelength. The wavelength multiplexer / demultiplexer 238 outputs the uplink optical signal input from the optical SW 210 via the transmission path 534 to the control device 235 via the transmission path 531. The wavelength multiplexer / demultiplexer 238 outputs the downlink optical signal input from the control device 235 via the transmission path 533 to the optical SW 210 via the transmission path 534.

[0202] As described above, the optical GW 2011 is configured without a wavelength multiplexer / demultiplexer between the optical SW 210 and the subscriber device 40, and does not separate the uplink signal from the downlink signal. This can greatly reduce the number of ports used in the optical SW 210 and greatly reduce the amount of information to be managed. Fig.45 As shown, the portion for separating the optical signal to the monitoring device 265 is set to Fig.35 The structure shown.

[0203] Fig.45 1 is a diagram showing a configuration example of the optical access system 112 according to the present embodiment. Fig.45 The optical GW 2012 of the optical access system 112 shown in the figure has a branching unit 255, which replaces Fig.44 The optical GW 2011 shown in FIG. 2011 includes a branching unit 253. The branching unit 255 includes a wavelength multiplexer / demultiplexer 256, a wavelength multiplexer / demultiplexer 257, a power splitter 258, and a power splitter 259.

[0204] The wavelength multiplexer / demultiplexer 256 separates the input optical signal into an uplink optical signal and a downlink optical signal according to the wavelength. The wavelength multiplexer / demultiplexer 256 outputs the uplink optical signal input from the wavelength multiplexer / demultiplexer 249 to the wavelength multiplexer / demultiplexer 257 via the transmission path 588. The wavelength multiplexer / demultiplexer 256 outputs the downlink optical signal input from the wavelength multiplexer / demultiplexer 257 via the transmission path 589 to the wavelength multiplexer / demultiplexer 249.

[0205] The wavelength multiplexer / demultiplexer 257 separates the optical signal into an upstream optical signal and a downstream optical signal according to the wavelength. The wavelength multiplexer / demultiplexer 257 outputs the upstream optical signal input from the wavelength multiplexer / demultiplexer 256 via the transmission path 588 to the transmission path 504. The wavelength multiplexer / demultiplexer 257 inputs the downstream optical signal received from other ground via the transmission path 504 to the wavelength multiplexer / demultiplexer 256 via the transmission path 589.

[0206] The power splitter 258 branches the uplink optical signal transmitted in the transmission path 588, and inputs it to the port of the optical SW 210 via the transmission path 586. The power splitter 259 branches the downlink optical signal transmitted in the transmission path 589, and inputs it to the port of the optical SW 210 via the transmission path 587. The optical SW 210 outputs the optical signal input from the port connected to the transmission path 586 or the transmission path 587 to the port connected to the transmission path 560.

[0207] Although Fig.44 The optical GW2011 shown performs wavelength division multiplexing, but it can also be Fig.46 As shown, the structure is such that the signals transmitted to the respective central offices (ground B and ground C) are not wavelength-division-multiplexed but are transmitted through separate transmission paths.

[0208] Fig.46 This is a diagram showing a configuration example of the optical access system 113 . Fig.46 The optical access system 113 shown is Fig.34The optical access system 101 shown in the figure is different in that it is provided with an optical GW 2013 instead of the optical GW 201. The optical GW 2013 is different from the optical GW 201 in that it does not have the wavelength multiplexer / demultiplexer 220 and the wavelength multiplexer / demultiplexer 243; and it is provided with a control device 230 and a monitoring device 260 instead of a control device 230 and a monitoring device 260. Fig.44 The control device 235, wavelength multiplexer / demultiplexer 238 and monitoring device 265 are shown. The port of the optical SW 210 connected to the transmission path 503 outputs an upstream optical signal and inputs a downstream optical signal.

[0209] In addition, the branch portion 250a may be set as Fig.47 The structure shown. Fig.47 This is a diagram showing a configuration example of the optical access system 114 . Fig.47 The optical GW 2014 of the optical access system 114 shown in FIG. Fig.45 The branch portion 255 has the same structure as shown, but instead of Fig.46 The optical GW 2013 shown has a branching unit 250a.

[0210] (Fifth Embodiment) This embodiment can realize control of a subscriber device in communication. The following description will focus on the differences from the above-mentioned embodiment.

[0211] Fig.48 This is a diagram showing a configuration example of the optical access system 115 . Fig.48 The optical access system 115 shown is Fig.37 The optical access system 104 shown is different in that an optical GW 2015 is provided instead of the optical GW 204. The optical GW 2015 is different from the optical GW 204 in that a monitoring control device 267 is connected to the optical SW 211 instead of the monitoring device 265.

[0212] The monitoring control device 267 includes a wavelength variable receiver 268 and a wavelength variable transmitter 269. The monitoring control device 267 can receive an optical signal of an arbitrary wavelength through the wavelength variable receiver 268, and can transmit an optical signal of an arbitrary wavelength through the wavelength variable transmitter 269. In addition, the optical GW 2015 includes a control device 235. As described in the first embodiment, when the optical GW 2015 is connected to the subscriber device 40, it uses the control device 235 to perform connection processing (registration, wavelength allocation, etc.) of the subscriber device 40 and starts normal communication.

[0213] Here, consider the state where the subscriber device 40-1 is connected to the ground B. Since the subscriber device 40-1 is in a state of performing normal communication, it cannot communicate with the control device 235. Therefore, by providing the monitoring control device 267 connected to the optical SW 211 as a small optical SW, it is possible not only to monitor the communication state of the subscriber device 40-1, but also to implement instructions for various settings of the subscriber device 40-1. That is, the optical signal separated by the power splitter 251 is output to the optical SW 211 via the transmission path 555. The optical SW 211 outputs the received optical signal to the monitoring control device 267. The monitoring control device 267 monitors the optical signal received from the optical SW 211 through the variable wavelength receiver 268, and further receives the control signal superimposed on the received optical signal. The variable wavelength transmitter 269 of the monitoring control device 267 transmits the control signal for the subscriber device 40 through the optical signal. The optical SW 211 outputs the signal received from the variable wavelength transmitter 269 to the port corresponding to the wavelength. The power splitter 251 multiplexes the control signal received from the optical SW 211 via the transmission path 556 with the optical signal transmitted in the transmission path 512. With this configuration, even when the subscriber device 40-1 is performing normal communication, a request for changing the connection destination can be received from the subscriber device 40-1, and a control signal can be sent to perform wavelength switching on the subscriber device 40-1.

[0214] In the communication of control signals between the monitoring control device 267 and each subscriber device 40, a control signal is used which is slower than the optical main signal between the subscriber devices and can be superimposed on the main signal. For example, a technique such as AMCC can be used.

[0215] (Sixth Embodiment) This embodiment electrically processes the optical signal extracted from the light SW. Hereinafter, the differences from the above-mentioned embodiment will be mainly described.

[0216] Fig.49 This is a diagram showing a configuration example of the optical access system 116 . Fig.49 The optical access system 116 shown is Fig.38 The optical access system 105 shown is different in that an optical GW 2016 is provided instead of the optical GW 202. The optical GW 2016 is different from the optical GW 202 in that an electrical processing unit 600 is connected.

