Method, device and system for multiplexing OSU to OPU

Abstract

The invention discloses a method, device and system for multiplexing an OSU to an OPU, and relates to the field of optical communication. The method comprises the following steps: in an OSU service mapping process, a source end takes every three OPU frames as an OPU multiframe, two specified payload blocks are reserved in a payload area of each OPU multiframe, and the OSU service in a transmission period is mapped to the rest P-2N payload blocks; the source end inserts non-data frames in two payload blocks reserved by each OPU multiframe, the non-data frames carry multiframe counting numbers of the OPU multiframes and corresponding multiplexing structure identifiers, and the non-data frames are used for updating a local multiframe counting number and multiplexing structure identifier configuration table by the sink end according to the information; and looking up the multiplexing structure identifier configuration table by taking the payload block counting number in the multiframe and the multiframe counting number as addresses to obtain an OSU service channel number corresponding to the payload block. According to the invention, inter-channel crosstalk can be avoided, the OSU service channel number can be quickly obtained, and application requirements are met.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technologies, and more specifically, to a method, apparatus, and system for multiplexing an OSU (Optical Service Unit) into an OPU (Optical Payload Unit). Background Art

[0002] OSU is a technical improvement made for the technical shortcomings of traditional OTN (Optical Transport Network). It changes the characteristic of the traditional OTN that uses time slot division for frame structure and adopts a more flexible payload block division method. It can efficiently carry Ethernet services such as FE / GE / 10GE / 25GE / 50GE / 100GE (bandwidth range from 2 Mb / s to 10 Gb / s), CBR services such as STM-1 / STM-4 / VC-n (including E1), and supports a connection number of the k level. The simplified bandwidth lossless adjustment mechanism can well meet the needs of customers for flexible variable service bandwidths.

[0003] Defined in the CCSA (China Communications Standards Association) standard, the reference rate of OSU is 2.6 Mb / s. Different types of customer services are mapped to OSU, and the OSU rate they carry is a multiple of the reference rate. The length of the OSU frame is 192 bytes.

[0004] At the same time, the standard defines that the transmission period is the time for the OPU to continuously transmit P payload blocks (192 bytes), and one payload block loads one OSU frame. The rate of each payload block within the transmission period is slightly larger than 2.6 Mb / s and can carry the reference rate of OSU. If an OSU service with a rate of C * 2.6 Mb / s will occupy C payload blocks within one transmission period.

[0005] As Figure 1 shown, the P values defined in the standard for different ODU types within one transmission period are listed. Figure 1 Among the P values in Figure 2 except that the P values of ODU0 and ODU1 have an integer multiple relationship with the OPU payload length, the P values of other types of ODU are not integer multiples of the OPU payload length. This will cause the positions of the P payload blocks within each transmission period in the OPU to change (constantly slide). As

[0006] Therefore, in the standard, the service channel number corresponding to the OSU frame is identified by defining the OSU frame overhead TPN (Tributary Port Number), and then CRC-8 is used to verify the correctness of the overhead of the first 6 bytes including TPN, as Figure 3 shown, Figure 3 is the OSU frame structure defined in the standard. However, this solution has the following technical problems: 1) The OSU frame uses CRC-8 to verify 6 bytes of data, and there is a certain probability that errors cannot be detected, and it cannot ensure that the TPN is correct. At this time, the TPN may correspond to other OSU service channels, resulting in crosstalk between channels.

[0007] 2) When the OSU frame CRC-8 detects an error, the TPN at this time is not trustworthy and cannot correspond to the corresponding OSU service channel, resulting in the inability to know which channel has an error; at the same time, the OSU frame with CRC-8 error will be discarded, which will also increase the alarm detection time of protection switching. Summary of the Invention

[0008] The purpose of the present invention is to provide a method, device and system for multiplexing OSU to OPU, which can not only avoid crosstalk between channels, effectively improve the anti-interference ability between channels, but also quickly obtain the OSU service channel number corresponding to each payload block by looking up a table, provide support for quickly locating the error channel number, reduce the channel alarm detection time, and meet the actual application requirements.

[0009] To achieve the above purpose, in the first aspect, an embodiment of the present invention provides a method for multiplexing OSU to OPU, and the method includes: The source end maps the OSU service to the payload block of the OPU; during the mapping process, every three OPU frames are used as an OPU multi-frame, and two specified payload blocks are reserved in the payload area of each OPU multi-frame, and the OSU service within the transmission period is mapped to the remaining P - 2N payload blocks, and the corresponding multiplexing structure identifier is obtained; where P is the P value of various redefined ODU types, and P satisfies that P is an integer multiple of 238 N; The source end inserts two non-data frames into the two specified payload blocks reserved in each OPU multi-frame, and the two non-data frames carry the multi-frame count number of the OPU multi-frame and the multiplexing structure identifier corresponding to the OPU multi-frame; where the multi-frame count number and the multiplexing structure identifier are used for the sink end to update the local multi-frame count number and multiplexing structure identifier configuration table according to this information, and by using the payload block count number and the multi-frame count number within the multi-frame as addresses to look up the multiplexing structure identifier configuration table, the OSU service channel number corresponding to the payload block is obtained.

[0010] In combination with the first aspect, in one embodiment, the source end maps the OSU service into the payload blocks of the OPU, including: The source end configures the number P of payload blocks within the transmission period according to the ODU type according to the redefined P value; takes every three OPU frames as an OPU multiplex frame, reserves two specified payload blocks in the payload area of each OPU multiplex frame, calculates the distribution positions of each OSU service within the remaining P - 2N payload blocks within the transmission period according to a preset algorithm and rules, and writes them into the multiplexing structure identification configuration table; After the source end determines the order of the three OPU frames and the boundaries of the payload blocks by inserting 0, 64, and 128 into the OPU multiplex frame overhead PBP respectively, it performs payload block counting and numbering on the P - 2N payload blocks where the OSU service is located within the period with P - 2N as the period, and looks up the multiplexing structure identification configuration table using the payload block counting number to obtain the OSU service channel number corresponding to the payload block; If OSU service data has arrived in the OSU service channel corresponding to the payload block, load the data into the payload block; if no OSU service data has arrived in the OSU service channel corresponding to the payload block, load the IDLE frame into the payload block for filling.

[0011] In combination with the first aspect, in one embodiment, the source end inserts two non-data frames into the two specified payload blocks reserved in each OPU multiplex frame, including: The source end counts and numbers all OPU multiplex frames within one transmission period, and places the multiplex frame count number of each OPU multiplex frame into the two non-data frames; the source end takes the multiplex frame count number as the address, obtains the channel numbers of the OSU carried by the 236 payload blocks of each OPU multiplex frame from the multiplexing structure configuration table, and places them into the two non-data frames of each OPU multiplex frame; inserts the two processed non-data frames into the two specified payload blocks reserved in the corresponding OPU multiplex frame.

