Method for transmitting clock information, communication device and optical communication system

Abstract

The invention provides a method for transmitting clock information, which is applied to the field of optical communication. The method for transmitting the clock information comprises the following steps that: source end equipment acquires N pieces of clock information of N paths of service data; the N pieces of clock information are in one-to-one correspondence with the N paths of service data. And the source end device obtains N pieces of first phase discrimination information according to the N pieces of clock information and the clock information of the source end device. The N pieces of first phase discrimination information are in one-to-one correspondence with the N pieces of clock information. And the source end equipment maps the N paths of service data into N first multiframes of the first service frame. The N first multiframes are in one-to-one correspondence with the N paths of service data. The overhead of the N first multiframes carries N pieces of first phase discrimination information. The N first multiframes and the N pieces of first phase discrimination information are in one-to-one correspondence. And the source end equipment maps the first service frame to the first data frame and sends the first data frame. In the technical scheme provided by the invention, the multiple paths of service data and the corresponding multiple pieces of phase discrimination information are transmitted through one service channel, so that communication resources can be saved.

Description

Technical Field

[0001] This application relates to the field of optical communication, and particularly to a method for transmitting clock information, a communication device, and an optical communication system. Background Art

[0002] In the field of optical communication, a client device transmits constant bit rate (CBR) service data to another client device through a node in an optical communication network. For example, nodes in an optical transport network (OTN) include a source device, intermediate nodes, and a sink device. The source device is used to map CBR service data into an OTN frame and transmit the OTN frame to the sink device through an allocated OTN channel. Phase difference information for phase discrimination is carried in the overhead of the OTN frame, and the phase difference information is used to represent the phase difference between the clock information of the source node and the clock information of the CBR service data. The sink device is used to recover the clock information of the client device through the phase difference information for phase discrimination. When the source device needs to transmit multiple CBR service data streams, the source device maps the multiple CBR service data streams into multiple OTN frames and transmits the multiple OTN frames to the sink device through multiple allocated OTN channels. Multiple OTN channels transmit corresponding phase difference information for phase discrimination. At this time, multiple phase difference information for phase discrimination occupies a relatively large amount of communication resources in the optical communication system. Summary of the Invention

[0003] This application provides a method for transmitting clock information, a communication device, and an optical communication system, which can save communication resources by transmitting multiple service data streams and corresponding multiple phase difference information for phase discrimination through one service channel.

[0004] A first aspect of this application provides a method for transmitting clock information. The method for transmitting clock information includes the following steps: The source device obtains N clock information of N service data streams. The N clock information corresponds one-to-one with the N service data streams. N is an integer greater than 1. The source device obtains N first phase difference information for phase discrimination based on the N clock information and the clock information of the source device. The N first phase difference information for phase discrimination corresponds one-to-one with the N clock information. The source device maps the N service data streams into N first multiplex frames of a first service frame. The N first multiplex frames correspond one-to-one with the N service data streams. The N first multiplex frames carry the N first phase difference information for phase discrimination in their overhead. The N first multiplex frames correspond one-to-one with the N first phase difference information for phase discrimination. The source device maps the first service frame into a first data frame and transmits the first data frame.

[0005] In an alternative manner of the first aspect, the phase discrimination information carried in each of the N first complex frames corresponds to the service data. In practical applications, the source device needs to send the first mapping relationship. The first mapping relationship includes the mapping relationship between N paths of service data and N complex frames. If the phase discrimination information carried in each complex frame corresponds to the service data, the sink device can determine the mapping relationship between N phase discrimination information and N complex frames through the first mapping relationship. Therefore, the present application can save transmission resources.

[0006] In an alternative manner of the first aspect, in the first service frame, the first complex frame of the N first complex frames and the next complex frame of the N first complex frames carry the phase discrimination information of the same path of service data. It is defined that the complex frames of the first service frame have a complex frame period of N complex frames. In practical applications, in order to reduce the amount of data to be processed, the source device can continue to carry the phase discrimination information after one or more complex frame periods. For example, the phase discrimination information is carried in the first complex frame period, not carried in the second complex frame period, and carried in the third complex frame period. And so on, the source device periodically carries the phase discrimination information in the complex frame period. The present application can improve the accuracy of the sink device in recovering the clock by carrying the phase discrimination information in each complex frame period. Moreover, in each complex frame period carrying the phase discrimination information, the complex frames at the same position carry the phase discrimination information of the same path of service data. Therefore, the present application can reduce the complexity of processing the phase discrimination information.

[0007] In an alternative manner of the first aspect, the source device obtaining N clock information of N paths of service data includes: the source device obtaining N pulse frequencies of N paths of service data, and the N pulse frequencies correspond to the N paths of service data one by one; the source device obtaining N frequency multiplication coefficients according to the target frequency and the N pulse frequencies, and the N frequency multiplication coefficients correspond to the N pulse frequencies one by one; the source device performing frequency multiplication on the pulse signals of the N paths of service data according to the N frequency multiplication coefficients to obtain N clock information, and the pulse frequencies of the N clock information are the target frequency.

[0008] In an alternative manner of the first aspect, the first service frame carries N frequency multiplication coefficients. The sink device is used to recover the clock information of the client device through the frequency multiplication coefficients and the phase discrimination information. In practical applications, if the pulse frequency of the service data is agreed, the source device can obtain the clock information of the target frequency through the agreed frequency multiplication coefficient and the agreed pulse frequency. At this time, the source device does not need to send the frequency multiplication coefficient. The sink device is used to recover the clock information of the client device through the agreed frequency multiplication coefficient and the phase discrimination information. However, if the pulse frequency of the service data fluctuates or changes, it may cause the sink device to be unable to correctly recover the clock information of the client device. Therefore, by carrying the frequency multiplication coefficients in the first service frame, the present application can improve the accuracy of the sink device in recovering the clock information.

[0009] In an alternative manner of the first aspect, the N first complex frames carry N multiplication factors. The multiplication factor carried by each of the N first complex frames corresponds to the service data. In practical applications, the source device needs to send the first mapping relationship. The first mapping relationship includes the mapping relationship between N service data streams and N complex frames. If the multiplication factor carried by each complex frame corresponds to the service data, the sink device can determine the mapping relationship between the N multiplication factors and the N complex frames through the first mapping relationship. Therefore, the present application can save transmission resources.

[0010] In an alternative manner of the first aspect, the source device multiplies the N service data streams by the N multiplication factors to obtain N clock information, including: the source device multiplies the N service data streams by the N multipliers and the N multiplication factors to obtain N clock information. The N multipliers and the N multiplication factors correspond one by one. The method for transmitting the clock information further includes the following steps: when the pulse frequencies of the N change, the source device modifies the multiplication factors of the N multipliers. In practical applications, the pulse frequency of the service data may fluctuate or change. By adaptively modifying the multiplication factor, the accuracy of the sink device in restoring the clock information can be improved.

[0011] A second aspect of the present application provides a method for transmitting clock information. The method for transmitting clock information includes the following steps: an intermediate node receives a first data frame. The intermediate node demaps the first data frame to obtain a first service frame. The overheads of the N first complex frames of the first service frame carry N first phase discrimination information. The N first complex frames and the N first phase discrimination information correspond one by one. N is an integer greater than 1. The N first complex frames are used to carry N service data streams. The N service data streams and the N first complex frames correspond one by one. The intermediate node obtains N second phase discrimination information based on the N first phase discrimination information and the clock information of the intermediate node. The N first phase discrimination information and the N second phase discrimination information correspond one by one. The intermediate node obtains a second service frame based on the first service frame. The overheads of the N second complex frames of the second service frame carry N second phase discrimination information. The N second complex frames and the N second phase discrimination information correspond one by one. The source device maps the second service frame to a second data frame and sends the second data frame.

[0012] In an alternative manner of the second aspect, the phase discrimination information carried by each of the N second complex frames corresponds to the service data.

[0013] In an alternative manner of the second aspect, in the second service frame, the first complex frame of the N second complex frames and the next complex frame of the N second complex frames carry the phase discrimination information of the same service data stream.