[0217] The electrical processing unit 600 converts the optical signal into an electrical signal and performs electrical processing, and then converts the optical signal into an optical signal again and outputs the optical signal. The electrical processing unit 600 includes an O / E conversion unit 610, a processing execution unit 620, and an E / O conversion unit 630. The O / E conversion unit 610 corresponds to Fig.13The O / E conversion unit 610 converts the optical signal input from the optical SW 210 into an electrical signal and outputs the electrical signal to the processing execution unit 620. The processing execution unit 620 corresponds to Fig.13 The processing execution unit 86 and the storage unit 88 are connected. In the processing execution unit 620, a processor such as a CPU or an accelerator reads a program from a storage unit (not shown) and executes it, thereby performing electrical processing on the electrical signal converted by the O / E conversion unit 610. In this electrical processing, functions such as signal processing functions using electricity and OLT are realized. Signal processing functions are, for example, code error correction such as FEC. The E / O conversion unit 630 corresponds to Fig.13 The E / O conversion unit 87 converts the electrical signal into an optical signal and outputs it to the optical SW 210. The O / E conversion unit 610 and the E / O conversion unit 630 are, for example, variable wavelength transceivers.

[0218] exist Fig.49 In the example, the subscriber device 40-M is an ONU of a PON (Passive Optical Network). The subscriber device 40-M is connected to the optical GW 2016 via a transmission path 501 such as an optical fiber and a power splitter 507. In the processing execution unit 620 of the electrical processing unit 600, error correction functions, OLT functions, etc. are implemented.

[0219] The wavelength control unit 310 notifies the processing execution unit 620 of the determination condition for determining the signal to be electrically processed and the type of electrical processing to be performed on the signal. The processing execution unit 620 stores the determination condition and the type of electrical processing notified from the wavelength control unit 310.

[0220] For example, in Fig.33 In step S5, the wavelength control unit 310 determines whether to perform electrical processing in the communication between the subscriber device 40 of the transmission source of the connection request (hereinafter, recorded as the request source subscriber device 40) and the communication destination subscriber device 40. The wavelength control unit 310 determines whether to perform electrical processing and what kind of electrical processing to perform if it is performed, based on the relative distance between the request source subscriber device 40 and the communication destination subscriber device 40, the service provided to the request source subscriber device 40 or the communication destination subscriber device 40, etc. In the case where it is determined that the signal sent from the request source subscriber device 40 to the communication destination subscriber device 40 is electrically processed (hereinafter, the transmission signal electrical processing), the wavelength control unit 310 allocates the first transmission wavelength and the second transmission wavelength from the idle wavelengths. In addition, in the case where it is determined that the signal sent from the communication destination subscriber device 40 to the request source subscriber device 40 is electrically processed (hereinafter, the reception signal electrical processing), the wavelength control unit 310 allocates the first reception wavelength and the second reception wavelength from the idle wavelengths.

[0221] The first transmission wavelength is a wavelength for routing an optical transmission signal, which is an optical signal transmitted from the request source subscriber device 40 to the communication destination subscriber device 40, to the electrical processing unit 600. The second transmission wavelength is a wavelength for routing a transmission signal, which is an optical signal transmitted from the communication destination subscriber device 40 to the communication destination subscriber device 40, to the port corresponding to the communication destination subscriber device 40. The first reception wavelength is a wavelength for routing a reception signal, which is an optical signal transmitted from the communication destination subscriber device 40 to the request source subscriber device 40, to the electrical processing unit 600. The second reception wavelength is a wavelength for routing a reception signal, which is an optical signal transmitted from the communication destination subscriber device 40 to the request source subscriber device 40, to the port corresponding to the request source subscriber device 40. The first transmission wavelength and the second transmission wavelength may be the same wavelength, and the first reception wavelength and the second reception wavelength may be the same wavelength.

[0222] When it is determined that the transmission signal is to be processed electrically, the wavelength control unit 310 sets the information of the first transmission wavelength as the transmission wavelength in the wavelength instruction sent to the request source subscriber device 40. In addition, when it is determined that the reception signal is to be processed electrically, the wavelength control unit 310 sets the information of the second reception wavelength as the reception wavelength in the wavelength instruction sent to the request source subscriber device 40.

[0223] When it is determined that the transmission signal is to be processed electrically, the OPS 300 instructs the second transmission wavelength to be used as the reception wavelength of the communication destination subscriber device 40. When it is determined that the reception signal is to be processed electrically, the OPS 300 instructs the first transmission wavelength to be used as the transmission wavelength of the communication destination subscriber device 40. For example, in the optical GW control unit 301 that controls the optical GW 200 that accommodates the communication destination subscriber device 40, the wavelength control unit 310 instructs the control device 230 to transmit the wavelength instruction that sets the reception wavelength and the transmission wavelength of the communication destination subscriber device 40.

[0224] Furthermore, when it is determined that the transmission signal electrical processing is to be performed, the wavelength control unit 310 generates first instruction information that associates the determination condition for determining the transmission signal transmitted from the request source subscriber device 40 to the communication destination subscriber device 40, the type of transmission signal electrical processing to be performed on the transmission signal, the first transmission wavelength, and the second transmission wavelength. Furthermore, when it is determined that the reception signal electrical processing is to be performed, the wavelength control unit 310 generates second instruction information that associates the determination condition for determining the reception signal transmitted from the communication destination subscriber device 40 to the request source subscriber device 40, the type of reception signal electrical processing to be performed on the reception signal, the first reception wavelength, and the second reception wavelength. The wavelength control unit 310 transmits an electrical processing execution instruction that sets the generated first instruction information and the second instruction information to the electrical processing unit 600.

[0225] When performing electrical processing of a transmission signal, the optical SW control section 320 controls the optical SW 210 so that the transmission signal of the first transmission wavelength transmitted by the request source subscriber device 40 is output to the electrical processing section 600, and the transmission signal of the second transmission wavelength input from the electrical processing section 600 is output to the transmission path 541 corresponding to the communication destination subscriber device 40. Furthermore, when performing electrical processing of a reception signal, the optical SW control section 320 controls the optical SW 210 so that the reception signal of the first transmission wavelength input from the transmission path 542 corresponding to the communication destination subscriber device 40 is output to the electrical processing section 600, and the reception signal of the second transmission wavelength input from the electrical processing section 600 is output to the transmission path 522 corresponding to the request source subscriber device 40.

[0226] For example, it is assumed that the transmission signal electrical processing and the reception signal electrical processing are performed on the optical signal between the subscriber device 40-2 and the communication destination subscriber device 40 of the ground C. The transmission signal of the first transmission wavelength transmitted by the subscriber device 40-2 is output to the electrical processing unit 600 via the optical SW210. The O / E conversion unit 610 converts the transmission signal input from the optical SW210 into an electrical signal. The processing execution unit 620 refers to the prescribed information included in the transmission signal converted into the electrical signal, and when it is determined that the determination condition included in the first instruction information is satisfied, the transmission signal is subjected to the transmission signal electrical processing corresponding to the determination condition. For example, the processing execution unit 620 performs error correction such as FEC (forward error correction). The E / O conversion unit 630 converts the transmission signal of the electrical signal after the error correction by the processing execution unit 620 into an optical signal of the second transmission wavelength indicated by the first instruction information, and outputs it to the optical SW210. The optical SW210 outputs the transmission signal of the second transmission wavelength to the transmission path 541 corresponding to the ground C. By performing error correction, transmission characteristics are improved.

[0227] The optical SW 210 outputs the reception signal of the first reception wavelength input from the transmission path 542 corresponding to the communication destination subscriber device 40 to the ground C to the electrical processing unit 600. The O / E conversion unit 610 converts the reception signal input from the optical SW 210 into an electrical signal. The processing execution unit 620 refers to the prescribed information included in the transmission signal converted into the electrical signal, and when it is determined that the determination condition included in the second instruction information is satisfied, performs reception signal electrical processing corresponding to the determination condition on the reception signal. The E / O conversion unit 630 converts the reception signal of the electrical signal subjected to the reception signal electrical processing by the processing execution unit 620 into an optical signal of the second reception wavelength indicated by the second instruction information, and outputs it to the optical SW 210. The optical SW 210 outputs the transmission signal of the second reception wavelength to the transmission path 522 corresponding to the subscriber device 40-2.