[0012] In combination with the first aspect, in one embodiment, the method further includes: The source end inserts the multiplex frame count number verification information and the multiplexing structure identification verification information into the two non-data frames; the multiplex frame count number verification information is the result of performing CRC calculation on the multiplex frame count number, which is used for the sink end to verify the validity of the multiplex frame count number according to this information; the multiplexing structure identification verification information is the result of performing CRC calculation on the multiplexing structure identification, which is used for the sink end to verify the validity of the multiplexing structure identification according to this information.

[0013] In combination with the first aspect, in one embodiment, the method further includes: the source end inserts a non-data frame payload block identifier into the two non-data frames, which is used to indicate that the payload block is a payload block inserted with a non-data frame.

[0014] In a second aspect, an embodiment of the present invention further provides a method for multiplexing OSU into OPU. The method includes: After the sink end completes the framing of the OPU multiframe through the PBP in the OPU overhead, it counts and numbers the payload blocks mapped with OSU services within the OPU multiframe, and extracts two non-data frames from two specified payload blocks in the OPU multiframe. The multiframe count number of the OPU multiframe and the multiplexing structure identifier corresponding to the OPU multiframe carried in the two non-data frames are used to update the local multiframe count number and multiplexing structure identifier configuration table; The sink end looks up the multiplexing structure identifier configuration table by using the payload block count number and multiframe count number within the multiframe as addresses to obtain the OSU service channel number corresponding to the payload block.

[0015] In combination with the second aspect, in an implementation, if the two non-data frames extracted also have the multiframe count number verification information and multiplexing structure identifier verification information inserted, the sink end will verify the validity of the extracted multiframe count number and multiplexing structure identifier according to this information; and only when the verification is valid, will it update the local multiframe count number and multiplexing structure identifier configuration table.

[0016] In a third aspect, an embodiment of the present invention further provides a source end device for implementing the method in the first aspect. The source end device includes an OSU mapping module and a non-data frame insertion module; The OSU mapping module is configured to: map the OSU service to the payload block of the OPU; during the mapping process, take every three OPU frames as an OPU multiframe, reserve two specified payload blocks in the payload area of each OPU multiframe, map the OSU services within the transmission period to the remaining P - 2N payload blocks, and obtain the corresponding multiplexing structure identifier; where P is the P value of various redefined ODU types, and P satisfies that P is an integer multiple of 238N; The non-data frame insertion module is configured to: insert two non-data frames into two specified payload blocks reserved in each OPU multiframe. The two non-data frames carry the multiframe count number of the OPU multiframe and the multiplexing structure identifier corresponding to the OPU multiframe; where the multiframe count number and the multiplexing structure identifier are used for the sink end to update the local multiframe count number and multiplexing structure identifier configuration table according to this information, and by using the payload block count number and multiframe count number within the multiframe as addresses to look up the multiplexing structure identifier configuration table, obtain the OSU service channel number corresponding to the payload block.

[0017] In a fourth aspect, an embodiment of the present invention further provides a sink end device for implementing the method in the second aspect. The sink end device includes a multiframe framing module, a non-data frame extraction module, and a multiplexing structure identifier lookup module; The multiple-frame framing module is configured to: complete the framing of the OPU multiple-frame through the PBP in the OPU overhead; The non-data frame extraction module is configured to: after the multiple-frame framing module completes the framing of the OPU multiple-frame, perform payload block counting and numbering on the payload blocks mapped with OSU services within the OPU multiple-frame, and extract two non-data frames from two specified payload blocks of the OPU multiple-frame, and update the local multiple-frame count number and multiplexing structure identification configuration table through the multiple-frame count number of the OPU multiple-frame carried in the two non-data frames and the multiplexing structure identification corresponding to the OPU multiple-frame; The multiplexing structure identification look-up table module is configured to: look up the multiplexing structure identification configuration table by using the payload block count number and the multiple-frame count number within the multiple-frame as addresses to obtain the OSU service channel number corresponding to the payload block.

[0018] In a fifth aspect, an embodiment of the present invention further provides a system for multiplexing OSU into OPU, where the system includes a source-end device according to the embodiment of the third aspect and a sink-end device according to the embodiment of the fourth aspect.

[0019] The beneficial effects brought by the technical solutions provided by the embodiments of the present application include: In this embodiment, every three OPU frames are used as an OPU multiple-frame, and the P value under various ODU types is redefined to make it satisfy that P is an integer multiple N of 238. In this way, for various ODU types, there are N OPU multiple-frames in one transmission period, each multiple-frame has three OPU frames, and the positions of the P payload blocks in the OPU within each transmission period will not change (will not keep sliding). Moreover, in this embodiment, two non-data frames are inserted into two specified payload blocks reserved in each OPU multiple-frame. The two non-data frames carry the multiple-frame count number of the OPU multiple-frame and the multiplexing structure identification corresponding to the OPU multiple-frame; through the non-data frame, the multiple-frame count number information of the source end can be sent to the sink end, and after synchronous update at the sink end, the multiple-frame count number and payload block count number of the sink end can be made consistent with those of the source end; at the same time, the multiplexing structure identification of the source end is also sent to the sink end through the non-data frame, so that the sink end can quickly obtain the channel number of the OSU through simple look-up table.

[0020] Therefore, by adopting the solution of the embodiment of the present application, it is possible to effectively ensure the consistency of the multiplexing structure of P payload blocks within the transmission period obtained at the source end and the sink end, prevent the situation of incorrect correspondence of the OSU service channel, thereby avoiding crosstalk between channels, and effectively improving the anti-interference ability between channels; moreover, by adopting the solution of the embodiment of the present application, even when an error is detected by the OSU frame CRC-8, it is not necessary to rely on the TPN, and no packets will be actively discarded. By looking up the table through the payload block count number and the multi-frame count number within the multi-frame, the error channel number can be quickly located, thereby reducing the time for channel alarm detection. Description of the Drawings

[0021] Figure 1 is the P value under different ODU types within a transmission period defined in the CCSA standard; Figure 2 is the schematic diagram of the transmission period in the OPU; Figure 3 is the OSU frame structure defined in the CCSA standard; Figure 4 is the schematic flow chart of an embodiment of the method for multiplexing OSU to OPU in the first aspect of the present application; Figure 5 is the schematic diagram of inserting an OAM frame into the first and second payload blocks of each OPU multi-frame in an example; Figure 6 is the redefined P value under various ODU types in the embodiment of the present application; Figure 7 is the specific schematic flow chart of step A1 in the embodiment of the present application; Figure 8 is the specific schematic flow chart of step A2 in the embodiment of the present application; Figure 9 is the schematic diagram of the structure of two non-data frames being OAM frames in an example Figure 10 is the schematic flow chart of an embodiment of the method for multiplexing OSU to OPU in the second aspect of the present application; Figure 10 is the schematic flow chart of another embodiment of the method for multiplexing OSU to OPU in the second aspect of the present application; Figure 11 is the schematic diagram of the functional modules of an embodiment of the source end device of the present application; Figure 12 is the schematic diagram of the functional modules of an embodiment of the sink end device of the present application; Figure 13 is the schematic architecture diagram of an embodiment of the system for multiplexing OSU to OPU of the present application. Detailed Embodiments

[0022] To make the technical problems, technical solutions, and advantages to be solved by the present invention clearer, the technical solutions of the present invention will be described in detail below in conjunction with the specification drawings and specific embodiments.