[0014] The third aspect of the present application provides a method for transmitting clock information. The method for transmitting clock information includes the following steps: The sink device receives a second data frame. The sink device demaps the second data frame to obtain a second service frame. The overheads of N second multiplex frames of the second service frame carry N second phase discrimination information. The N second multiplex frames and the N second phase discrimination information are in one-to-one correspondence. N is an integer greater than 1. The N second multiplex frames are used to carry N paths of service data. The N paths of service data and the N second multiplex frames are in one-to-one correspondence. The sink device obtains N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device. The N third phase discrimination information and the N second phase discrimination information are in one-to-one correspondence. The sink device adjusts the clock information of the sink device according to the N third phase discrimination information.

[0015] In an alternative manner of the second aspect, the overheads of N second multiplex frames of the second service frame carry N multiplication factors. The sink device obtaining N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device includes: The sink device multiplies the clock information of the sink device by the N multiplication factors to obtain N target clock information. The N multiplication factors and the N target clock information are in one-to-one correspondence; The sink device performs a difference operation on the N target clock information and the clock information of the sink device to obtain N fourth phase discrimination information. The N fourth phase discrimination information and the N target clock information are in one-to-one correspondence; The sink device performs a phase accumulation operation on the N fourth phase discrimination information and the N second phase discrimination information to obtain N third phase discrimination information.

[0016] The fourth aspect of the present application provides a communication device. The communication device includes a processing module and a transceiver module. The processing module is used to obtain the clock information of N paths of service data. The N clock information and the N paths of service data are in one-to-one correspondence. N is an integer greater than 1. The processing module is further used to obtain N first phase discrimination information based on the N clock information and the clock information of the source device. The N first phase discrimination information and the N clock information are in one-to-one correspondence. The processing module is further used to map the N paths of service data into N first multiplex frames of a first service frame. The N first multiplex frames and the N paths of service data are in one-to-one correspondence. The overheads of the N first multiplex frames carry N first phase discrimination information. The N first multiplex frames and the N first phase discrimination information are in one-to-one correspondence. The processing module is further used to map the first service frame into a first data frame. The transceiver module is further used to send the first data frame.

[0017] In an alternative implementation of the fourth aspect, the processing module is configured to obtain N clock information for N service data streams, including: the processing module is configured to obtain N pulse frequencies of the N service data streams, where the N pulse frequencies correspond one-to-one with the N service data streams; the processing module is configured to obtain N multiplication factors based on a target frequency and the N pulse frequencies, where the N multiplication factors correspond one-to-one with the N pulse frequencies; the processing module is configured to multiply the pulse signals of the N service data streams by the N multiplication factors to obtain N clock information, and the pulse frequencies of the N clock information are the target frequency.

[0018] In an alternative implementation of the fourth aspect, the processing module is configured to multiply the N service data streams by the N multiplication factors to obtain N clock information, including: the processing module is configured to multiply the N service data streams by N multipliers and the N multiplication factors to obtain N clock information, where the N multipliers correspond one-to-one with the N multiplication factors. When the N pulse frequencies change, the processing module is further configured to modify the multiplication factors of the N multipliers.

[0019] The fifth aspect of the present application provides a communication device. The communication device includes a processing module and a transceiver module. The transceiver module is configured to receive a first data frame. The processing module is configured to demap the first data frame to obtain a first service frame. The overheads of N first multiplex frames of the first service frame carry N first phase discrimination information, where the N first multiplex frames correspond one-to-one with the N first phase discrimination information. N is an integer greater than 1. The N first multiplex frames are used to carry N service data streams, where the N service data streams correspond one-to-one with the N first multiplex frames. The processing module is further configured to obtain N second phase discrimination information based on the N first phase discrimination information and the clock information of an intermediate node, where the N first phase discrimination information corresponds one-to-one with the N second phase discrimination information. The processing module is further configured to obtain a second service frame based on the first service frame. The overheads of N second multiplex frames of the second service frame carry N second phase discrimination information, where the N second multiplex frames correspond one-to-one with the N second phase discrimination information. The processing module is further configured to map the second service frame to a second data frame. The transceiver module is further configured to send the second data frame.

[0020] In an alternative implementation of the fifth aspect, the phase discrimination information carried in each of the N second multiplex frames corresponds to the service data.

[0021] In an alternative implementation of the fifth aspect, in the second service frame, the first multiplex frame of the N second multiplex frames and the next multiplex frame of the N second multiplex frames carry the phase discrimination information of the same service data stream.

[0022] The sixth aspect of the present application provides a communication device. The communication device includes a processing module and a transceiver module. The transceiver module is configured to receive a second data frame. The processing module is configured to demap the second data frame to obtain a second service frame. N second phase discrimination information is carried in the overheads of N second complex frames of the second service frame. The N second complex frames and the N second phase discrimination information are in one-to-one correspondence. N is an integer greater than 1. The N second complex frames are used to carry N paths of service data. The N paths of service data and the N second complex frames are in one-to-one correspondence. The processing module is further configured to obtain N third phase discrimination information based on the N second phase discrimination information and the clock information of the destination device. The N third phase discrimination information and the N second phase discrimination information are in one-to-one correspondence. The processing module is further configured to adjust the clock information of the destination device according to the N third phase discrimination information.

[0023] In an optional manner of the sixth aspect, N frequency multiplication coefficients are carried in the overheads of N second complex frames of the second service frame. The processing module obtaining N third phase discrimination information based on the N second phase discrimination information and the clock information of the destination device includes: the processing module multiplying the clock information of the destination device by the N frequency multiplication coefficients to obtain N target clock information, and the N frequency multiplication coefficients and the N target clock information are in one-to-one correspondence; the processing module performing a difference operation on the N target clock information and the clock information of the destination device to obtain N fourth phase discrimination information, and the N fourth phase discrimination information and the N target clock information are in one-to-one correspondence; the processing module performing phase accumulation on the N fourth phase discrimination information and the N second phase discrimination information to obtain N third phase discrimination information.

[0024] It should be understood that there are similarities between the communication device described in the fourth aspect or any optional manner of the fourth aspect and the method for transmitting clock information described in the foregoing first aspect or any optional manner of the first aspect. Therefore, the communication device described in the fourth aspect or any optional manner of the fourth aspect can refer to the method for transmitting clock information described in the foregoing first aspect or any optional manner of the first aspect. Similarly, the communication device described in the fifth aspect or any optional manner of the fifth aspect can refer to the method for transmitting clock information described in the foregoing second aspect or any optional manner of the second aspect. The communication device described in the sixth aspect or any optional manner of the sixth aspect can refer to the method for transmitting clock information described in the foregoing third aspect or any optional manner of the third aspect.

[0025] The seventh aspect of the present application provides an optical communication system. The optical communication system includes the communication device described in the fourth aspect or any optional manner of the fourth aspect, the communication device described in the fifth aspect or any optional manner of the fifth aspect, and the communication device described in the sixth aspect or any optional manner of the sixth aspect.

[0026] The eighth aspect of the present application provides a computer-readable storage medium storing instructions, which, when executed by a computer, implement the method for transmitting clock information in the foregoing first aspect, any optional manner of the first aspect, second aspect, any optional manner of the second aspect, third aspect or any optional manner of the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic structural diagram of an OTN;

[0028] Figure 2 It is a schematic diagram of the processing of the source device transmitting CBR service data provided by the embodiment of the present application;

[0029] Figure 3 It is a first schematic structural diagram of the first service frame provided by the embodiment of the present application;

[0030] Figure 4 It is a schematic diagram of mapping an OSU frame to an OTN frame provided by the embodiment of the present application;

[0031] Figure 5 It is a schematic diagram of the processing of the intermediate node transmitting CBR service data provided by the embodiment of the present application;

[0032] Figure 6 It is a schematic structural diagram of the second service frame provided by the embodiment of the present application;

[0033] Figure 7 It is a schematic diagram of the processing of the sink device transmitting CBR service data provided by the embodiment of the present application;

[0034] Figure 8 It is a schematic structural diagram of the optical communication system provided by the embodiment of the present application;

[0035] Figure 9 It is a second schematic structural diagram of the first service frame provided by the embodiment of the present application;

[0036] Figure 10 It is a third schematic structural diagram of the first service frame provided by the embodiment of the present application;

[0037] Figure 11 It is a schematic flowchart of the method for transmitting clock information provided by the embodiment of the present application;

[0038] Figure 12 It is a first schematic structural diagram of the OTN device provided by the embodiment of the present application;

[0039] Figure 13 It is a second schematic structural diagram of the OTN device provided by the embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] First, some terms in this application are explained to facilitate understanding by those skilled in the art.