[0228] Fig.50 1 is a diagram showing a configuration example of the optical access system 116 when the electrical processing unit 600 performs signal multiplexing. The electrical processing unit 600 includes O / E converters 610 - 1 and 610 - 2 as a plurality of O / E converters 610 .

[0229] The uplink optical signal of the subscriber device 40-3 and the uplink optical signal of the subscriber device 40-M are connected to the electrical processing unit 600 via the optical SW 210. The OLT function is installed in the electrical processing unit 600. The processing execution unit 620 of the electrical processing unit 600 performs the processing of the electrical part of the OLT function. A plurality of subscriber devices 40 are connected to the OLT. The processing execution unit 620 installed with the OLT function manages these subscriber devices 40 in a unified manner.

[0230] The O / E conversion unit 610-1 converts the uplink optical signal of the subscriber device 40-3 input from the optical SW 210 into an electrical signal, and outputs it to the processing execution unit 620. The O / E conversion unit 610-2 converts the uplink optical signal of the subscriber device 40-M input from the optical SW 210 into an electrical signal, and outputs it to the processing execution unit 620. The processing execution unit 620 collects the uplink electrical signals sent from the subscriber device 40-3 and the subscriber device 40-M into one, and outputs it to the E / O conversion unit 630. The E / O conversion unit 630 converts the uplink electrical signal output from the processing execution unit 620 into an optical signal according to the wavelength instructed by the control device 230, and outputs it to the optical SW 210. The optical SW 210 outputs the uplink optical signal input from the electrical processing unit 600 to the transmission path 541 corresponding to the ground C. In this way, the electrical processing unit 600 receives the multiple optical signals branched by the optical GW 2016, converts them into electrical signals, multiplexes the same signals to the destination through the multiplexing circuit, and then converts them into optical signals again and sends them to the optical GW 2016. This can increase the transmission speed. Fig.49 and Fig.50 This is an example in which one electrical processing unit is provided, but a configuration having a plurality of electrical processing units may also be employed.

[0231] The power splitter 507 between the subscriber device 40 and the optical GW 2016 may also be a wavelength multiplexer / demultiplexer. For example, when the optical access system 116 is a WDM-PON, a wavelength demultiplexer is used between the subscriber device 40 and the optical GW 2016.

[0232] (Seventh Embodiment) This embodiment is a method of connecting optical SWs of different grounds in a ring shape. The following description will focus on the differences from the above-mentioned embodiment.

[0233] Fig.51 1 is a diagram showing a configuration example of an optical access system 117. The optical access system 117 is a configuration in which three or more different ground optical switches 212 are connected in a ring shape via an optical communication network 30. Fig.51 In the example shown, the optical access system 117 is a structure in which the optical SW212a as the optical SW212 for the ground A, the optical SW212b as the optical SW212 for the ground B, and the optical SW212c as the optical SW212 for the ground C are connected in a ring. The path between the optical SW212a and the optical SW212b in the optical communication network 30 is recorded as a path P31, the path between the optical SW212b and the optical SW212c in the optical communication network 30 is recorded as a path P32, and the path between the optical SW212c and the optical SW212a in the optical communication network 30 is recorded as a path P33. In addition, one or more subscriber devices 40a are connected to the optical SW212a, one or more subscriber devices 40b are connected to the optical SW212b, and one or more subscriber devices 40c are connected to the optical SW212c.

[0234] As the light SW 212, the light SW or light GW of the above-mentioned embodiment is used. Figure 6 to Figure 10 , Fig. 27 , Figure 34 to Figure 50 The ground B in is set as Fig.51 The left-handed direction in the ring shown will Figure 6 to Figure 10 , Fig. 27 , Figure 34 to Figure 50 The ground C in is set to Fig.51In the right-handed loop shown in FIG. 1 , the light SW212a from ground A to the light SW212b from ground B is connected via path P31, and the light SW212b from ground B to the light SW212a from ground A is connected via path P32, the light SW212-c from ground C, and path P33. In addition, the light SW212a from ground A to the light SW212c from ground C is connected via path P33, and the light SW212c from ground C to the light SW212a from ground A is connected via path P32, the light SW212b from ground B, and path P31.

[0235] Therefore, with the left-rotating connection from the light SW212a for ground A to the light SW212b for ground B as a backup system, a connection obtained through a right-rotating path connecting from the light SW212a for ground A to the light SW212b for ground B via the light SW212c for ground C is also possible, and its reverse rotation is also possible. Similarly, with the right-rotating connection from the light SW212a for ground A to the light SW212c for ground C as a backup system, a connection obtained through a left-rotating path connecting from the light SW212-a for ground A to the light SW212c for ground C via the light SW212b for ground B is also possible, and its reverse rotation is also possible.

[0236] In addition, as a backup system for connecting subscriber devices 40a connected to optical SW212a to ground A, a left-rotating path via path P31, optical SW212b to ground B, path P32, optical SW212c to ground C, and path P33, or a left-rotating path via path P33, optical SW212c to ground C, path P32, optical SW212b to ground B, and path P31 can be used.

[0237] For example, in Fig.14 In the example, the middle distance line P2 can be set as a circular left-handed path, and the middle distance line P3 can be set as a circular right-handed path. Fig.15 , Fig.18 Any one of the ground pairs #1 to #q is set as a circular left-hand ground pair, and the other one is set as a circular right-hand ground pair. Fig.25 , Fig.26 In the case of an optical SW 1010 in an optical GW, any one of the uplinks #11 to #43 can be set as a circular left-handed path, and the other can be set as a circular right-handed path. Here, the path not selected as the circular path can be set as a circular path in the same manner as the path selected as the circular path, or can be a slanted line other than a circular path, can be connected to the subscriber device 40, or can be connected to the subscriber device 40. Fig.25 , Fig.26Other light SW1010 connections are shown.

[0238] (Eighth Embodiment) The optical access system of this embodiment has a function of stopping the connection from the subscriber device to the optical GW. In the optical access system, this function is realized by providing a shutter unit between the subscriber device and the optical SW of the optical GW, and the shutter unit switches whether to input the optical signal sent from the subscriber device to the optical SW or cut it off. As a result, the optical GW receives the optical signal from the subscriber device whose communication is permitted, and does not receive the optical signal from the subscriber device whose communication is not permitted.

[0239] Fig.52 It is a structural diagram of the optical access system 118. Fig.52 The optical access system 118 shown includes a control unit 302 and an optical GW 2018. The optical GW 2018 includes an optical SW 213, a shutter 591, and a WDM device 80.

[0240] The control unit 302 is the control unit 20 or the OSP 300 in the above-mentioned embodiment. The control unit 302 includes a wavelength management control unit 335 and an optical SW control unit 336. When the control unit 302 is the control unit 20 in the above-mentioned embodiment, the wavelength management control unit 335 is the wavelength management control unit 25 in the above-mentioned embodiment, and the optical SW control unit 336 is the optical SW control unit 26 in the above-mentioned embodiment. When the control unit 302 is the OSP 300 in the above-mentioned embodiment, the wavelength management control unit 335 is the wavelength control unit 310 and the control device 230 or the control device 235 in the above-mentioned embodiment, and the optical SW control unit 336 is the optical SW control unit 320 in the above-mentioned embodiment.