[0023] It should be noted that: the examples to be introduced next are only some specific examples, and do not limit the embodiments of the present invention to the following specific steps, numerical values, conditions, data, order, etc. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0024] In a first aspect, an embodiment of this application provides a method for multiplexing OSU to OPU.

[0025] In one embodiment, referring to Figure 4 as shown, Figure 4 is a schematic flowchart of an embodiment of the method for multiplexing OSU to OPU in the first aspect of this application. As Figure 4 shown, a method for multiplexing OSU to OPU includes: Step A1: The source end maps the OSU service to the payload block of the OPU; during the mapping process, every three OPU frames are used as an OPU multiplex frame, and two specified payload blocks are reserved in the payload area of each OPU multiplex frame. The OSU service within the transmission period is mapped to the remaining P - 2N payload blocks, and the corresponding multiplexing structure identifier is obtained; where P is the P value of various re - defined ODU types, and it satisfies that P is an integer multiple N of 238; the obtained multiplexing structure identifier is the OSU service channel number corresponding to the payload block count number of the P - 2N payload blocks.

[0026] It can be understood that in order to implement the multiplexing of OSU to OPU in this embodiment, first, the source end needs to map the OSU service to the payload block of the OPU. Different from the prior art, in this embodiment, every three OPU frames are used as an OPU multiplex frame, as Figure 5 shown. Since the payload block of an OSU (i.e., PB block) is 192 bytes, there are exactly 238 payload blocks in the payloads of three OPU frames; at the same time, on the basis of meeting the requirement that the rate of the OPU payload block in the standard is greater than the reference rate of OSU by 1000 ppm, this embodiment will re - define the P value under various ODU types to make it satisfy that P is an integer multiple N of 238, as Figure 6As shown in the figure. In this way, for various ODU types, a transmission period contains N OPU multiplex frames. Each multiplex frame has three OPU frames, and the positions of the P payload blocks in the OPU within each transmission period do not change (do not slide continuously). Therefore, by numbering the multiplex frames within the transmission period, with the numbering range from 0 to (N - 1), the boundaries of the P payload blocks in the OPU frames within the transmission period can be determined. In addition, different from the prior art, in the mapping process of this embodiment, two specified payload blocks are also reserved in the payload area of each OPU multiplex frame, and the OSU services within the transmission period are mapped to the remaining P - 2N payload blocks. The two specified reserved payload blocks are prepared for the subsequent insertion of non-data frames (used to transmit the multiplex frame count number and the multiplexing structure identifier corresponding to the multiplex frame). For the specific content regarding the insertion of non-data frames, please refer to the description of step A2 later, and it will not be elaborated here.

[0027] Exemplarily, refer to Figure 7 As shown in the figure, as an alternative implementation manner, step A1 specifically includes: A101. The source end configures the number P of payload blocks within the transmission period according to the ODU type according to the redefined P value; takes every three OPU frames as an OPU multiplex frame, reserves two specified payload blocks in the payload area of each OPU multiplex frame, calculates the distribution positions of each OSU service within the transmission period in the remaining P - 2N payload blocks according to a preset algorithm and rules, and writes them into the multiplexing structure identifier configuration table. For example, after the source end chip is powered on, the software can configure the number P of payload blocks within the transmission period according to the ODU type according to the redefined P value, and can also use a preset algorithm such as the uniformization algorithm through software or hardware to calculate the distribution positions of each OSU service within the transmission period in the remaining P - 2N payload blocks. And in practical applications, the two specified reserved payload blocks in the payload area can also be indicated by setting an indication identifier, which can facilitate quickly locating the two reserved payload blocks and is convenient for the subsequent insertion of non-data frames, such as setting the PB - OAM1 payload block indication and the PB - OAM2 payload block indication.

[0028] A102. After the source end determines the order of the three OPU frames and the boundaries of the payload blocks by inserting 0, 64, and 128 into the OPU multiplex frame overhead PBP respectively, it numbers the P - 2N payload blocks where the OSU services are located within the period with a period of P - 2N, and looks up the multiplexing structure identifier configuration table using the payload block count number to obtain the OSU service channel number corresponding to the payload block; if there is OSU service data that has arrived in the OSU service channel corresponding to the payload block, load the data into the payload block; if there is no OSU service data arriving in the OSU service channel corresponding to the payload block, load the IDLE frame into the payload block for filling.

[0029] Step A2: The source end inserts two non-data frames into two specified payload blocks reserved in each OPU multiframe. The two non-data frames carry the multiframe count number of the OPU multiframe and the multiplexing structure identifier corresponding to the OPU multiframe. Wherein, the multiframe count number and the multiplexing structure identifier are used by the sink end to update the local multiframe count number and multiplexing structure identifier configuration table, and by using the payload block count number and multiframe count number within the multiframe as addresses to look up the multiplexing structure identifier configuration table, the OSU service channel number corresponding to the payload block is obtained.

[0030] It can be understood that, different from the prior art, in this embodiment, after the mapping of the OSU service to the payload blocks of the OPU is completed, two non-data frames are inserted into two specified payload blocks reserved in each OPU multiframe. The two non-data frames carry the multiframe count number of the OPU multiframe and the multiplexing structure identifier corresponding to the OPU multiframe. Through these non-data frames, the multiframe count number information of the source end can be sent to the sink end, and after synchronization and update at the sink end, the multiframe count number and payload block count number of the sink end can be made consistent with those of the source end; at the same time, the multiplexing structure identifier of the source end is also sent to the sink end through these non-data frames, so that the sink end can quickly obtain the channel number of the OSU through simple table lookup, simplify the configuration of the sink end, and can adapt to different algorithms and rules.