[0041] 1) Multiple refers to two or more. "And / or" describes the relationship between related objects, and three types of relationships are possible. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of this application, words such as "first" and "second" are used only for the purpose of distinguishing descriptions and should not be understood to indicate or imply relative importance or order.

[0042] 2) Mapping or multiplexing A into B in this application refers to encapsulating A into B. For example, mapping an optical service unit (OSU) frame into an optical transport network (OTN) frame refers to encapsulating the OSU frame or OSU signal into the OTN frame. Demapping (or demultiplexing) is the inverse process of mapping (or multiplexing).

[0043] 3) Unless otherwise specified, the specific description of some technical features in one embodiment can also be used to explain the corresponding technical features mentioned in other embodiments. For example, the meaning of phase discrimination information in one embodiment can also be applied to the phase discrimination information of the same name mentioned in other embodiments. For another example, the specific examples and descriptions of optical transport network frames can be applied to optical transport network frames mentioned in different specific embodiments or specific examples used to replace optical transport network frames. In addition, in order to more clearly reflect the relationship between components in different embodiments, this application uses the same or similar figure numbers to represent components or method steps with the same or similar functions in different embodiments.

[0044] The embodiments of this application are applicable to optical networks such as optical transport networks (OTNs) or metropolitan area transport networks (MANs). Optical transport networks include OTNs or flexible Ethernet (FlexE). The following description of this application uses OTN as an example. An OTN typically consists of multiple OTN devices connected by optical fibers and can be configured into different topologies, such as linear, ring, and mesh, depending on specific needs. Figure 1 This is a schematic diagram of the structure of an OTN. Figure 1As shown in the figure, the OTN includes a source device 101, a sink device 102, and an intermediate subnet 103. The source device 101 and the sink device 102 are OTN devices. The intermediate subnet 103 includes one or more OTN devices. The source device 101 is connected to the client device 1. The sink device 102 is connected to the client device 2. In practical applications, the client device 1 or the client device 2 can be replaced by a cloud device. The client device 1, the client device 2, and the cloud device can be relay protection devices of the power production network, generating constant bit rate (CBR) service data, such as E1 service (service transmitted by a pulse code modulation (PCM) device through a 2M channel), synchronous digital hierarchy (SDH) service, or any service. The source device 101 maps the client signal generated by the client device 1 into an OTN frame. The OTN frame carries phase discrimination information. The phase discrimination information is used to characterize the phase difference between the clock information of the source device 101 and the clock information of the CBR service data. The OTN frame is transmitted through the intermediate subnet 103 and received by the sink device 102. The sink device 102 is used to recover the clock information of the CBR service data through the phase discrimination information, recover the CBR service data from the OTN frame, and send the CBR service data to the client device 2. The intermediate subnet 103 can be a fgOTN, and the source device 101 and the sink device 102 can be fgOTN devices. The OTN provides multiple fgODUflex transmission paths for the client device, which is equivalent to a dedicated line service.

[0045] According to actual needs, an OTN device may have different functions. Generally, OTN devices are divided into optical layer devices, electrical layer devices, and optoelectronic hybrid devices. Optical layer devices refer to devices that can process optical layer signals, such as optical amplifiers (OAs) and optical add-drop multiplexers (OADMs). The OA is mainly used to amplify optical signals to support longer transmission distances while ensuring specific performance of the optical signals. The OADM is used to perform spatial transformation on optical signals so that they can be output from different output ports (also known as directions). Electrical layer devices refer to devices that can process electrical layer signals, such as devices that can process OTN signals. Optoelectronic hybrid devices refer to devices that have the ability to process both optical layer signals and electrical layer signals. It should be noted that according to specific integration needs, an OTN device can integrate multiple different functions. The technical solution provided in this application is applicable to OTN devices with electrical layer functions in different forms and integration levels.

[0046] It should be noted that the data frame structure used by the optical transmission device in the embodiments of the present application can be an OTN frame, which is used to carry various service data and provide rich management and monitoring functions. The OTN frame can be an optical payload unit (OPU), an optical data unit (ODU), an optical transport unit (OTU), a flexible OTN (FlexO) frame, etc. The OPU includes OPUk, OPUCn, and OPUflex, the ODU includes ODUk, ODUCn, and ODUflex, and the OTU includes OTUk and OTUCn. Among them, the OTU frame includes the ODU frame and OTU overhead, and the ODU frame includes the OPU frame and ODU overhead. k represents different rate levels. For example, k = 1 represents 2.5 Gbps, and k = 4 represents 100 Gbps. Cn represents a variable rate, specifically a rate that is an integer multiple of 100 Gbps. Flex means flexible. It should also be pointed out that with the development of optical transmission network technology, new types of OTN frames may be defined and are also applicable to the present application. For example, the OTN frame can also include an fgOTN frame (including fgODUflex and fgOPUflex) or an optical service unit (OSU) frame. In addition, the method disclosed in the present application can also be applicable to other optical transmission network frames such as FlexE frames.

[0047] In practical applications, when the source device 101 needs to transmit multiple CBR service data, the source device 101 maps the multiple CBR service data into multiple OTN frames and transmits the multiple OTN frames to the sink device 102 through multiple allocated OTN channels. The multiple OTN channels transmit corresponding phase discrimination information. At this time, the multiple phase discrimination information occupies a relatively large amount of communication resources in the optical communication system.

[0048] Therefore, the present application provides an optical communication system. The optical communication system includes a source device, an intermediate node, and a sink device. According to the previous description, the present application describes the methods and systems provided in the present application by taking OTN as an example. At this time, the data frame can be an ODU frame or a multi-frame composed of multiple ODU frames. The service frame can be an OSU frame or a multi-frame composed of multiple OSU frames. The functions of each device in the optical communication system will be described exemplarily below.

[0049] Figure 2 It is a schematic diagram of the processing for the source device provided in the embodiments of the present application to transmit CBR service data. In Figure 2Among them, the thick solid line represents the clock processing flow, and the thin solid line represents the service processing flow. The source device 201 is used to receive N channels of CBR service data from the client device or the cloud device. For example, the source device 201 is connected to N client devices, and the source device 201 receives N channels of CBR service data from the N client devices. The N channels of CBR service data correspond to the N client devices one by one. Another example is that the source device 201 receives N channels of CBR service data from one client device. N is an integer greater than 1. In Figure 2 In the example of, N is equal to 2, and the source device 201 is used to receive CBR1 service data and CBR2 service data. It should be understood that the embodiments of the present application are described by taking CBR service data as an example. In practical applications, the source device 201 can transmit other service data in a similar manner. The source device 201 is used to map N channels of CBR service data to N multiplex frames of the first service frame. The N multiplex frames correspond to the N channels of CBR service data one by one. For example, the source device 201 maps multiple channels of CBR service data to N multiplex frames of the first service frame through the generic mapping procedure (GMP). During this process, the source device is used to achieve service rate adaptation through the local clock of the source device and the service clock of CBR. For example, the source device achieves rate adaptation through a phase-locked loop (PLL). The local clock can also be referred to as the clock information of the source device. During the rate adaptation process, the source device is used to obtain N clock information of N channels of CBR service data. The N clock information corresponds to the N channels of CBR service data one by one. The source device obtains N first phase discrimination information based on the N clock information and the clock information of the source device. The N first phase discrimination information corresponds to the N clock information one by one. The phase discrimination information can also be referred to as the phase demodulation (PD) value. The first phase discrimination information is used to characterize the phase difference between the service clock of CBR and the local clock. The source device adds the N first phase discrimination information to the overhead of the N multiplex frames. The N first multiplex frames correspond to the N first phase discrimination information one by one.