[0241] As the optical SW213, the optical SW of the above-mentioned embodiment is used. The optical SW213 has ports 11-1-1 to 11-1-P (P is an integer greater than or equal to 2) and ports 11-2-1 to 11-2-Q (Q is an integer greater than or equal to 2). Port 11-1-p (p is an integer greater than or equal to 1 and less than or equal to P) is connected to the subscriber device 40 via a transmission path 50-1-p. The subscriber device 40 connected to the port 11-1-p is recorded as a subscriber device 40-p. In addition, the port 11-2-1 is connected to the wavelength management control unit 335. Ports 11-2-2, 11-2-3, 11-2-4, 11-2-5, ... are respectively connected to the WDM device 80 via a transmission path. The WDM device 80 multiplexes the optical signals of different wavelengths outputted from the ports 11-2-2, 11-2-3, 11-2-4, 11-2-5, ... of the optical SW213, and outputs the multiplexed signals to the multiplexed communication transmission path 90. In addition, the WDM device 80 demultiplexes the optical signals received via the multiplexed communication transmission path 90 according to the wavelength, and inputs the demultiplexed optical signals to the ports 11-2-2, 11-2-3, 11-2-4, 11-2-5, ... of the optical SW213, respectively. In addition, the optical GW2018 may not be provided with the WDM device 80, and the ports 11-2-2, 11-2-3, 11-2-4, 11-2-5, ... of the optical SW213 may be connected to the subscriber device 40 or the upper network, respectively, via the transmission path 50-2.

[0242] use Fig.52 The function of passing and cutting off the optical signal in the optical GW 2018 is explained. A wavelength corresponding to the communication destination is allocated to each of the multiple subscriber devices 40 connected to the optical GW 2018. For example, a separate wavelength is allocated to each of the multiple subscriber devices 40 connected to the optical GW 2018. On the other hand, sometimes a subscriber device 40 that is not permitted to be connected to the optical GW 2018 is connected to the network by a malicious user, etc. In this case, it is considered that the optical signal of the subscriber device 40 that is not permitted to be connected conflicts with the optical signal of other subscriber devices 40, etc., which has a bad influence on the communication. Therefore, a shutter 591 is set between the subscriber device 40 and the optical SW213 in the optical GW 2018. Fig.52 In FIG. 1 , the shutter 591 provided in the transmission path 50 - 1 - p between the subscriber device 40 - p and the port 11 - 1 - p of the optical SW 213 is described as a shutter 591 - p.

[0243] The shutter 591 is an example of a shutter unit that switches whether to input the optical signal sent from the subscriber device 40 to the optical SW 213 or to cut it off. As long as it can physically pass light or cut light off, any device can be used as the shutter 591. For example, an optical shutter such as a wavelength variable filter or a variable optical attenuator can also be used as the shutter 591. By controlling the state of each shutter 591 to pass or cut off, the optical SW 13 can receive only the optical signal from the authorized subscriber device 40. In this way, optical signals from malicious users are prevented.

[0244] Furthermore, consider a case where a new subscriber device 40 is connected to the optical GW 2018. The new subscriber device 40 is initially connected to the wavelength management control unit 335, and the wavelength management control unit 335 allocates a wavelength used for communication with a communication destination to the new subscriber device 40. Therefore, the port 11-2-1 connected to the wavelength management control unit 335 is set as the connection destination of the port 11-1 to which the subscriber device 40 is not connected.

[0245] When a new subscriber device 40 is connected to port 11-1 of optical SW 213, an optical signal of connection request is output to request new registration to optical GW 2018. At this time, when multiple subscriber devices 40 simultaneously output optical signals of connection request of the same wavelength, a signal collision occurs in wavelength management control unit 335.

[0246] exist Fig.52 In the example, the subscriber device 40-1 passes the wavelength λ 1 The optical signal output by the subscriber device 40-1 communicates with the subscriber device 40 at the ground B. 1 The optical signal is input to port 11-1-1 through shutter 591-1. Optical SW 213 outputs the optical signal input from port 11-1-1 to port 11-2-2. WDM device 80 multiplexes the optical signals output from ports 11-2-2, 11-2-3, ..., and outputs them to multiplex communication transmission path 90.

[0247] On the other hand, it is assumed that a new subscriber device 40-2 is connected to the port 11-1-2 of the optical SW 213 via the transmission path 50-1-2, and a new subscriber device 40-3 is connected to the port 11-1-3 of the optical SW 213 via the transmission path 50-1-3. The subscriber device 40-2 and the subscriber device 40-3 transmit a wavelength λ for requesting a new registration. 1 The connection destinations of ports 11-1-2 and 11-1-3 are both port 11-2-1 of the initial value. When subscriber device 40-2 and subscriber device 40-3 simultaneously output wavelength λ 1In the case of an optical signal of a connection request, a signal collision occurs in the wavelength management control unit 335. Due to the occurrence of the signal collision, the registration of the new subscriber device 40-2 and the subscriber device 40-3 fails.

[0248] Therefore, the state of the shutter 591 provided between the subscriber device 40 and the optical SW in the optical GW 2018 is controlled so that only the signal of any of the subscriber devices 40 newly registered with the control section 302 is connected to the wavelength management control section 335 via the optical SW 213. For example, the shutter 591-2 is in a state where the optical signal passes, and the shutter 591-3 is in a state where the optical signal is cut off. Then, after the subscriber device 40-2 switches to the wavelength allocated from the wavelength management control section 335, the shutter 591-3 is changed to a state where the optical signal passes. By doing so, it is possible to avoid the collision of optical signals in the wavelength management control section 335.

[0249] In addition, as described above, regarding the port 11-1 of the optical SW 213, as an initial state, the wavelength management control unit 335 becomes the connection destination. Therefore, if a malicious user connects to the port 11-1 in the initial state, the wavelength management control unit 335 may be attacked. Therefore, by controlling the state of each shutter 591, the port 11-1 in the initial state of the optical SW 213 does not receive an optical signal from an unauthorized subscriber device 40. For example, the shutter 591 corresponding to the registered subscriber device 40 and the shutter 591 corresponding to the newly registered subscriber device 40 are placed in a pass state, and the other shutters 591 are placed in a shielded state. On this basis, the optical SW 213 controls so that the optical signal of the newly registered subscriber device 40 is input from the port 11-1 in the initial state, and the input optical signal is output from the port 11-2-1 to the wavelength management control unit 335. By doing so, it is possible to prevent the optical signal from the malicious user.

[0250] In order to carry out the above control, Fig.53 As shown, a shutter control unit for controlling each shutter may be provided in the control unit. Thus, each shutter can be controlled from the outside.

[0251] Fig.53 is a structural diagram of the optical access system 119. Fig.53 In the optical access system 119 shown in FIG. Fig.52 The same parts as the optical access system 118 are marked with the same reference numerals, and their description is omitted. Fig.52 The optical access system 118 shown in FIG. 1 is different in that it includes a control unit 303 instead of the control unit 302. The control unit 303 is similar to the control unit 302. Fig.52The control unit 302 shown is different in that it further includes a shutter control unit 337. By providing the shutter control unit 337, the shutter 591 can be controlled from the outside.

[0252] The shutter control unit 337 shares various information such as subscriber information with other control function units in the control unit 303. When a new subscriber device 40-p is connected, the shutter control unit 337 controls the shutter 591-p corresponding to the subscriber device 40-p to change from the cut-off state to the pass-through state based on the subscriber information and the like registered in the control unit 303. Thus, when a new subscriber device 40 is connected, the shutter control unit 337 controls the shutter 591 corresponding to the new subscriber device 40 to be in the pass-through state in addition to the shutter 591 corresponding to the registered subscriber device 40, and the other shutters 591 to be in the blocked state.