[0031] In practical applications, the two payload blocks for inserting the two non-data frames can be any two specified payload blocks in the OPU multiframe. For example, it can be specified that the first payload block and the second payload block in each OPU multiframe are fixedly inserted with non-data frames; or it can be specified that the last two payload blocks in each OPU multiframe are fixedly inserted with non-data frames, etc. And, in practical applications, the non-data frames can include IDLE frames, customer fault frames, keep-alive frames, maintenance status frames, OAM frames, etc. For example, see Figure 5 As shown, in the figure, OAM frames are fixedly inserted into the first payload block and the second payload block in each OPU multiframe. The two inserted OAM frames are respectively denoted as PB-OAM1 and PB-OAM2. The remaining 236 payload blocks in each OPU multiframe are used to transmit OSU data, marked as PB#1~PB#236. Among them, PB-OAM1 can be used to transmit the multiplexing structure identifier corresponding to the first 118 payload blocks among the 236 payload blocks, and PB-OAM2 can be used to transmit the multiplexing structure identifier corresponding to the last 118 payload blocks among the 236 payload blocks.

[0032] Exemplarily, see Figure 8 As shown, as an alternative embodiment, step A2 specifically includes: A201. During a transmission cycle, the source end counts and numbers all OPU superframes, and places the superframe count numbers of each OPU superframe into two non-data frames. It can be understood that, due to the redefinition of the P value in this embodiment, for various ODU types, there are N OPU superframes in a transmission cycle. Therefore, in practical applications, when counting and numbering the OPU superframes, the counting range of the superframe count numbers can be 0 to (N - 1). Moreover, when placing the superframe count numbers of each OPU superframe into two non-data frames, they can be specifically placed in specific positions of the two non-data frames. For example, assuming the two non-data frames are two OAM frames, denoted as PB-OAM1 and PB-OAM2 respectively, the superframe count numbers can be inserted into the MFGI fields of PB-OAM1 and PB-OAM2.

[0033] A202. Using the superframe count number as the address, the source end obtains the channel numbers of the OSU carried by the 236 payload blocks of each OPU superframe (i.e., the multiplexing structure identifier corresponding to each OPU superframe) from the multiplexing structure configuration table, and places them into two non-data frames of each OPU superframe. In practical applications, the channel numbers of the OSU carried by the 236 payload blocks of each OPU superframe can be evenly placed into two non-data frames. For example, assuming the two non-data frames are two OAM frames, denoted as PB-OAM1 and PB-OAM2 respectively, the channel numbers of the OSU carried by the first 118 payload blocks of the OPU superframe can be placed into PB-OAM1, and the channel numbers of the OSU carried by the last 118 payload blocks of the OPU superframe can be placed into PB-OAM2.

[0034] A203. Insert the two processed non-data frames into two specified payload blocks reserved for the corresponding OPU superframe. In practical applications, according to the reserved payload block indication (such as the PB-OAM1 payload block indication and the PB-OAM2 payload block indication), the processed non-data frames (such as the PB-OAM1 frame and the PB-OAM2 frame) can be quickly inserted into the two specified reserved payload blocks.

[0035] Furthermore, to facilitate the sink end to quickly identify the two payload blocks inserted with two non-data frames, as an optional implementation manner, the source end also inserts a non-data frame payload block identifier into the two non-data frames, which is used to indicate that this payload block is a payload block inserted with a non-data frame; for example, the non-data frame payload block identifier OT = 0111 can be defined to indicate that this payload block is a payload block inserted with a non-data frame, and is used to transmit the superframe count number of the OPU superframe and the multiplexing structure identifier corresponding to the OPU superframe.

[0036] Furthermore, to ensure the validity (correctness) of the information transmitted by two non-data frames (including the multiplex frame count number of the OPU multiplex frame and the multiplexing structure identifier corresponding to the OPU multiplex frame), as an optional implementation, the source end also inserts multiplex frame count number verification information and multiplexing structure identifier verification information into the two non-data frames. Among them, the multiplex frame count number verification information is the result of performing a CRC calculation on the multiplex frame count number, which is used by the sink end to verify the validity of the multiplex frame count number based on this information; the multiplexing structure identifier verification information is the result of performing a CRC calculation on the multiplexing structure identifier, which is used by the sink end to verify the validity of the multiplexing structure identifier based on this information. It can be understood that when performing the CRC calculation, the corresponding CRC type can be selected according to specific requirements, such as CRC-8, CRC-16, CRC-32, etc., which are not specifically limited in this embodiment. Moreover, in practical applications, the multiplexing structure identifiers carried in each non-data frame can be divided into multiple groups, and the corresponding multiplexing structure identifier verification information follows each group of multiplexing structure identifiers.

[0037] Exemplarily, referring to Figure 9 shown Figure 9 is a schematic structural diagram of two non-data frames as OAM frames in an example. As Figure 9 shown, OT = 0111 in the PB-OAM1 frame and the PB-OAM2 frame is the non-data frame payload block identifier; in the MFGI fields of the PB-OAM1 frame and the PB-OAM2 frame, the multiplex frame count number of the corresponding OPU multiplex frame is stored, and the result of performing a CRC-8 calculation on this multiplex frame count number (i.e., the multiplex frame count number verification information) follows the MFGI field. In addition, the channel numbers of the OSU carried by the first 118 payload blocks of the OPU multiplex frame (i.e., the multiplexing structure identifiers of the first 118 payload blocks) are stored in the corresponding fields of the PB-OAM1 frame, and the channel numbers of the OSU carried by the first 118 payload blocks are divided into two groups, with 59 channel numbers of the OSU carried by each group of 59 payload blocks, and the result of performing a CRC-32 calculation on the channel numbers of the OSU carried by these 59 payload blocks (i.e., the multiplexing structure identifier verification information corresponding to the 59 payload blocks) follows each group. Similarly, the channel numbers of the OSU carried by the last 118 payload blocks of the OPU multiplex frame (i.e., the multiplexing structure identifiers of the last 118 payload blocks) are stored in the corresponding fields of the PB-OAM2 frame, and the channel numbers of the OSU carried by the last 118 payload blocks are also divided into two groups, with 59 channel numbers of the OSU carried by each group of 59 payload blocks, and the result of performing a CRC-32 calculation on the channel numbers of the OSU carried by these 59 payload blocks (i.e., the multiplexing structure identifier verification information corresponding to the 59 payload blocks) also follows each group.

[0038] Through the above steps A1 to A2, the processing content of multiplexing OSU to OPU can be completed on the source side; on the sink side, only need to update the local multiple-frame count number and multiplexing structure identification configuration table according to the multiple-frame count number of the OPU multiple-frame carried in the non-data frame and the multiplexing structure identification corresponding to the OPU multiple-frame, and look up the multiplexing structure identification configuration table by using the payload block count number and the multiple-frame count number in the multiple-frame as addresses, then the OSU service channel number corresponding to the payload block can be obtained. Adopting the solution of the embodiment of the present application can effectively ensure the consistency of the multiplexing structures of P payload blocks within the transmission period obtained by the source side and the sink side, prevent the situation of incorrect correspondence of the OSU service channels, thereby avoiding crosstalk between channels, and can effectively improve the anti-interference ability between channels; moreover, adopting the solution of the embodiment of the present application, even when an error is detected by the OSU frame CRC-8, it does not need to rely on TPN and will not actively discard packets. By looking up the multiplexing structure identification configuration table by using the payload block count number and the multiple-frame count number in the multiple-frame as addresses, the error channel number can be quickly located, thereby reducing the time for channel alarm detection.