[0050] The source device 201 is used to map the first service frame to the first data frame. For example, the source device 201 maps the first service frame to the first data frame by means of GMP. During the mapping process, the source device 101 first calculates the frame period mapping client signal byte information Cm and the remaining client signal information Cnd through the Cn feedback module. The Cn feedback module can be CnGenPLL. Cm represents the parallelism of the client signal mapping. Cnd represents the number of remaining client signals after mapping the total number of client signals in one frame period according to this parallelism. Cnd and Cm can characterize the overhead fields of the rate ratio between the first service frame and the first data frame. The source device 201 adds Cnd and Cm to the overhead of the first data frame, and realizes service rate adaptation by inserting invalid data STUFF in the payload area of the data frame.

[0051] Figure 3 This is the first structural schematic diagram of the first service frame provided by the embodiment of the present application. The first service frame 301 includes N multiplex frames. In Figure 3 the example, the N multiplex frames include multiplex frame 1 and multiplex frame 2. Multiplex frame 1 includes overhead 1 and payload 1. PDVal1 is carried in overhead 1. PDVal1 is one of the N first phase discrimination information. PDVal1 is obtained by the source device 201 according to clock information 1 and the local clock. Clock information 1 is the clock information of the CBR1 service data. Payload 1 is used to carry the CBR1 service data. Similarly, multiplex frame 2 includes overhead 2 and payload 2. PDVal2 is carried in overhead 2. PDVal2 is one of the N first phase discrimination information. PDVal2 is obtained by the source device 201 according to clock information 2 and the local clock. Clock information 2 is the clock information of the CBR2 service data. Payload 2 is used to carry the CBR2 service data. Therefore, the phase discrimination information and service data carried in each of the N first multiplex frames correspond.

[0052] According to the previous description, the data frame can be an ODU frame. The service frame can be an OSU frame. Figure 4 This is the schematic diagram of mapping the OSU frame to the OTN frame provided by the embodiment of the present application. As Figure 4 shown, the OTN frame 402 is a schematic diagram of an optical transport network frame. The OTN frame 402 is a structure with 4 rows and multiple columns. The OTN frame 402 includes an overhead area, a payload area, and a forward error correction (FEC) area. It should be understood that the OTN frame 402 is only an example. Other deformed OTN frames are also applicable to the present application. For example, an OTN frame without an FEC area. Another example is a frame structure with different numbers of rows and columns from the OTN frame 402. One or more OSU frames are mapped to the payload area of the OTN frame. The OSU frame 401, as Figure 4As shown, it includes an overhead area and a payload area. Among them, the overhead area of the OSU frame 401 is used to carry overhead information. The overhead information includes one or more overhead fields. The payload area of the OSU frame 401 is used to carry CBR service data. It should be understood that Figure 4 The OSU frame structure shown is only an example. In other specific implementations, the OSU frame may also be a data structure including an overhead sub-frame and a payload sub-frame. This application does not make any limitations in this regard.

[0053] Figure 5 This is a schematic diagram of the processing of the intermediate node transmitting CBR service data provided by the embodiments of this application. In Figure 5 it, the thick solid line represents the clock processing flow, and the thin solid line represents the service processing flow. The intermediate node 501 is used to receive the first data frame from the source device. The intermediate node 501 is used to obtain the clock information of the source device according to the first data frame. For example, the intermediate node 501 recovers the clock information of the source device from the first data frame through (clock and data recovery, CDR) technology. The following will specifically describe this.

[0054] In high-speed data communication such as optical communication, in order to save overhead, the source device usually only transmits data signals and does not transmit the clock signal synchronized with the data signal. At this time, in order to ensure the synchronization of data processing at the data receiving end, the receiving end must be able to extract the clock information from the data. The receiving end re-samples the data according to the clock information to recover the original data signal with a standard waveform, thereby eliminating the jitter accumulated during data transmission. In the CDR technology, the CDR receiver at the receiving end can recover the embedded clock from the data, that is, obtain the clock from the exchange of data signals. The specific clock recovery process can be that the CDR transmitter of the source device first serially transmits the data, and then converts the data into an 8b / 10b coding scheme. The source device obtains 8-bit data through coding processing and converts it into 10-bit symbols. The 8b / 10b coding method can transmit an equal number of 0s and 1s on the data line, thereby reducing inter-symbol interference and providing enough data edges for the CDR receiver to lock the phase on the received data stream. The CDR transmitter multiplies the system clock to the transmission bit rate and transmits the 8b / 10b data on the differential pair on the transmission side at this rate. Then the CDR receiver first locks the phase on the differential bit stream on the receiving side, and the clock of the embedded data can be obtained. In the CDR system, the transmitting and receiving systems usually have completely independent system clocks.

[0055] According to the phase relationship between the local clock and data during data recovery and their different implementation methods, the structure of CDR can generally be divided into three categories: feed forward phase tracking type, feedback phase tracking type, and (without phase tracking) blind oversampling type. Among them, in the feed forward phase tracking type CDR, the phase relationship between the local clock and the input data (during sampling and decision-making) is ensured through continuous feed forward calibration tracking of clock information and precise delay matching design in the circuit and layout design stages. In the feedback phase tracking type CDR, the phase relationship between the local clock and the input data (during sampling and decision-making) is completed by the phase detector monitoring the change in the relative phase between the local clock and data in real time and feeding it back to the control circuit for phase calibration in real time. Blind oversampling CDR refers to an oversampling technique where the sampling clock (frequency and phase) is fixed and not controlled or affected by the input data (feed forward) or the subsequent detection circuit (feedback). In this technique, the specific acquisition of clock and data information is based on a large number of sampling samples obtained through oversampling, and is judged and identified by the subsequent circuit based on algorithms.

[0056] In the embodiments of the present application, the feed forward phase tracking type or the feedback phase tracking type can be used to recover clock data. And both methods can use a PLL-based CDR. The core of this CDR technology is the PLL, which includes a phase detector, a low pass filter (LFP), a voltage controlled oscillator (VCO), and a frequency divider. The VCO is an oscillation circuit whose output frequency has a corresponding relationship with the input control voltage. The frequency divider is used to provide an input frequency for comparison to the PD, then the signal output by the phase detector is low pass filtered, and the voltage controlled oscillator outputs a signal with a corresponding frequency according to the input control voltage, that is, the clock is recovered, and the original data can be recovered by re-sampling the data with the recovered clock.

[0057] The intermediate node 501 is further configured to demap the first data frame to obtain the first service frame. For example, the intermediate node demaps the first data frame through GMP. According to Figure 2As can be seen from the description, the overheads of the N first multiplex frames of the first service frame carry N first phase discrimination information. The N first multiplex frames and the N first phase discrimination information are in one-to-one correspondence. The N first multiplex frames are used to carry N channels of service data. The N channels of service data and the N first multiplex frames are in one-to-one correspondence. The intermediate node 501 is used to obtain N second phase discrimination information according to the N first phase discrimination information and the clock information of the intermediate node. The N first phase discrimination information and the N second phase discrimination information are in one-to-one correspondence. For example, the intermediate node is used to obtain the clock information of the source device 201 through the PLL, and obtain PDVal5 according to the clock information of the source device 201 and the clock information of the intermediate node 501. PDVal5 is used to represent the phase difference between the clock information of the source device 201 and the clock information of the intermediate node 501. The intermediate node 501 obtains N second phase discrimination information according to the N first phase discrimination information and PDVal5. For example, PDVal5 includes PDVal51 and PDVal52. The intermediate node 501 obtains PDVal3 according to PDVal1 and PDVal51. PDVal3 is used to represent the phase relationship between the clock information of the intermediate node 501 and the clock information 1. The intermediate node 501 obtains PDVal4 according to PDVal2 and PDVal52. PDVal4 is used to represent the phase relationship between the clock information of the intermediate node 501 and the clock information 2.

[0058] The intermediate node 501 is further used to obtain a second service frame according to the first service frame. The overheads of the N second multiplex frames of the second service frame carry N second phase discrimination information. The N second multiplex frames and the N second phase discrimination information are in one-to-one correspondence. For example, the intermediate node 501 replaces PDVal1 in the first service frame with PDVal3, and replaces PDVal2 in the first service frame with PDVal4, to obtain the second service frame. The intermediate node 501 maps the second service frame to a second data frame. For example, the intermediate node 501 maps the second service frame to a second data frame through GMP. The intermediate node 501 is used to send the second data frame to the sink device.