[0253] In addition, when a plurality of subscriber devices 40 are newly connected to the optical GW 2019 at the same time, the shutter control unit 337 determines the order of these subscriber devices 40 according to the respective priorities of these subscriber devices 40, the distances from these subscriber devices 40 to the optical GW 2019, and the like. For example, if the logical conditions such as the priorities are the same, the shutter control unit 337 determines the order according to the physical conditions such as the distance. The shutter control unit 337 controls in accordance with the determined order so that the states of the shutters 591 corresponding to these subscriber devices 40 are changed from the shielding state to the passing state within a certain period of time. The subscriber device 40 newly connected to the optical GW 2019 continuously outputs the optical signal of the connection request at a certain interval. Thus, the optical signal of the connection request transmitted at the timing when the shutter 591 is in the passing state is output to the wavelength management control unit 335.

[0254] Even when the wavelength management control unit 335 has a wavelength variable selective reception function, if the wavelengths of optical signals outputted from the plurality of subscriber devices 40 newly connected to the optical SW 213 are the same, signal collision occurs in the wavelength management control unit 335. Therefore, the shutter 591 described above is required.

[0255] In addition, a light detection function may be installed in the shutter 591. For example, a light sensor for detecting light may be provided in the shutter 591. The shutter 591 senses the light signal from the subscriber device 40 newly connected to the transmission path 50-1 by the light detection function, and notifies the control unit 302. The shutter 591 may notify the control unit 302 when sensing light with an intensity greater than a predetermined value, or may notify the control unit 302 of information on the intensity of the received light. The light SW control unit 336 of the control unit 302 controls the light SW213 so that the subscriber device 40 corresponding to the shutter 591 and the wavelength management control unit 335 are connected, thereby performing an initial connection operation. Alternatively, the shutter control unit 337 may make the shutter 591 a shielded state when it is determined that the light sensor of the shutter 591 senses an excessively strong signal light, thereby cutting off the light signal as an abnormal signal. The excessively strong signal light refers to, for example, a level that causes damage to components such as the light SW213 or generates signal degradation due to nonlinear optical effects.

[0256] In addition, when a connection of a new subscriber device 40 is detected even though registration information such as subscriber information is not registered in the control unit 302, that is, there is no scheduled connection to the optical GW, the shutter control unit 337 can determine that it is a connection by a malicious user, and can take measures such as blocking the shutter 591. For example, information of a newly connected subscriber device 40 is registered in advance in the control unit 302. This information includes information of the port 11-1 corresponding to the newly connected subscriber device 40 and information of the period of the new connection. When the light sensor of the shutter 591-p detects an optical signal, it notifies the control unit 302 of the detection. The shutter control unit 337 specifically specifies the port 11-1-p corresponding to the shutter 591-p of the transmission source of the notification. When the shutter control unit 337 does not have registration information of a subscriber device 40 newly connected to the port 11-1-p at the time of receiving the notification, it determines that it is a connection by a malicious user. In this case, the shutter control unit 337 makes the shutter 591-p of the transmission source of the notification into a blocked state.

[0257] Furthermore, if it is theoretically possible, even if the port 11 - 1 of the optical SW is set to an open state where it is not connected to anywhere, it is possible to cut off the optical signal.

[0258] Light GW2018 and Light GW2019 can also be set Fig.54 Shutter device 592 is shown in place of shutter 591. Fig.541 is a diagram showing a configuration example of a shutter device 592. The shutter device 592 includes a wavelength multiplexer / demultiplexer 593, F shutters 594 (F is an integer greater than or equal to 2), and a wavelength multiplexer / demultiplexer 595. The F shutters 594 are respectively referred to as shutters 594-1 to 594-F. The wavelength multiplexer / demultiplexer 593 demultiplexes the optical signal received from the subscriber device 40 into wavelengths λ 1 ~λ F The shutter 594-f (f is an integer greater than 1 and less than F) transmits or cuts off the wavelength λ separated by the wavelength combiner / demultiplexer 593. f As shutter 594, the same device as shutter 591 can be used. Wavelength multiplexer / demultiplexer 595 multiplexes the optical signals transmitted by shutters 594-1 to 594-F, and outputs the multiplexed signals to optical SW 213.

[0259] Optical signals of more than one desired wavelength can be transmitted or cut off by the shutter device 592. The shutter device 592 needs to be equipped with shutters 594 in the number corresponding to the number of wavelengths used.

[0260] Each shutter 594 may be provided with a light sensing function in the same manner as the shutter 591. When the shutter 594 senses light, it notifies the control unit 302 or the control unit 303 of the light sensing. The light SW control unit 336 specifies the shutter device 592 in which the shutter 594-f of the transmission source of the notification is installed, and the wavelength λ corresponding to the shutter 594-f of the transmission source of the communication. f The wavelength management control unit 335 determines whether to permit the subscriber device 40 connected to the specific shutter device 592 to transmit the specific wavelength λ. f Thus, the wavelength management control unit 335 can sense the signal if the subscriber device 40 outputs an optical signal at an incorrect wavelength. The wavelength management control unit 335 can also send a wavelength setting signal to the subscriber device 40 that outputs an optical signal at an incorrect wavelength again to reset the wavelength.

[0261] On the other hand, the shutter device 592 is also effective when the subscriber device 40 uses a plurality of wavelengths. For example, when the subscriber device 40 uses the wavelength λ 1 and wavelength λ 2 In the case of , the corresponding shutters 594-1 and 594-2 are opened, and the other shutters 594-3 to 594-F are blocked. Thus, it is possible to prevent the inflow of signals of other wavelengths and limit the wavelengths that can be used on the user side. In addition, when the subscriber device 40 starts a new wavelength, such as wavelength λ 3 When the optical signal (optical service) of the new wavelength is used, the corresponding shutter 594-3 is opened. As a result, the subscriber device 40 can start using the optical signal (optical service) of the new wavelength.

[0262] In addition, in Light GW2018 and Light GW2019, you can also set Fig.55 Shutter device 596 is shown in place of shutter 591. Fig.55 596 is a diagram showing a configuration example of a shutter device 596. The shutter device 596 includes a shutter 591, a control wavelength demultiplexer 597, and a shutter controller 598. The control wavelength demultiplexer 597 separates a wavelength λ used in the control of the shutter controller 598 from the signal output from the optical SW 213. c The wavelength λ used in the control of the shutter controller 598 c The optical signal is sent from the control unit 302 or the control unit 303. Wavelength λ c is a wavelength not used in the communication of the subscriber device 40. The wavelength splitter 597 is controlled to separate the wavelength λ c The optical signal of the shutter controller 598 is output to separate the wavelength λ c The remaining optical signal of the optical signal is output to the shutter 591. The shutter controller 598 controls the shutter 591 to be in a transmission state or a shielding state based on the optical signal separated by the wavelength splitter 597.

[0263] In addition, through Fig.52 The optical access system 118 or Fig.53 The optical access system 119 shown is capable of TDM (time division multiplexing) communications. Fig.56 This is a diagram for explaining the operation of the optical access system 118 when performing TDM communication. Fig.56 An example in which a plurality of subscriber devices 40-1 to 40-3 communicate with a subscriber device 40b at a location B will be described.

[0264] exist Fig.56In the example, the subscriber devices 40-1, 40-2, and 40-3 perform TDM communication with the subscriber device 40b connected to another optical GW to the ground, for example, the optical GW to the ground B, via the optical GW 2018. That is, the subscriber device 40b transmits and receives signals to and from the subscriber devices 40-1, 40-2, and 40-3 as burst signals. It is necessary to prevent the optical signals sent from the subscriber devices 40-1, 40-2, and 40-3 to the subscriber device 40b from colliding. Therefore, when the subscriber device 40-1 communicates with the subscriber device 40b, the shutter 591-1 is in the passing state, and the shutters 591-2 and 591-3 are in the shielding state. As a result, the subscriber devices 40-2 and 40-3 cannot communicate with the subscriber device 40b. Next, when the subscriber device 40-2 is communicating with the subscriber device 40b, the shutter 591-2 is in the through state, and the shutters 591-1 and 591-3 are in the shielding state. Thus, the subscriber devices 40-1 and 40-3 cannot communicate with the subscriber device 40b. Next, when the subscriber device 40-3 is communicating with the subscriber device 40b, the shutter 591-3 is in the through state, and the shutters 591-1 and 591-2 are in the shielding state. Thus, the subscriber devices 40-1 and 40-2 cannot communicate with the subscriber device 40b.