[0039] In a second aspect, the embodiment of the present application further provides a method for multiplexing OSU to OPU.

[0040] In one embodiment, refer to Figure 10 as shown in Figure 10 which is a schematic flowchart of an embodiment of the method for multiplexing OSU to OPU in the second aspect of the present application. As Figure 10 shown, a method for multiplexing OSU to OPU includes: Step B1: After the sink side completes the framing of the OPU multiple-frame (i.e., determines the boundary of the OPU multiple-frame) through the PBP in the OPU overhead, perform a payload block count numbering on the payload blocks mapped with OSU services within the OPU multiple-frame, and extract two non-data frames from two specified payload blocks of the OPU multiple-frame, and update the local multiple-frame count number and multiplexing structure identification configuration table according to the multiple-frame count number of the OPU multiple-frame carried in the two non-data frames and the multiplexing structure identification corresponding to the OPU multiple-frame.

[0041] It can be understood that, different from the prior art, after receiving the OPU frame transmitted from the source end, the sink end extracts the non-data frames in the specified two payload blocks from each OPU multiplex frame, and obtains the multiplex frame count number of the OPU multiplex frame carried therein and the multiplexing structure identification corresponding to the OPU multiplex frame from the non-data frames; and by synchronously updating the local multiplex frame count number and multiplexing structure identification configuration table, the sink end can be made to be consistent with the source end in terms of the multiplex frame count number and the multiplexing structure identification configuration table, so as to ensure that when subsequently using the payload block count number and multiplex frame count number in the multiplex frame as addresses to look up the multiplexing structure identification configuration table, the correct and valid OSU service channel number can be obtained.

[0042] In practical applications, after the sink-end chip is powered on, the software configures the size of the local multiplexing structure identification configuration table according to the ODU type. Moreover, when the sink end extracts two non-data frames from the specified two payload blocks of the OPU multiplex frame, it can, through a way pre-negotiated with the source end, know in advance the two specified payload blocks in the OPU multiplex frame. For example, through a way pre-negotiated with the source end, the sink end can know in advance that the first payload block and the second payload block in each OPU multiplex frame are the two specified payload blocks where non-data frames are fixedly inserted, then the sink end can extract two non-data frames from the first payload block and the second payload block in each OPU multiplex frame. Or in some embodiments, the sink end can quickly identify the two specified payload blocks where two non-data frames are inserted through the non-data frame payload block identification carried in the non-data frames.

[0043] Further, as an optional embodiment, in step B1, the sink end performs framing of the OPU multiplex frame through the PBP in the OPU overhead, which specifically includes: 1. Extract the PBP in the OPU overhead and compare it with the PBP received last time. If it is found through comparison that the received PBP cycles in the order of {0, 64, 128}, it is determined that the comparison passes; otherwise, it is determined that the comparison fails. 2. If it is determined that the comparison passes continuously for 3 times, set the preset multiplex frame framing synchronization flag to 1; if the comparison fails continuously for 3 times, set the preset multiplex frame framing synchronization flag to 0. It can be understood that only when the multiplex frame framing synchronization flag is set to 1 will the sink end perform subsequent operations such as payload block count number and non-data frame extraction.

[0044] Further, as an optional implementation, if frame count number check information and multiplexing structure identifier check information are inserted into the two non-data frames extracted, the frame count number check information is the result of performing a CRC calculation on the frame count number, and the multiplexing structure identifier check information is the result of performing a CRC calculation on the multiplexing structure identifier, then in step B1, two non-data frames are extracted from two specified payload blocks of the OPU frame, and the local frame count number and multiplexing structure identifier configuration table are updated through the frame count number of the OPU frame carried in the two non-data frames and the multiplexing structure identifier corresponding to the OPU frame. Specifically, it includes: 1. The sink extracts the frame count number and its corresponding frame count number check information from the two non-data frames, and respectively checks the validity of the frame count numbers in the two non-data frames. Specifically, during the check, the result of performing a corresponding CRC calculation on the frame count number can be compared with the result in the corresponding frame count number check information. If the two are the same, it is verified as valid; otherwise, it is verified as invalid. Similarly, it can be understood that when performing the CRC calculation, the corresponding CRC type can be selected according to the same requirements as the source end, such as CRC-8, CRC-12, CRC-16, etc. This embodiment does not make specific limitations.

[0045] 2. If the frame count numbers in the two non-data frames are both verified as valid and the frame count numbers in the two non-data frames are the same, set the preset frame comparison equal flag to 1, and at the same time update the local frame count number; otherwise, set the frame comparison equal flag to 0. 3. The sink extracts the multiplexing structure identifier and its corresponding frame count number check information from the two non-data frames, and respectively checks the validity of the multiplexing structure identifiers in the two non-data frames. Specifically, during the check, according to the actual grouping situation, the result of performing a corresponding CRC calculation on each group of multiplexing structure identifiers can be compared with the result in the frame count number check information corresponding to the group. If the two are the same, it is verified as valid; otherwise, it is verified as invalid. For example, as Figure 9 shown, assuming that there are two groups of multiplexing structure identifiers of 59 payload blocks and the corresponding CRC-32 results for two groups in each OAM frame, then the result of performing a corresponding CRC-32 calculation on the multiplexing structure identifiers of each group of 59 payload blocks is compared with the extracted CRC-32 result of the group. If the two are the same, it is verified that the multiplexing structure identifiers of the 59 payload blocks in the group are valid; otherwise, it is verified as invalid. 4. When the frame comparison equal flag is 1, update the verified valid multiplexing structure identifier to the multiplexing structure identifier configuration table.

[0046] Step B2. The sink looks up the multiplexing structure identifier configuration table using the payload block count number and frame count number in the frame as addresses to obtain the OSU service channel number corresponding to the payload block.

[0047] Through the above steps B1 to B2, the processing content of realizing the OSU multiplexing to the OPU on the sink side can be completed. It can be seen from the above content that the sink side can update the local multiplex frame count number and multiplexing structure identification configuration table according to the multiplex frame count number of the OPU multiplex frame carried in the non-data frame and the multiplexing structure identification corresponding to the OPU multiplex frame; and by using the payload block count number in the multiplex frame and the updated multiplex frame count number as addresses to look up the updated multiplexing structure identification configuration table, the OSU service channel number corresponding to the payload block can be obtained. The entire implementation process can not only prevent the situation of incorrect correspondence of the OSU service channels, thus avoiding crosstalk between channels, but also effectively improve the anti-interference ability between channels; moreover, adopting the solution of the embodiment of the present application, even when an error is detected by the OSU frame CRC-8, it does not need to rely on the TPN and will not actively discard packets. By looking up the table through the payload block count number and the multiplex frame count number, the error channel number can be quickly located, thereby reducing the time for channel alarm detection.