[0059] Figure 6 It is a schematic structural diagram of the second service frame provided by the embodiment of the present application. The second service frame 601 includes N multiplex frames. In Figure 6 the example, the N multiplex frames include multiplex frame 11 and multiplex frame 12. Multiplex frame 11 includes overhead 11 and payload 11. PDVal3 is carried in overhead 11. PDVal3 is one of the N second phase discrimination information. Payload 11 is used to carry CBR1 service data. Similarly, multiplex frame 12 includes overhead 12 and payload 12. PDVal2 is carried in overhead 12. PDVal2 is one of the N second phase discrimination information. Payload 12 is used to carry CBR2 service data. Therefore, the phase discrimination information and service data carried by each of the N second multiplex frames correspond.

[0060] It should be understood that in actual applications, the intermediate node 501 may include one or more OTN devices. The above Figure 5 describes the process of transmitting CBR service data when the intermediate node 501 includes one OTN device. For the case where the intermediate node 501 includes multiple OTN devices, for example, Figure 5 the intermediate node 501 in [[ ]] is the first OTN device, and the second OTN device is connected after the first OTN device. At this time, the second OTN device will use the first OTN device as the "transmitting end" and perform similar functions to the first OTN device again, that is, the second OTN device will perform a difference between the phase discrimination information obtained by phase discrimination between the clock information of the first OTN device and the clock information of the second OTN device and the second phase discrimination information in the second service frame, and replace the second phase discrimination information in the previous second service frame with this difference. It can be understood that when the intermediate node 501 includes multiple OTN devices, each OTN device will perform the above operations, so as to "ignore" the clock information of the upper-level OTN device, so that the phase discrimination information carried in the service frame no longer has an association relationship with the clock information of the upper-level OTN device.

[0061] Figure 7 It is a schematic diagram of the processing of the CBR service data transmitted by the sink device provided by the embodiment of the present application. Figure 7 In [[ ]], the thick solid line represents the clock processing process, the thin solid line represents the service processing process, and the dotted line represents the processing process of the Gap clock. The sink device 701 is used to receive the second data frame from the intermediate node 501. After receiving the second data frame, the sink device 701 is used to demap the second data frame to obtain the second service frame. For example, the sink device 701 identifies the valid data in the payload area and the STUFF invalid data according to Cm and Cnd in the overhead of the second data frame, and selects a shielding method for the invalid data during transmission, so as to realize the full recovery of the second service frame. The GapGen PLL of the sink device 701 generates a relatively uniform Gap clock according to the clock information of the intermediate node, Cm and Cnd obtained from the second data frame to match the transmission rate difference between the service frame and the data frame.

[0062] According to Figure 5According to the description, the overheads of the N second multiplex frames of the second service frame carry N second phase discrimination information. The N second multiplex frames and the N second phase discrimination information are in one-to-one correspondence. The sink device 701 is further configured to obtain N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device 701. The N third phase discrimination information and the N second phase discrimination information are in one-to-one correspondence. For example, the sink device 701 is configured to obtain the clock information of the intermediate node 501 through the above CDR technology, and obtain PDVal6 based on the clock information of the intermediate node 501 and the clock information of the sink device 701. PDVal6 is used to represent the phase difference between the clock information of the intermediate node 501 and the clock information of the sink device 701. The sink device 701 obtains N third phase discrimination information based on the N second phase discrimination information and PDVal6. For example, the sink device 701 obtains PDVal7 based on PDVal3 and PDVal6. PDVal7 is used to represent the phase relationship between the clock information of the sink device 701 and the clock information 1. The sink device 701 obtains PDVal8 based on PDVal4 and PDVal6. PDVal8 is used to represent the phase relationship between the clock information of the sink device 701 and the clock information 2. The sink device 701 adjusts the clock information of the sink device 701 according to the N third phase discrimination information, so as to recover the clock information 1 and the clock information 2. The sink device 701 is further configured to demap the second service frame to obtain N CBR service data streams. In Figure 7 In the example of, the N CBR service data streams include CBR1 service data and CBR2 service data. The N clock information includes the clock information 1 and the clock information 2.

[0063] In the embodiments of the present application, the N multiplex frames in the first service frame belong to the same service channel. Therefore, the source device 201 transmits multiple service data streams and corresponding multiple phase discrimination information through one service channel, thereby saving communication resources.

[0064] Figure 8 is a schematic structural diagram of the optical communication system provided by the embodiments of the present application. As Figure 8 shown, the optical communication system includes a source device 201, an intermediate node 501, and a sink device 701.

[0065] The source device 201 is configured to map N CBR service data streams into the N multiplex frames of the first service frame through GMP. The source device 201 is further configured to obtain N clock information of the N CBR service data streams. In Figure 8In the example, the N-channel CBR service data includes CBR1 service data and CBR2 service data. The N clock information includes clock information 1 and clock information 2. Clock information 1 is the clock information of the CBR1 service data. Clock information 2 is the clock information of the CBR2 service data. The source device 201 is used to obtain N first phase discrimination information according to the N clock information and the clock information of the source device 201. In Figure 8 In the example, the source device 201 obtains PDVal1 according to the clock information 1 and the clock information of the source device 201. PDVal1 is used to represent the phase difference between the clock information 1 and the clock information of the source device 201. The source device 201 obtains PDVal2 according to the clock information 2 and the clock information of the source device 201. PDVal2 is used to represent the phase difference between the clock information 2 and the clock information of the source device 201. The source device 201 is used to add the N first phase discrimination information to the overhead inset (OH INS) of the N first multiplex frames. The N first multiplex frames and the N first phase discrimination information are in one-to-one correspondence. The source device 201 is used to map the first service frame to the first data frame through GMP and send the first data frame to the intermediate node 501.

[0066] The intermediate node 501 is used to demap the first data frame through GMP to obtain the first service frame. The intermediate node 501 obtains N second phase discrimination information according to the N first phase discrimination information and the clock information of the intermediate node 501. In Figure 8 In the example, the intermediate node 501 is used to obtain PDVal5 according to the clock information of the source device 201 and the clock information of the intermediate node 501. PDVal5 is used to represent the phase difference between the clock information of the source device 201 and the clock information of the intermediate node 501. The intermediate node 501 is used to obtain PDVal3 according to PDVal1 and PDVal5. PDVal3 is used to represent the phase relationship between the clock information of the intermediate node 501 and the clock information 1. The intermediate node 501 obtains PDVal4 according to PDVal2 and PDVal5. PDVal4 is used to represent the phase relationship between the clock information of the intermediate node 501 and the clock information 2. The intermediate node 501 is also used to obtain the second service frame according to the first service frame. The N second multiplex frames of the second service frame carry the N second phase discrimination information in the overhead. The intermediate node 501 is also used to map the second service frame to the second data frame through GMP and send the second data frame to the sink device 701.

[0067] The sink device 701 is used to receive the second data frame from the intermediate node 501. After receiving the second data frame, the sink device 701 demaps the second data frame through GMP to obtain the second service frame. The sink device 701 is also used to obtain N third phase discrimination information according to the N second phase discrimination information and the clock information of the sink device 701. The N third phase discrimination information corresponds to the N second phase discrimination information one by one. In Figure 8 's example, the sink device 701 is used to obtain PDVal6 according to the clock information of the intermediate node 501 and the clock information of the sink device 701. The sink device 701 obtains PDVal7 according to PDVal3 and PDVal6. The sink device 701 obtains PDVal8 according to PDVal4 and PDVal6. The sink device 701 is also used to adjust the clock information of the sink device 701 according to the N third phase discrimination information, so as to recover the N clock information. The sink device 701 also demaps the second service frame through GMP to obtain N CBR service data. In Figure 8 's example, the N CBR service data includes CBR1 service data and CBR2 service data. The N clock information includes clock information 1 and clock information 2.

[0068] It should be understood that the description about Figure 8 has similarities with the foregoing Figures 2 to 7 's description. Therefore, for the description of the optical communication system in Figure 8 , reference can be made to the description in any of the foregoing Figures 2 to 7 figures. For example, for the description of the source device 201, reference can be made to the description in any of the figures in Figures 2 to 4 .