[0265] As described above, among the shutters 591 corresponding to the subscriber devices 40 communicating with the same communication destination, the shutters 591 corresponding to the subscriber devices 40 with communication timing are placed in a pass state, and the shutters 591 corresponding to the subscriber devices 40 not with communication timing are placed in a shielded state. Thus, the subscriber devices 40 not with communication timing are placed in a state where they cannot physically communicate. In the case of the optical access system 119, the shutter control unit 337 switches the shielding and passing states of each shutter 591. In addition, when the GW 2018 is equipped with a shutter device 592 instead of the shutter 591, the shielding and passing states of the optical signal of the wavelength used by the subscriber device 40 to communicate with the same communication destination as other subscriber devices 40 are switched. In this way, between the shutter units corresponding to the plurality of subscriber devices 40 with the same communication destination, the time at which the optical signals transmitted from these subscriber devices 40 are transmitted and input to the optical SW 213 is staggered so that they do not overlap. Thus, collision of signals between the subscriber devices 40 is prevented.

[0266] In this embodiment, although the shutter is arranged inside the optical GW as an example of the arrangement location, the shutter may be provided outside the optical GW (for example, between the subscriber device and the optical GW). Alternatively, the shutter may be arranged inside the subscriber device.

[0267] In addition, in this embodiment, the optical access system may also be as follows Fig.57As shown, instead of providing a shutter, the light SW can be controlled so that the optical signal to be cut off is output to a terminal device that terminates the optical signal.

[0268] Fig.57 It is a structural diagram of the optical access system 120. Fig.57 The optical access system 120 shown has a control unit 302 and an optical GW 2020. The optical GW 2020 has an optical SW 213, a WDM device 80, and a non-reflection terminal device 599. The optical GW 2020 may not be provided with the WDM device 80, and the ports 11-2-2, 11-2-3, 11-2-4, 11-2-5, ... of the optical SW 213 are connected to the subscriber device 40 or the upper network via the transmission path 50-2. One or more ports 11-2 of the optical SW 213 are connected to the non-reflection terminal device 599. Fig.57 In FIG. 1 , ports 11-2-(Q-1) and 11-2-Q are connected to a reflectionless termination device 599. The reflectionless termination device 599 terminates the input optical signal and does not output an optical signal.

[0269] When the communication of the subscriber devices 40-2 and 40-3 is not permitted, the optical SW control unit 336 controls the optical SW 2020 so that the optical signal input from the port 11-1-2 is output to the port 11-2-(Q-1), and the optical signal input from the port 11-1-3 is output to the port 1-2-Q. Thus, the optical GW 2020 blocks the optical signal so that the optical signal received from the subscriber devices 40-2 and 40-3 does not affect the communication of other subscriber devices 40.

[0270] In addition, a light sensor having a light detection function may be installed in the port 11-1 on the subscriber device side of the light SW 213, or between the subscriber device 40 and the light SW 213. When the light sensor detects light, it notifies the control unit 302 of the detection. The light SW control unit 336 specifies the port 11-1 where the light sensor of the transmission source of the notification is installed or connected. When the light SW control unit 336 determines that the specified port 11-1 is not the port 11-1 connected to the subscriber device 40 that allows communication, it controls the light SW 213 so that the signal input from the specified port 11-1 is output to the port 11-2 connected to the reflectionless terminal device 599.

[0271] The overlapping of the AMCC signal on the main signal is explained. In the optical domain, the AMCC signal and the main signal use the same wavelength. The main signal is a signal such as a 10Gb / s (gigabit per second) OOK (On-off keying) signal or a CPRI (Common Public Radio Interface) signal. The AMCC signal is transmitted by, for example, overlapping a 1MHz carrier on the main signal and conveying information through intensity modulation. In this way, the low-speed AMCC signal is overlapped on the main signal, and the AMCC signal thus overlapped can be separated from the main signal.

[0272] Furthermore, in the electrical domain, the AMCC signal and the main signal use different frequencies. The AMCC signal is narrower than the main signal. For example, the combiner combines the 10 GHz electrical main signal with the 1 MHz electrical AMCC signal, and the transmitter converts the combined signal into an optical signal, thereby generating a main signal superimposed with the AMCC signal. Furthermore, the carrier frequency can use other frequencies such as 500 kHz that do not overlap with the electrical main signal, and other modulation methods such as phase modulation can also be used for modulation methods.

[0273] The control devices 230, 235, the monitoring devices 260, 265, the monitoring control device 267, the wavelength control unit 310, and the optical SW control unit 320 described above can realize part or all of the functions described above by having a CPU (Central Processing Unit), a memory, an auxiliary storage device, etc. connected via a bus and executing a program. In addition, part or all of the functions of the control devices 230, 235, the monitoring devices 260, 265, the monitoring control device 267, the wavelength control unit 310, and the optical SW control unit 320 can be realized by using hardware such as ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), FPGA (Field Programmable Gate Array). The programs of the control devices 230, 235, the monitoring devices 260, 265, the monitoring control device 267, the wavelength control unit 310, and the optical SW control unit 320 can be recorded in a computer-readable recording medium. The computer-readable recording medium refers to, for example, a removable medium such as a magneto-optical disk, a ROM, or a CD-ROM, or a storage device such as a hard disk built into a computer system. The program can be distributed via a telecommunication line.

[0274] Furthermore, the wavelength control section 310 and the optical SW control section 320 may be implemented using a single information processing device, or may be implemented using a plurality of information processing devices that are communicably connected via a network.

[0275] According to the above-described embodiment, the optical communication device includes an optical SW, a wavelength management control unit, and an optical SW control unit. The optical SW is connected to a plurality of transmission paths, and outputs an optical signal input from any one of the transmission paths to other transmission paths. The wavelength management control unit allocates a wavelength corresponding to a communication destination to a subscriber device. The optical SW control unit controls the optical SW so that an optical signal sent from a subscriber device to which a wavelength is allocated is output to a transmission path corresponding to a forwarding destination on a path from the subscriber device to the communication destination. In this way, the optical SW assigns an output destination of the optical signal by routing. Furthermore, the communication destination refers to, for example, other subscriber devices relative to the subscriber device to which a wavelength is allocated. In addition, the forwarding destination refers to various devices and various functional units on a path from a subscriber device to a relative subscriber device, a control unit, an electrical signal processing unit, a power divider (for example, a coupler), etc.

[0276] The optical SW control unit controls the optical SW so that the optical signal input from the transmission path is output to the transmission path corresponding to the forwarding destination specifically specified by the combination of the subscriber device that sent the optical signal and the wavelength of the optical signal. Alternatively, the optical SW control unit controls the optical SW so that the optical signal is output to the port connected to the transmission path corresponding to the forwarding destination specifically specified by the combination of the subscriber device that sent the optical signal, the wavelength of the input optical signal, and the port to which the optical signal is input. In addition, alternatively, the optical SW control unit controls the optical SW so that the optical signal is output to the following port: only according to the input port, according to the input port and the subscriber device, if the wavelength and the subscriber device are in a unique relationship in the optical SW, the transmission path corresponding to the forwarding destination specifically specified by the combination of the input port and the wavelength is connected.