[0048] In addition, it can also be understood that in the CCSA standard, it is defined that the generation or disappearance of the OSU loss of frame (LOF) is judged by not receiving or receiving a valid OSU frame within 3 ms, and its detection logic is complex and inaccurate, and the detection time is long; while after adopting the solution of the embodiment of the present application, the sink side can judge by detecting whether a valid OSU frame is received within the transmission period (about 590 us), which can speed up the detection time of the OSU LOF and simplify its generation logic, facilitate the generation of maintenance status frames faster, and reduce the time of OSU disconnection.

[0049] In a third aspect, the embodiment of the present application further provides a source end device for implementing the method in the first aspect of the embodiment.

[0050] In one embodiment, referring to Figure 11 as shown, Figure 11 is a schematic diagram of the functional modules of an embodiment of the source end device of the present application. As Figure 11 shown, a source end device includes: an OSU mapping module and a non-data frame insertion module.

[0051] Among them, the OSU mapping module is used to: map the OSU service to the payload blocks of the OPU; during the mapping process, take every three OPU frames as an OPU multiplex frame, reserve two specified payload blocks in the payload area of each OPU multiplex frame, map the OSU services within the transmission period to the remaining P - 2N payload blocks, and obtain the corresponding multiplexing structure identification; where P is the P value of various redefined ODU types, which satisfies that P is an integer multiple of 238 of N; the obtained multiplexing structure identification is the OSU service channel number corresponding to the payload block count number of the P - 2N payload blocks.

[0052] Specifically, the OSU mapping module maps OSU services into the payload blocks of the OPU, including the following operations: 1. The OSU mapping module configures the number of payload blocks P within the transmission period according to the redefined P value based on the ODU type; takes every three OPU frames as an OPU multiplex frame, reserves two specified payload blocks in the payload area of each OPU multiplex frame, calculates the distribution positions of each OSU service within the remaining P - 2N payload blocks during the transmission period according to a preset algorithm and rules, and writes them into the multiplexing structure identification configuration table. For example, assuming the ODU type is ODU2, the number of payload blocks P within the transmission period can be configured as P = 3808 according to the redefined P value; taking every three OPU frames as an OPU multiplex frame, there are a total of 3808÷238 = 16 OPU multiplex frames. Reserve the first and second payload blocks in the payload area of each OPU multiplex frame, and use a software or hardware homogenization algorithm to calculate the distribution positions of each OSU service within 3808 - 2×16 = 3776 payload blocks during the transmission period, and write them into the multiplexing structure identification configuration table.

[0053] 2. After the OSU mapping module determines the order of the three OPU frames and the boundaries of the payload blocks by inserting 0, 64, and 128 into the OPU multiplex frame overhead PBP respectively, it performs payload block counting and numbering on the P - 2N payload blocks where the OSU service is located within the period with a period of P - 2N. For example, assuming the ODU type is ODU2, a multiplex frame structure of OPU2 is generated, as Figure 5 shown. The payload of every three OPU2 frames can just be divided into 238 payload blocks. Insert 0 into the PBP of the first OPU2 frame, and the first byte of its payload area is just the first byte of the 192 - byte payload block; insert 64 into the PBP of the second OPU2 frame; insert 128 into the PBP of the third OPU2 frame, and the last byte of its payload area is just the last byte of the payload block. Perform payload block counting and numbering on the 3776 payload blocks during the transmission period, and the counting range is 0 to 3775.

[0054] 3. The OSU mapping module looks up the multiplexing structure identification configuration table using the payload block counting number to obtain the OSU service channel number corresponding to the payload block; if there is OSU service data that has arrived in the OSU service channel corresponding to the payload block, load the data into the payload block; if there is no OSU service data arriving in the OSU service channel corresponding to the payload block, load the IDLE frame into the payload block for filling.

[0055] The non-data frame insertion module is used for: inserting two non-data frames into two specified payload blocks reserved in each OPU complex frame, where the two non-data frames carry the complex frame count number of the OPU complex frame and the multiplexing structure identifier corresponding to the OPU complex frame; wherein, the complex frame count number and the multiplexing structure identifier are used by the sink end to update the local complex frame count number and multiplexing structure identifier configuration table, and by using the payload block count number and the complex frame count number within the complex frame as addresses to look up the multiplexing structure identifier configuration table to obtain the OSU service channel number corresponding to the payload block.

[0056] Specifically, the non-data frame insertion module inserts two non-data frames into two specified payload blocks reserved in each OPU complex frame, including the following operations: 1. The non-data frame insertion module counts and numbers all OPU complex frames within one transmission cycle, and places the complex frame count number of each OPU complex frame into the two non-data frames. For example, assuming the ODU type is ODU2 and the two non-data frames are both OAM frames, denoted as PB-OAM1 and PB-OAM2 respectively, then within one transmission cycle, all OPU complex frames are counted and numbered, and the counting range is 0 to 15; and the complex frame count number of each OPU complex frame can be placed into the MFGI field in the corresponding PB-OAM1 and PB-OAM2.

[0057] 2. The non-data frame insertion module uses the complex frame count number as the address to obtain the channel numbers of the OSU carried by the 236 payload blocks of each OPU complex frame (i.e., the multiplexing structure identifier corresponding to each OPU complex frame) from the multiplexing structure configuration table, and places it into the two non-data frames of each OPU complex frame. For example, as Figure 9 shown, the channel numbers of the OSU carried by the first 118 payload blocks of the OPU complex frame can be placed into PB-OAM1, and the channel numbers of the OSU carried by the last 118 payload blocks of the OPU complex frame can be placed into PB-OAM2.

[0058] 3. The non-data frame insertion module inserts the two non-data frames after the above processing into the two specified payload blocks reserved in the corresponding OPU complex frame. For example, insert the processed PB-OAM1 frame and PB-OAM2 frame into the first and second payload blocks of the OPU complex frame respectively.

[0059] In practical applications, in order to ensure the validity (correctness) of the information transmitted by two non-data frames (including the frame count number of the OPU multiframe and the multiplexing structure identifier corresponding to the OPU multiframe), the non-data frame insertion module may also insert frame count number verification information and multiplexing structure identifier verification information into the two non-data frames. For example, still taking the above ODU type as ODU2 and both non-data frames as OAM frames, when the non-data frame insertion module places the frame count number of each OPU multiframe into the MFGI field in the corresponding PB-OAM1 and PB-OAM2, it will also calculate the CRC-8 of the frame count number in the MFGI field and insert the calculation result into the OAM frame as the frame count number verification information; in addition, when the non-data frame insertion module places the channel numbers of the OSU carried by 236 payload blocks of each OPU multiframe (i.e., the multiplexing structure identifier corresponding to each OPU multiframe) into the two OAM frames of each OPU multiframe, the channel numbers of the OSU carried by 236 payload blocks can be divided into 4 groups, with 59 OSU channel numbers in each group, and the CRC-32 will be calculated respectively, and then inserted in the format of 59 OSU channel numbers in a group followed by a corresponding CRC-32 calculation result, as Figure 9 shown.