[0069] According to the foregoing Figure 2 or Figure 8As can be seen from the description, the source device 201 obtains N clock information of N CBR service data. In one implementation, the source device 201 is used to obtain N pulse frequencies of N service data. The N pulse frequencies and the N service data are in one-to-one correspondence. The source device 201 is used to obtain N frequency multiplication coefficients according to the target frequency and the N pulse frequencies. The N frequency multiplication coefficients and the N pulse frequencies are in one-to-one correspondence. The source device 201 is used to multiply the pulse signals of the N service data by the N frequency multiplication coefficients to obtain N clock information. The pulse frequencies of the N clock information are the target frequencies. The N pulse frequencies may be the same or different. For example, the pulse frequency of the CBR1 service data is pulse frequency 1. The pulse frequency of the CBR2 service data is pulse frequency 2. The pulse frequencies of the N clock information are the same. Therefore, when the N pulse frequencies are different, the N frequency multiplication coefficients are also different. For example, the frequency multiplication coefficient corresponding to pulse frequency 1 is FDC1. The frequency multiplication coefficient corresponding to pulse frequency 2 is FDC2. The source device 201 is used to multiply the pulse signal of the CBR1 service data by FDC1. The source device 201 is used to multiply the pulse signal of the CBR2 service data by FDC2. In practical applications, the N first complex frames of the first service frame may also carry the N frequency multiplication coefficients. Figure 9 This is the second structural schematic diagram of the first service frame provided by the embodiment of the present application. As Figure 9 shown, on the basis of Figure 3 , FDC1 and PDVal1 are carried in the overhead 1 of the first service frame 901, and FDC2 and PDVal2 are carried in the overhead 2 of the first service frame 901. Therefore, the frequency multiplication coefficients carried in each of the N first complex frames correspond to the service data.

[0070] When the N first complex frames of the first service frame also carry N multiplication factors, the sink device 701 is further configured to multiply the clock information of the sink device 701 according to the N multiplication factors to obtain N pieces of target clock information. The N multiplication factors and the N pieces of target clock information are in one-to-one correspondence. For example, the sink device 701 is configured to multiply the clock information of the sink device 701 according to FDC1 to obtain target clock information 1. The sink device 701 is configured to multiply the clock information of the sink device 701 according to FDC2 to obtain target clock information 2. The sink device 701 is configured to perform a difference operation on the N pieces of target clock information and the clock information of the sink device 701 to obtain N pieces of fourth phase discrimination information. The N pieces of fourth phase discrimination information and the N pieces of target clock information are in one-to-one correspondence. For example, the sink device 701 is configured to obtain PDval11 according to target clock information 1 and the clock information of the intermediate node 501. The sink device 701 is configured to obtain PDval12 according to target clock information 2 and the clock information of the intermediate node 501. The sink device 701 is configured to perform phase accumulation on the N pieces of fourth phase discrimination information and the N pieces of second phase discrimination information to obtain N pieces of third phase discrimination information. For example, the sink device 701 is configured to obtain PDval7 according to PDval11 and the clock information of PDval3. The sink device 701 is configured to obtain PDval8 according to PDval12 and PDval4.

[0071] As can be known from the foregoing description, the source device 201 is configured to multiply the pulse signals of the N-channel service data according to the N multiplication factors to obtain N pieces of clock information. In practical applications, the source device 201 includes N multipliers. The source device 201 multiplies the N-channel service data according to the N multipliers and the N multiplication factors to obtain N pieces of clock information. The N multipliers and the N multiplication factors are in one-to-one correspondence. When one or more of the N pulse frequencies of the N-channel CBR service data change, the source device 201 is further configured to modify the multiplication factors of the corresponding multipliers so that the frequency of the multiplied pulse signal is still the target frequency.

[0072] In the foregoing Figure 3 example, the N complex frames included in the first service frame 301 carry N pieces of first phase discrimination information. In practical applications, the first service frame 301 may further include more complex frames. It is defined that the complex frames of the first service frame 301 use N complex frames as a complex frame period. Each complex frame period is used to carry N-channel CBR service data. For example, Figure 10 This is the third structural schematic diagram of the first service frame provided by the embodiment of the present application. As Figure 10 shown, the first service frame 1001 uses 2 complex frames as a complex frame period. The first complex frame period includes complex frame 1 and complex frame 2. For the description of the first complex frame period, reference may be made to the foregoing Figure 3Description. The second multi-frame period includes multi-frame 3 and multi-frame 4. Multi-frame 3 includes overhead 3 and payload 3. Payload 3 is used to carry CBR1 service data. Similarly, multi-frame 4 includes overhead 4 and payload 4. Payload 4 is used to carry CBR2 service data. To improve the accuracy of the clock recovery at the sink device, the first service frame 301 carries N first phase discrimination information in each multi-frame period. For example, in Figure 10 , PDVal1 is carried in overhead 3. PDVal2 is carried in overhead 4. It should be understood that payload 3 and payload 1 are used to carry different parts of the CBR1 service data. The clock information of the CBR service data may fluctuate over time. Therefore, the values of PDVal1 carried in overhead 3 and overhead 1 may be different.

[0073] The method for transmitting clock information provided by the present application is described below. Figure 11 It is a schematic flow diagram of the method for transmitting clock information provided by the embodiments of the present application. As Figure 11 shown, the method for transmitting clock information includes the following steps.

[0074] In step 1101, the source device obtains N clock information of N paths of service data.

[0075] The source device 201 is used to receive N paths of CBR service data from the client device or the cloud device. The CBR service data can be E1 service, SDH service, any service or 2M optical service. The source device 201 obtains N clock information of N paths of CBR service data. The N clock information corresponds to the N paths of service data one by one. N is an integer greater than 1.

[0076] In step 1102, the source device obtains N first phase discrimination information according to the N clock information and the clock information of the source device.

[0077] The source device performs phase discrimination on the N clock information and the clock information of the source device to obtain N first phase discrimination information. The N first phase discrimination information corresponds to the N clock information one by one. The clock information of the source device can be generated by the self-oscillation of the device of the source device. The phase discrimination process is that the phase discriminator outputs different voltage signals according to the phase difference between two different input signals, and the voltage signal can reflect the phase difference between the two input signals.

[0078] In step 1103, the source device maps the N paths of service data to N first multi-frames of the first service frame, and maps the first service frame to the first data frame.

[0079] The source device maps N service data streams to N first multiplex frames in the first service frame. The N first multiplex frames correspond one-to-one with the N service data streams. The overheads of the N first multiplex frames carry N first phase discrimination information. The N first multiplex frames correspond one-to-one with the N first phase discrimination information. For example, the source device maps multiple service data streams to N multiplex frames in the first service frame through GMP. The source device maps the first service frame to the first data frame and sends the first data frame to the sending intermediate node. It should be understood that there is no strictly defined timing relationship between step 1103 and steps 1101 and 1102. For example, the source device executes steps 1101 and 1102 during the process of mapping N service data streams to N first multiplex frames in the first service frame.

[0080] In step 1104, the source device sends the first data frame to the intermediate node.

[0081] In step 1105, the intermediate node demaps the first data frame to obtain the first service frame.

[0082] In step 1106, the intermediate node obtains N second phase discrimination information based on the N first phase discrimination information and the clock information of the intermediate node.

[0083] The intermediate node can obtain the clock information of the source device through CDR technology. The intermediate node obtains PDVal5 based on the clock information of the source device and the clock information of the intermediate node. PDVal5 is used to represent the phase difference between the clock information of the source device and the clock information of the intermediate node. The intermediate node obtains N second phase discrimination information based on the N first phase discrimination information and PDVal5.

[0084] In step 1107, the intermediate node obtains the second service frame based on the first service frame. The overheads of the N second multiplex frames in the second service frame carry N second phase discrimination information. The intermediate node maps the second service frame to the second data frame.

[0085] The intermediate node obtains the second service frame based on the first service frame. The overheads of the N second multiplex frames in the second service frame carry N second phase discrimination information. The N second multiplex frames correspond one-to-one with the N second phase discrimination information. For example, the intermediate node replaces PDVal1 in the first service frame with PDVal3 and replaces PDVal2 in the first service frame with PDVal4 to obtain the second service frame. The intermediate node maps the second service frame to the second data frame. For example, the intermediate node maps the second service frame to the second data frame through GMP.

[0086] In step 1108, the intermediate node sends the second data frame to the sink device.