[0277] According to the above-described embodiment, the transceiver of the subscriber device can be set to use a path corresponding to the destination, and the signal sent from the subscriber device can be relayed according to the destination using the path. Furthermore, after the initial setting of the subscriber device, the optical signal can be relayed according to the destination while reducing the delay compared to the past.

[0278] The embodiments of the present invention have been described in detail above with reference to the drawings, but the specific structure is not limited to these embodiments, and includes designs and the like within the scope that does not depart from the gist of the present invention.

[0279] Description of Reference Numerals 1…Optical communication systems, 10, 10a, 10b, 10c, 10d, 10e, 10f, 10g, 34, 95a-1, 95a-2, 95b-1, 95b-2, 96a-1, 96a-2, 96b-1, 96b-2, 210, 211, 212a, 212b, 212c, 213, 1001, 1002, 1003, 1004, 1005, 1006, 1007, 1008, 1009a, 1009b, 1010-1 to 1010-4 ... optical switches, 11-1, 11-1-1 to 11-1-P, 11-2, 11-2-1 to 11-2-Q…ports, 20, 302, 303…control unit, 21, 41, 411, 412...optical transceiver, 22, 42, 237...optical transmitter, 23, 43, 232, 236... optical receiver, 25, 335…Wavelength Management Control Unit, 26, 320, 336 ... optical SW control unit, 30…Optical communication networks, 31…WDM access ring network, 32-1~32-4…Plug-and-drop nodes, 33…wave division part, 35…combination department, 40, 40-1 to 40-M, 40a-1 to 40a-3, 40b-1 to 40b-3, 40c-1 to 40c-3, 40a-1-1, 40a-1-2, 40-p-1 to 40-p-Np, 40-pN, 40-p to 40-(p+N) ... subscriber device, 46-1, 46-3…User, 46-2…Mobile base station, 50, 50-1, 50-2, 50-1-p~50-1-(p+N), 50-1-p1~50-1-pN, 50-1-p-1~50-p-Np, 50-2-1~50-2-q, 50-2-(N- 1), 50-2-N, 50-2-q-1~50-2-qN, 50-2-(1+N), 53, 54a, 54b, 54c, 54d, 92, 93-1~93-N, 501, 503, 504, 511, 5 12, 521, 522, 531, 533, 534, 540, 541, 542, 543-1, 543-2, 544, 545, 546, 547, 548, 549, 551, 551a, 552, 552b, 555, 560, 561, 562, 563, 570, 571, 572, 573, 574, 575, 581, 582, 583, 584, 585, 586, 587, 588, 589... transmission path, 51, 73…Return transmission path, 55, 55-1, 55-2, 55-p, 55-(p+1), 56, 57a, 57b, 61, 66, 69, 71, 72, 251, 251a, 251b, 252, 252b, 254, 258, 259, 270, 271, 272, 273, 502, 507...power divider, 58, 59…Distribution Department, 60, 65…Monitoring circuit, 67, 68, 80, 80a, 80b, 81, 89, 97…WDM devices, 82a-1, 82a-2, 82b-1, 82b-2, 241, 247…combiner, 83a-1, 83a-2, 83b-1, 83b-2, 242, 248…wave splitter, 85…O / E conversion unit, 86…Processing execution department, 87…E / O conversion unit, 88…Storage department, 90, 91…Multiplexed communication transmission path, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120... optical access system, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2018, 2019, 2020...Optical Gateway, 220, 238, 243, 244, 245, 249, 256, 257, 593, 595… wavelength combiner / demultiplexer, 230…control device, 231, 261…Wavelength splitter, 233, 269… variable wavelength transmitter, 235…control device, 250, 250a, 250b, 253, 255... branch part, 260, 265… monitoring device, 262…optical receiver, 266… Wavelength variable optical receiver, 267…Monitoring and control devices, 268… variable wavelength receiver, 300…operating system, 301 ... optical GW control unit, 310…Wavelength control unit, 337…Shutter control unit, 350…Manage database, 452… variable wavelength filter, 453…Receiver, 454…WDM filter, 591-1~591, 594-1~594-m…Shutter, 592, 596…Shutter device, 597…Controlled wavelength splitter, 598…Shutter controller, 599…Non-reflective terminal device, 84, 600…Electrical Processing Department, 861…processor, 862…Accelerator.

Claims

1. An optical communication device, wherein: have: An optical switch connected to a plurality of transmission paths and outputting an optical signal input from any one of the transmission paths to the other transmission paths; a wavelength management control unit that allocates a wavelength corresponding to a communication destination to a subscriber device; as well as The optical switch control unit controls the optical switch so that the optical signal transmitted from the subscriber device to which the wavelength is allocated is output to a transmission path corresponding to a forwarding destination on a path to the communication destination.

2. An optical communication device, wherein: have: An optical switch connected to a plurality of transmission paths and outputting an optical signal input from any one of the transmission paths to the other transmission paths; a wavelength management control unit that dynamically allocates a wavelength corresponding to a communication destination to a subscriber device; as well as An optical switch control unit controls the optical switch so that an optical signal input from the transmission path is output to the transmission path corresponding to a communication destination specified by a combination of the subscriber device that transmits the input optical signal and a wavelength of the input optical signal.

3. The optical communication device according to claim 1 or 2, wherein: The wavelength management control unit receives a request for wavelength allocation via an optical signal and performs a wavelength allocation process in which a wavelength corresponding to a communication destination is dynamically allocated to a subscriber device that has sent the request and the allocated wavelength is notified to the subscriber device via an optical signal. The optical switch control unit controls the optical switch so that optical signals are transmitted and received between the subscriber device and the wavelength management control unit while the wavelength assignment process is being executed.

4. The optical communication device according to claim 3, wherein: The optical signal transmitted and received between the wavelength management control unit and the subscriber device is at a lower speed than a main signal which is an optical signal between subscriber devices.

5. The optical communication device according to any one of claims 1 to 4, wherein: The optical switch has a plurality of first ports and a plurality of second ports respectively connected to different transmission paths, and outputs optical signals input from the first ports to the second ports, and outputs optical signals input from the second ports to the first ports.

6. The optical communication device according to claim 5, wherein: The optical switch is connected to a transmission path that inputs an optical signal output from the second port to another second port.

7. The optical communication device according to claim 5, wherein: The optical switch is connected to one or both of a first distribution unit and a second distribution unit, the first distribution unit distributes the optical signal output from the second port into multiple signals and inputs the distributed multiple optical signals to different first ports respectively, and the second distribution unit distributes the optical signal output from the first port into multiple signals and inputs the distributed multiple optical signals to different second ports respectively.

8. The optical communication device according to any one of claims 1 to 7, wherein: A monitoring unit is further provided for monitoring the optical signal transmitted through the transmission path.

9. The optical communication device according to any one of claims 1 to 7, wherein: The wavelength management control unit performs a wavelength change process to instruct the subscriber device to change the wavelength. During the wavelength change process, the optical switch control unit controls the optical switch so that an optical signal is received and transmitted between the subscriber device and the wavelength management control unit. After the wavelength change process, when an optical signal of a changed wavelength is input from the subscriber device, the optical switch is controlled so that the input optical signal is output to the transmission path corresponding to the communication destination.

10. The optical communication device according to claim 9, wherein: further comprising a monitoring unit configured to monitor an optical signal transmitted in the transmission path, The wavelength management control unit performs the wavelength change process on the subscriber device based on information generated by the monitoring of the monitoring unit.

11. The optical communication device according to claim 9 or 10, wherein: The wavelength management control unit receives a wavelength change request from the subscriber device and performs the wavelength change process.