[0060] It should be noted that the various change methods and other specific examples in the foregoing method embodiments of multiplexing OSU into OPU are equally applicable to the source device in this embodiment. Through the detailed description of the foregoing method, those skilled in the art can clearly know the implementation method of the source device in this embodiment. Therefore, for the sake of brevity of the specification, it will not be elaborated here.

[0061] Fourthly, the embodiment of the present application further provides a sink device for implementing the method in the second embodiment.

[0062] In one embodiment, referring to Figure 12 shown, Figure 12 is a schematic diagram of the functional modules of an embodiment of the sink device of the present application. As Figure 12 shown, a sink device includes: a multiframe framing module, a non-data frame extraction module, and a multiplexing structure identifier look-up table module.

[0063] Among them, the multiframe framing module is used to: complete the framing of the OPU multiframe through the PBP in the OPU overhead.

[0064] The non-data frame extraction module is used for: after the multi-frame framing module completes the framing of the OPU multi-frame, counting and numbering the payload blocks mapped with OSU services within the OPU multi-frame, and extracting two non-data frames from two specified payload blocks of the OPU multi-frame, and updating the local multi-frame count number and the multiplexing structure identification configuration table through the multi-frame count number of the OPU multi-frame carried in the two non-data frames and the multiplexing structure identification corresponding to the OPU multi-frame.

[0065] The multiplexing structure identification look-up table module is used for: looking up the multiplexing structure identification configuration table by using the payload block count number and the multi-frame count number within the multi-frame as addresses to obtain the OSU service channel number corresponding to the payload block.

[0066] Further, in practical applications, if the two non-data frames extracted also insert the multi-frame count number verification information and the multiplexing structure identification verification information, the multi-frame count number verification information is the result of performing CRC calculation on the multi-frame count number, and the multiplexing structure identification verification information is the result of performing CRC calculation on the multiplexing structure identification, then the non-data frame extraction module extracts two non-data frames from two specified payload blocks of the OPU multi-frame, and updates the local multi-frame count number and the multiplexing structure identification configuration table through the multi-frame count number of the OPU multi-frame carried in the two non-data frames and the multiplexing structure identification corresponding to the OPU multi-frame, which specifically includes the following operations: 1. The non-data frame extraction module extracts the multi-frame count number and its corresponding multi-frame count number verification information in the two non-data frames, and respectively verifies the validity of the multi-frame count numbers in the two non-data frames; for example, taking the Figure 9 shown OAM frame as an example, the multi-frame count number can be extracted from the MFGI field of the PB-OAM1 frame and the PB-OAM2 frame, and the corresponding CRC-8 calculation result can be extracted after the MFGI field; compare the result after performing CRC-8 calculation on the extracted multi-frame count number with the extracted calculation result, if the two are the same, it is verified as valid, otherwise it is verified as invalid; 2. If the multi-frame count numbers in the two non-data frames are both verified to be valid and the multi-frame count numbers in the two non-data frames are the same, the non-data frame extraction module sets the preset multi-frame comparison equal flag to 1, and at the same time updates the local multi-frame count number; otherwise, the multi-frame comparison equal flag is set to 0; 3. The non-data frame extraction module extracts the multiplexing structure identification and its corresponding multi-frame count number verification information in the two non-data frames, and respectively verifies the validity of the multiplexing structure identifications in the two non-data frames; specifically during verification, the result after performing corresponding CRC calculation on each group of multiplexing structure identifications according to the actual grouping situation can be compared with the result in the multi-frame count number verification information corresponding to the grouping, if the two are the same, it is verified as valid, otherwise it is verified as invalid; for example, asFigure 9 As shown, assuming that there are two sets of multiplexing structure identifiers for 59 payload blocks and the corresponding CRC-32 results in each OAM frame, the result after performing the corresponding CRC-32 calculation on the multiplexing structure identifier of each set of 59 payload blocks is compared with the CRC-32 result of this set. If the two are the same, it is verified that the multiplexing structure identifier of this set of 59 payload blocks is valid; otherwise, it is verified as invalid. 4. When the comparison equal flag of the multiple frames is 1, the non-data frame extraction module updates the verified valid multiplexing structure identifier to the multiplexing structure identifier configuration table.

[0067] Similarly, it should be noted that the various change methods and other specific examples in the foregoing method embodiments of multiplexing OSU to OPU also apply to the sink device of this embodiment. Through the detailed description of the foregoing method, those skilled in the art can clearly know the implementation method of the sink device in this embodiment. Therefore, for the sake of simplicity of the specification, it will not be elaborated here.

[0068] Fifthly, the embodiment of the present invention also provides a system for multiplexing OSU to OPU.

[0069] In one embodiment, referring to Figure 13 as shown, Figure 13 is a schematic architecture diagram of an embodiment of the system for multiplexing OSU to OPU of this application. As Figure 13 shown, a system for multiplexing OSU to OPU includes a source device as in the embodiment of the third aspect and a sink device as in the embodiment of the fourth aspect.

[0070] Note: The terms "including" and "having" and any variations thereof in the specification, claims, and the above-mentioned drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products, or devices. The descriptions such as "first", "second", and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit that "first", "second", and "third" are of different types.

[0071] In the description of the embodiments of this application, terms such as "exemplary", "for example", or "for instance" are used to represent examples, illustrations, or explanations. Any embodiment or design solution described as "exemplary", "for example", or "for instance" in the embodiments of this application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Exactly, the use of terms such as "exemplary", "for example", or "for instance" is intended to present relevant concepts in a specific manner.

[0072] In some of the processes described in the embodiments of this application, there are multiple operations or steps that appear in a specific order. However, it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of this application or may be executed in parallel. The serial numbers of the operations are only used to distinguish different operations, and the serial numbers themselves do not represent any execution order. Additionally, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0073] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases, the former is a better implementation method. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium as described above (such as ROM / RAM, magnetic disk, optical disc), and includes several instructions for causing a terminal device to execute the methods described in the various embodiments of this application.

[0074] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application. Any equivalent structural or equivalent process transformations made by using the content of the specification and drawings of this application, or directly or indirectly applied in other related technical fields, are equally included in the patent protection scope of this application.