[0087] In step 1109, the sink device demaps the second data frame to obtain the second service frame.

[0088] In step 1110, the sink device obtains N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device, and adjusts the clock information of the sink device according to the N third phase discrimination information.

[0089] The sink device obtains N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device. The N third phase discrimination information corresponds one-to-one with the N second phase discrimination information. For example, the sink device is used to obtain the clock information of the intermediate node through CDR technology, and obtains PDVal6 based on the clock information of the intermediate node and the clock information of the sink device. PDVal6 is used to represent the phase difference between the clock information of the intermediate node and the clock information of the sink device. The sink device obtains N third phase discrimination information from the N second phase discrimination information and PDVal6. The sink device adjusts the clock information of the sink device according to the N third phase discrimination information, thereby restoring clock information 1 and clock information 2. The sink device is also used to demap the second service frame to obtain N CBR service data streams.

[0090] Figure 12 This is the first structural schematic diagram of the OTN device provided by the embodiment of the present application. The OTN device 1200 can be Figure 1 any device among the source device 101, the sink device 102 or the intermediate subnet 103 in Figure 2 . The OTN device 200 can be Figure 5 the source device 201 in Figure 7 , the intermediate node 501 in Figure 12 . As shown in

[0091] The tributary board 1201, the cross-connect board 1202, and the line board 1203 are used to process electrical layer signals. Among them, the tributary board 1201 is used to implement the reception and transmission of various client signals, such as SDH services, packet services, Ethernet services, and / or fronthaul services, etc. Further, the tributary board 201 can be divided into a client-side optical transceiver module and a signal processor. Among them, the client-side optical transceiver module can also be referred to as an optical transceiver, and is used to receive and / or transmit service data. The signal processor is used to implement the mapping and demapping processing of service data to data frames. The cross-connect board 1202 is used to implement the exchange of data frames and complete the exchange of one or more types of data frames. The line board 1203 mainly implements the processing of line-side data frames. Specifically, the line board 1203 can be divided into a line-side optical module and a signal processor. Among them, the line-side optical module can be referred to as an optical transceiver and is used to receive and / or transmit data frames. The signal processor is used to implement the mapping and demapping of line-side data frames, or mapping and demapping processing. The system control and communication class single board 1204 is used to implement system control; specifically, it can collect information from different single boards or send control instructions to the corresponding single boards. Unless otherwise specified, the specific components (such as signal processors) can be one or more, and this application does not make any restrictions. It should also be noted that this application does not make any restrictions on the types of single boards included in the device, the functional design, and the number of single boards. It should be noted that in specific implementations, the above two single boards may also be designed as one single board. In addition, the network device may also include a backup power supply, a fan for heat dissipation, etc.

[0092] It should be understood that Figure 12 This is only an example of the OTN device provided by this application. According to specific needs, the types and quantities of single boards included in the OTN device may be different. For example, the OTN device as a core node does not have a tributary board 1201. Another example is that the OTN device as an edge node has multiple tributary boards 1201 or does not have an optical cross-connect board 1202.

[0093] Figure 13 This is the second structural schematic diagram of the OTN device provided by the embodiment of this application. The OTN device 1300 includes a processing module 1301 and a transceiver module 1302. The OTN device 1300 can be a source device, an intermediate node, or a sink device.

[0094] When the OTN device 1300 is a source device, the processing module 1301 is used to obtain N clock information of N service data. The N clock information corresponds to the N service data one by one. N is an integer greater than 1. The processing module 1301 is further used to obtain N first phase discrimination information according to the N clock information and the clock information of the source device. The N first phase discrimination information corresponds to the N clock information one by one. The processing module 1301 is further used to map the N service data into N first multiplex frames of the first service frame. The N first multiplex frames correspond to the N service data one by one. The N first multiplex frames carry the N first phase discrimination information in the overhead. The N first multiplex frames correspond to the N first phase discrimination information one by one. The processing module 1301 is further used to map the first service frame into a first data frame. The transceiver module 1302 is further used to send the first data frame.

[0095] When the OTN device 1300 is an intermediate node, the transceiver module 1302 is used to receive the first data frame. The processing module 1301 is used to demap the first data frame to obtain the first service frame. The N first multiplex frames of the first service frame carry the N first phase discrimination information in the overhead. The N first multiplex frames correspond to the N first phase discrimination information one by one. N is an integer greater than 1. The N first multiplex frames are used to carry N service data. The N service data corresponds to the N first multiplex frames one by one. The processing module 1301 is further used to obtain N second phase discrimination information according to the N first phase discrimination information and the clock information of the intermediate node. The N first phase discrimination information corresponds to the N second phase discrimination information one by one. The processing module 1301 is further used to obtain a second service frame according to the first service frame. The N second multiplex frames of the second service frame carry the N second phase discrimination information in the overhead. The N second multiplex frames correspond to the N second phase discrimination information one by one. The processing module 1301 is further used to map the second service frame into a second data frame. The transceiver module 1302 is further used to send the second data frame.

[0096] When the OTN device 1300 is a sink device, the transceiver module 1302 is used to receive the second data frame. The processing module 1301 is used to demap the second data frame to obtain the second service frame. The N second multiplex frames of the second service frame carry the N second phase discrimination information in the overhead. The N second multiplex frames correspond to the N second phase discrimination information one by one. N is an integer greater than 1. The N second multiplex frames are used to carry N service data. The N service data corresponds to the N second multiplex frames one by one. The processing module 1301 is further used to obtain N third phase discrimination information according to the N second phase discrimination information and the clock information of the sink device. The N third phase discrimination information corresponds to the N second phase discrimination information one by one. The processing module 1301 is further used to adjust the clock information of the sink device according to the N third phase discrimination information.

[0097] It should be understood that there are similarities between the description of the OTN device 1300 and the description of the aforementioned optical communication system. Therefore, for the description of the OTN device 1300, reference can be made to the description of the optical communication system above. For example, the phase discrimination information carried in each of the N first multiplex frames corresponds to the service data. Another example is that when the OTN device 1300 is a source device, the processing module 1301 is used to multiply the frequency of N paths of service data according to N frequency multipliers and N frequency multiplication coefficients to obtain N clock information, and the N frequency multipliers and the N frequency multiplication coefficients correspond one by one. When the frequencies of the N pulses change, the processing module 1301 is also used to modify the frequency multiplication coefficients of the N frequency multipliers.

[0098] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should be covered within the protection scope of the present application.

Claims

1. A method for transmitting clock information, characterized in that, including: The source device obtains N clock information of N pieces of service data, where the N clock information corresponds one-to-one with the N pieces of service data, and N is an integer greater than 1; The source device obtains N first phase discrimination information according to the N clock information and the clock information of the source device, and the N first phase discrimination information corresponds one-to-one with the N clock information; The source device maps the N pieces of service data into N first multiplex frames of a first service frame, the N first multiplex frames correspond one-to-one with the N pieces of service data, and the N first multiplex frames carry the N first phase discrimination information in the overhead, and the N first multiplex frames correspond one-to-one with the N first phase discrimination information; The source device maps the first service frame into a first data frame and sends the first data frame.

2. The method for transmitting clock information according to claim 1, wherein The phase discrimination information carried in each multiplex frame among the N first multiplex frames corresponds to the service data.

3. The method for transmitting clock information according to claim 1 or 2, characterized in that In the first service frame, the first multiplex frame among the N first multiplex frames and the next multiplex frame of the N first multiplex frames carry the phase discrimination information of the same piece of service data.

4. The method for transmitting clock information according to any one of claims 1 to 3, characterized in that, The source device obtaining the N clock information of the N pieces of service data includes: The source device obtains N pulse frequencies of the N pieces of service data, and the N pulse frequencies correspond one-to-one with the N pieces of service data; The source device obtains N frequency multiplication coefficients according to a target frequency and the N pulse frequencies, and the N frequency multiplication coefficients correspond one-to-one with the N pulse frequencies; The source device multiplies the pulse signals of the N pieces of service data according to the N frequency multiplication coefficients to obtain the N clock information, and the pulse frequencies of the N clock information are the target frequency.

5. The method for transmitting clock information according to claim 4, characterized in that, The first service frame carries the N frequency multiplication coefficients.