12. The optical communication device according to any one of claims 5 to 7, wherein: The optical switch is connected to one or more wave combining devices and one or more wave splitting devices. The combining device combines the optical signals of different wavelengths output from the plurality of the second ports and outputs the combined signals to a multiplexed communication transmission path. The demultiplexing device demultiplexes the optical signal received via the multiplexed communication transmission path according to the wavelength, and inputs the demultiplexed optical signal to the plurality of second ports respectively.

13. The optical communication device according to claim 12, wherein: A monitoring unit is further provided for monitoring the optical signal transmitted in the multiplexed communication transmission path.

14. The optical communication device according to claim 12, wherein: The wavelength management control unit performs a wavelength change process to instruct the subscriber device to change the wavelength. During the wavelength change process, the optical switch control unit controls the optical switch so that an optical signal is received and transmitted between the subscriber device and the wavelength management control unit. After the wavelength change process, when an optical signal of a changed wavelength is input from the subscriber device, the optical switch is controlled so that the input optical signal is output to the transmission path corresponding to the communication destination.

15. The optical communication device according to claim 14, wherein: further comprising a monitoring unit configured to monitor an optical signal transmitted in the multiplexed communication transmission path, The wavelength management control unit performs the wavelength change process on the subscriber device based on information generated by the monitoring of the monitoring unit.

16. The optical communication device according to claim 14 or 15, wherein: The wavelength management control unit receives a wavelength change request from the subscriber device and performs the wavelength change process.

17. The optical communication device according to any one of claims 1 to 16, wherein: The optical switch is connected to an electrical processing unit, and the electrical processing unit converts the optical signal output by the optical switch into an electrical signal, processes the electrical signal, converts it into an optical signal, and inputs it into the optical switch. The optical switch control unit controls the optical switch so that the optical signal input from the transmission path is output to the electrical processing unit according to a combination of the subscriber device that sends the input optical signal and the wavelength of the input optical signal, and the signal input from the electrical processing unit is output to the transmission path corresponding to the communication destination specifically specified by the wavelength.

18. The optical communication device according to any one of claims 1 to 17, wherein: The optical switch is connected to a part of the plurality of subscriber devices that performs time division multiplexing using optical signals of the same wavelength through the same transmission path.

19. The optical communication device according to claim 18, wherein: The subscriber device bus performing time division multiplexing is connected to the transmission path or is star-connected to a power divider provided in the transmission path.

20. The optical communication device according to any one of claims 1 to 17, wherein: The optical switch is connected to the wavelength combining and decomposing device via a plurality of the transmission paths. The wavelength combining and demultiplexing device performs the following processing: an optical multiplexing signal is input from a multiplexed communication transmission path, and optical signals obtained by demultiplexing the input optical multiplexing signal are input to the optical switch via different transmission paths respectively, wherein the optical multiplexing signal is a signal obtained by multiplexing optical signals sent from a part of the subscriber devices that communicate through wavelength division multiplexing among the plurality of subscriber devices; an optical signal of a different wavelength output by the optical switch is input from each of the plurality of transmission paths, and the input optical signals are combined and output to the multiplexed communication transmission path.

21. The optical communication device according to claim 20, wherein: The subscriber device bus that communicates by wavelength division multiplexing is connected to the multiplexed communication transmission path or is connected in a star shape to a power splitter provided in the multiplexed communication transmission path.

22. The optical communication device according to claim 20, wherein: The wavelength multiplexing / demultiplexing device is connected to a loop type network via the multiplexed communication transmission path, and the subscriber device communicating by wavelength division multiplexing is connected to the loop type network.

23. The optical communication device according to any one of claims 1 to 17, wherein: The optical switch is connected to a loop-type network to which the subscriber devices communicating by wavelength division multiplexing are connected via the transmission path for transmitting an optical signal to the network and the transmission path for receiving an optical signal from the network.

24. The optical communication device according to any one of claims 1 to 23, wherein: A shutter unit is further provided for switching whether to input the optical signal transmitted from the subscriber device to the optical switch or to cut it off.

25. The optical communication device according to claim 24, wherein: The shutter unit switches whether to input the optical signal transmitted from the subscriber device to the optical switch for each wavelength or to cut it off.

26. The optical communication device according to claim 24 or 25, wherein: A plurality of shutter units are provided, each corresponding to different subscriber devices. The shutter portions corresponding to the plurality of subscriber devices having the same communication destination are configured to shift the timing at which the optical signals transmitted from the subscriber devices are transmitted and input to the optical switch.

27. The optical communication device according to any one of claims 24 to 26, wherein: The shutter unit further includes a shutter control unit that controls whether to input an optical signal transmitted from the subscriber device to the optical switch or to cut off the optical signal.

28. The optical communication device according to any one of claims 1 to 23, wherein: The optical switch is connected to a terminal device for terminating light. The optical switch control section controls the optical switch so that an optical signal transmitted from the subscriber device is output to the terminal device.

29. An optical communication system comprising a plurality of subscriber devices and the optical communication device according to any one of claims 1 to 28, wherein: The subscriber device has either or both of the following: an optical transmission unit that transmits an optical signal of a wavelength allocated by the optical communication device; and The optical receiving unit receives an optical signal of a wavelength allocated by the optical communication device.

30. The optical communication system according to claim 29, wherein: The optical communication system comprises a plurality of the optical communication devices. The subscriber device sends or receives an optical signal to or from a communication destination via one or more of the optical communication devices.

31. The optical communication system according to claim 30, wherein: The plurality of optical communication devices are connected in series or in a mesh manner.

32. The optical communication system according to claim 30, wherein: A plurality of the optical communication devices are connected in a ring shape.

33. The optical communication system according to claim 30, wherein: The optical communication system comprises a plurality of the optical communication devices. The optical switch provided in the first optical communication device, namely the first optical switch, is connected to both ends of a first transmission path to which one or more subscriber devices are connected. The optical switch provided in the second optical communication device is connected to both ends of a second transmission path to which one or more subscriber devices are connected. The first optical switch and the second optical switch are connected via a third transmission path and a fourth transmission path, the third transmission path transmits an optical signal from the first optical switch to the second optical switch, and the fourth transmission path transmits an optical signal from the second optical switch to the first optical switch. The first optical switch outputs the optical signal input from the first transmission path to the third transmission path according to the wavelength, and outputs the optical signal input from the fourth transmission path to the first transmission path according to the wavelength, The second optical switch outputs the optical signal input from the second transmission path to the fourth transmission path according to the wavelength, and outputs the optical signal input from the third transmission path to the first transmission path according to the wavelength.

34. An optical communication method, wherein: have: A forwarding step in which an optical switch connected to a plurality of transmission paths outputs an optical signal input from any one of the transmission paths to the other transmission paths; an allocating step, in which the wavelength management control unit allocates a wavelength corresponding to a communication destination to the subscriber device; as well as An optical switch control step in which an optical switch control unit controls the optical switch so that in the forwarding step, the optical signal transmitted from the subscriber device to which the wavelength is allocated is output to a transmission path corresponding to a forwarding destination on a path to the communication destination.

35. An optical communication method, wherein: have: A forwarding step in which an optical switch connected to a plurality of transmission paths outputs an optical signal input from any one of the transmission paths to the other transmission paths; an allocating step in which the wavelength management control unit dynamically allocates a wavelength corresponding to a communication destination to a subscriber device; as well as An optical switch control step, in which the optical switch control unit controls the optical switch so that in the forwarding step, the optical signal input from the transmission path is output to the transmission path corresponding to a communication destination, wherein the communication destination is specifically designated by a combination of the subscriber device that transmits the input optical signal and the wavelength of the input optical signal.

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