Claims

1. A method for multiplexing OSU into OPU, characterized in that, The method includes: The source end maps the OSU service into the payload blocks of the OPU; during the mapping process, every three OPU frames are taken as an OPU multiplex frame, two specified payload blocks are reserved in the payload area of each OPU multiplex frame, the OSU services within the transmission period are mapped into the remaining P - 2N payload blocks, and the corresponding multiplexing structure identifier is obtained; where P is the P value of various redefined ODU types, and P is an integer multiple of 238 of N. The source end inserts two non - data frames into the two specified payload blocks reserved in each OPU multiplex frame, and the two non - data frames carry the multiplex frame count number of this OPU multiplex frame and the multiplexing structure identifier corresponding to this OPU multiplex frame; where the multiplex frame count number and the multiplexing structure identifier are used for the sink end to update the local multiplex frame count number and multiplexing structure identifier configuration table according to this information, and by using the payload block count number and the multiplex frame count number within the multiplex frame as addresses to look up the multiplexing structure identifier configuration table, the OSU service channel number corresponding to the payload block is obtained.

2. The method for multiplexing OSU to OPU as claimed in claim 1, wherein The source end mapping the OSU service into the payload blocks of the OPU includes: The source end configures the number P of payload blocks within the transmission period according to the ODU type according to the redefined P value; takes every three OPU frames as an OPU multiplex frame, reserves two specified payload blocks in the payload area of each OPU multiplex frame, calculates the distribution positions of each OSU service within the transmission period in the remaining P - 2N payload blocks according to a preset algorithm and rules, and writes them into the multiplexing structure identifier configuration table. After the source end determines the order of the three OPU frames and the boundaries of the payload blocks by inserting 0, 64, and 128 into the OPU frame overhead PBP respectively, it numbers the P - 2N payload blocks where the OSU services are located within the period with a period of P - 2N, and uses the payload block count number to look up the multiplexing structure identifier configuration table to obtain the OSU service channel number corresponding to the payload block. If there is OSU service data that has arrived at the OSU service channel corresponding to the payload block, the data is loaded into the payload block; if there is no OSU service data arriving at the OSU service channel corresponding to the payload block, an IDLE frame is loaded into the payload block for filling.

3. The method for multiplexing OSU to OPU according to claim 1, characterized in that, The source end inserting two non - data frames into the two specified payload blocks reserved in each OPU multiplex frame includes: The source end numbers all the OPU multiplex frames within a transmission period, and places the multiplex frame count number of each OPU multiplex frame into the two non - data frames. The source end takes the multiplex frame count number as the address, obtains the channel numbers of the OSU carried by the 236 payload blocks of each OPU multiplex frame from the multiplexing structure configuration table, and places them into the two non - data frames of each OPU multiplex frame. The two processed non - data frames are inserted into the two specified payload blocks reserved in the corresponding OPU multiplex frame.

4. The method for multiplexing OSU to OPU according to claim 1, characterized in that, The method further includes: The source end inserts multiplex frame count number verification information and multiplexing structure identifier verification information into the two non - data frames. The multiple-frame count number verification information is the result of performing a CRC calculation on the multiple-frame count number, and is used by the sink end to verify the validity of the multiple-frame count number based on this information; The multiplexing structure identification verification information is the result of performing a CRC calculation on the multiplexing structure identification, and is used by the sink end to verify the validity of the multiplexing structure identification based on this information.

5. The method for multiplexing OSU to OPU according to claim 1, wherein The method further includes: the source end inserts a non-data frame payload block identifier into the two non-data frames, which is used to indicate that the payload block is a payload block inserted with a non-data frame.

6. A method for multiplexing OSU into OPU, characterized in that, The method includes: After the sink end completes the framing of the OPU multiple-frame through the PBP in the OPU overhead, it counts the payload blocks mapped with the OSU service within the OPU multiple-frame, extracts two non-data frames from the specified two payload blocks of the OPU multiple-frame, and updates the local multiple-frame count number and multiplexing structure identification configuration table through the multiple-frame count number of this OPU multiple-frame and the multiplexing structure identification corresponding to this OPU multiple-frame carried in the two non-data frames; The sink end looks up the multiplexing structure identification configuration table by using the payload block count number and multiple-frame count number within the multiple-frame as addresses to obtain the OSU service channel number corresponding to the payload block.

7. The method for multiplexing OSU into OPU according to claim 6, characterized in that, If the two non-data frames extracted also insert the multiple-frame count number verification information and the multiplexing structure identification verification information, the sink end will verify the validity of the extracted multiple-frame count number and multiplexing structure identification based on this information; and only when the verification is valid, will it update the local multiple-frame count number and multiplexing structure identification configuration table.

8. A source device for implementing the method according to any one of claims 1 to 5, characterized in that, The source end device includes an OSU mapping module and a non-data frame insertion module; The OSU mapping module is used to: map the OSU service into the payload blocks of the OPU; During the mapping process, every three OPU frames are used as an OPU multiple-frame, two specified payload blocks are reserved in the payload area of each OPU multiple-frame, the OSU services within the transmission period are mapped into the remaining P - 2N payload blocks, and the corresponding multiplexing structure identification is obtained; where P is the P value of various redefined ODU types, and P satisfies that P is an integer multiple of 238N; The non-data frame insertion module is used to: insert two non-data frames into the two specified payload blocks reserved in each OPU multiple-frame, and the two non-data frames carry the multiple-frame count number of this OPU multiple-frame and the multiplexing structure identification corresponding to this OPU multiple-frame; where the multiple-frame count number and the multiplexing structure identification are used by the sink end to update the local multiple-frame count number and multiplexing structure identification configuration table based on this information, and look up the multiplexing structure identification configuration table by using the payload block count number and multiple-frame count number within the multiple-frame as addresses to obtain the OSU service channel number corresponding to the payload block.

9. A host device for implementing the method according to any one of claims 6 or 7, characterized in that, The sink end device includes a multiple-frame framing module, a non-data frame extraction module, and a multiplexing structure identification look-up module; The multiple-frame framing module is used to: complete the framing of the OPU multiple-frame through the PBP in the OPU overhead; The non-data frame extraction module is used for: after the multi-frame framing module completes the framing of the OPU multi-frame, performing payload block counting and numbering on the payload blocks mapped with OSU services within the OPU multi-frame, and extracting two non-data frames from two specified payload blocks of the OPU multi-frame, and updating the local multi-frame count number and multiplexing structure identification configuration table through the multi-frame count number of the OPU multi-frame carried in the two non-data frames and the multiplexing structure identification corresponding to the OPU multi-frame; The multiplexing structure identification look-up table module is used for: looking up the multiplexing structure identification configuration table by using the payload block count number and multi-frame count number within the multi-frame as addresses to obtain the OSU service channel number corresponding to the payload block.

10. A system for multiplexing OSU into OPU, characterized in that: The system includes the source device as described in claim 8 and the sink device as described in claim 9.

Images