6. The method for transmitting clock information according to claim 4 or 5, characterized in that The N first multiplex frames carry the N frequency multiplication coefficients, and the frequency multiplication coefficient carried in each of the N first multiplex frames corresponds to the service data.

7. The method for transmitting clock information according to any one of claims 4 to 6, characterized in that The source device multiplying the N pieces of service data according to the N frequency multiplication coefficients to obtain the N clock information includes: the source device multiplies the N pieces of service data according to N frequency multipliers and the N frequency multiplication coefficients to obtain the N clock information, and the N frequency multipliers correspond one-to-one with the N frequency multiplication coefficients; The method further includes: when the N pulse frequencies change, the source device modifies the frequency multiplication coefficients of the N frequency multipliers.

8. A method for transmitting clock information, characterized in that, including: The intermediate node receives a first data frame; The intermediate node demaps the first data frame to obtain a first service frame. The overhead of the N first multiplex frames of the first service frame carries N first phase discrimination information, and the N first multiplex frames correspond one-to-one with the N first phase discrimination information. N is an integer greater than 1. The N first multiplex frames are used to carry N pieces of service data, and the N pieces of service data correspond one-to-one with the N first multiplex frames; The intermediate node obtains N second phase discrimination information according to the N first phase discrimination information and the clock information of the intermediate node, and the N first phase discrimination information corresponds one-to-one with the N second phase discrimination information; The intermediate node obtains a second service frame based on the first service frame, and N second phase discrimination information is carried in the overheads of N second multiplex frames of the second service frame, and the N second multiplex frames and the N second phase discrimination information are in one-to-one correspondence; The source device maps the second service frame to a second data frame and sends the second data frame.

9. The method for transmitting clock information according to claim 8, wherein The phase discrimination information carried in each of the N second multiplex frames corresponds to the service data.

10. The method for transmitting clock information according to claim 8 or 9, characterized in that, In the second service frame, the first multiplex frame of the N second multiplex frames and the next multiplex frame of the N second multiplex frames carry the phase discrimination information of the same path of service data.

11. A method for transmitting clock information, characterized in that, Including: The sink device receives the second data frame; The sink device demaps the second data frame to obtain a second service frame, and N second phase discrimination information is carried in the overheads of N second multiplex frames of the second service frame, and the N second multiplex frames and the N second phase discrimination information are in one-to-one correspondence. N is an integer greater than 1. The N second multiplex frames are used to carry N paths of service data, and the N paths of service data and the N second multiplex frames are in one-to-one correspondence; The sink device obtains N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device, and the N third phase discrimination information and the N second phase discrimination information are in one-to-one correspondence; The sink device adjusts the clock information of the sink device according to the N third phase discrimination information.

12. The method for transmitting clock information according to claim 11, wherein N frequency multiplication coefficients are carried in the overheads of N second multiplex frames of the second service frame; The sink device obtaining N third phase discrimination information based on the N second phase discrimination information and the clock information of the sink device includes: The sink device multiplies the clock information of the sink device by the N frequency multiplication coefficients to obtain N target clock information, and the N frequency multiplication coefficients and the N target clock information are in one-to-one correspondence; The sink device performs a difference operation on the N target clock information and the clock information of the sink device to obtain the N fourth phase discrimination information, and the N fourth phase discrimination information and the N target clock information are in one-to-one correspondence; The sink device performs phase accumulation on the N fourth phase discrimination information and the N second phase discrimination information to obtain the N third phase discrimination information.

13. A communication device, characterized in that, Including a processing module and a transceiver module, wherein: The processing module is configured to obtain N clock information of the N paths of service data, and the N clock information and the N paths of service data are in one-to-one correspondence. N is an integer greater than 1. Based on the N clock information and the clock information of the source device, N first phase discrimination information is obtained, and the N first phase discrimination information and the N clock information are in one-to-one correspondence; The processing module is further configured to map the N paths of service data into N first multiplex frames of a first service frame, and the N first multiplex frames and the N paths of service data are in one-to-one correspondence. The overheads of the N first multiplex frames carry the N first phase discrimination information, and the N first multiplex frames and the N first phase discrimination information are in one-to-one correspondence, and map the first service frame to a first data frame; The transceiver module is configured to send the first data frame.

14. The communication device according to claim 13, wherein The processing module is used to obtain N clock information of the N-channel service data, including: the processing module is used to obtain N pulse frequencies of the N-channel service data, the N pulse frequencies correspond to the N-channel service data one by one, N frequency multiplication coefficients are obtained according to the target frequency and the N pulse frequencies, the N frequency multiplication coefficients correspond to the N pulse frequencies one by one, the pulse signals of the N-channel service data are frequency-multiplied according to the N frequency multiplication coefficients to obtain the N clock information, and the pulse frequencies of the N clock information are the target frequency.

15. The communication device according to claim 14, wherein The processing module is used to frequency-multiply the N-channel service data according to the N frequency multiplication coefficients to obtain the N clock information, including: the processing module is used to frequency-multiply the N-channel service data according to N frequency multipliers and the N frequency multiplication coefficients to obtain the N clock information, and the N frequency multipliers correspond to the N frequency multiplication coefficients one by one; When the N pulse frequencies change, the processing module is further used to modify the frequency multiplication coefficients of the N frequency multipliers.

16. A communication device, characterized in that, It includes a processing module and a transceiver module, where: The transceiver module is used to receive the first data frame; The processing module is used to demap the first data frame to obtain a first service frame. The overheads of N first multiplex frames of the first service frame carry N first phase discrimination information, the N first multiplex frames correspond to the N first phase discrimination information one by one, N is an integer greater than 1, the N first multiplex frames are used to carry N-channel service data, and the N-channel service data corresponds to the N first multiplex frames one by one; The processing module is further used to obtain N second phase discrimination information according to the N first phase discrimination information and the clock information of the intermediate node, the N first phase discrimination information corresponds to the N second phase discrimination information one by one, a second service frame is obtained according to the first service frame, the overheads of N second multiplex frames of the second service frame carry the N second phase discrimination information, the N second multiplex frames correspond to the N second phase discrimination information one by one, and the second service frame is mapped to a second data frame; The transceiver module is further used to send the second data frame.

17. The communication device according to claim 16, wherein, The phase discrimination information carried by each multiplex frame in the N second multiplex frames corresponds to the service data.

18. The communication device according to claim 16 or 17, characterized in that, In the second service frame, the first multiplex frame of the N second multiplex frames and the next multiplex frame of the N second multiplex frames carry the phase discrimination information of the same-channel service data.

19. A communication device, characterized in that, It includes a processing module and a transceiver module, where: The transceiver module is used to receive the second data frame; The processing module is used to demap the second data frame to obtain a second service frame. The overheads of N second multiplex frames of the second service frame carry N second phase discrimination information, the N second multiplex frames correspond to the N second phase discrimination information one by one, N is an integer greater than 1, the N second multiplex frames are used to carry N-channel service data, and the N-channel service data corresponds to the N second multiplex frames one by one; The processing module is further configured to obtain N third phase discrimination information according to the N second phase discrimination information and the clock information of the sink device, where the N third phase discrimination information corresponds to the N second phase discrimination information one by one, and adjust the clock information of the sink device according to the N third phase discrimination information.

20. The communication device according to claim 19, wherein, The overheads of the N second multiplex frames of the second service frame carry N frequency multiplication factors; The processing module is configured to obtain N third phase discrimination information according to the N second phase discrimination information and the clock information of the sink device, including: The processing module is configured to multiply the clock information of the sink device by the N frequency multiplication factors to obtain N target clock information, where the N frequency multiplication factors correspond to the N target clock information one by one, and perform a difference operation on the N target clock information and the N second phase discrimination information to obtain the N third phase discrimination information.

21. An optical communication system, characterized in that, The optical communication system includes the communication device according to any one of claims 13 to 15, the communication device according to any one of claims 16 to 18, and the communication device according to any one of claims 19 to 20.

22. An optical communication system, characterized in that, The optical communication system includes a source device, an intermediate node, and a sink device. The source device is configured to execute the method according to any one of the foregoing claims 1 to 7, the intermediate node is configured to execute the method according to any one of the foregoing claims 8 to 10, and the sink device is configured to execute the method according to any one of the foregoing claims 11 to 12.

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