Path establishment method, network node, and storage medium

Abstract

The present application provides a path establishment method, a network node, and a storage medium. The path establishment method comprises: a source node acquiring bandwidth indication information and an outgoing time slot port number corresponding to the present node; determining an outgoing time slot on the basis of the bandwidth indication information; sending to a downstream node a first service layer signal comprising an MSI field, wherein the MSI field carries information about a correspondence between the outgoing time slot and the outgoing time slot port number; sending to the downstream node a first path configuration message carrying the outgoing time slot port number corresponding to the present node; and receiving a first path configuration response message sent by the downstream node on the basis of the first path configuration message and the first service layer signal.

Description

Path establishment method, network node and storage medium

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202311241504.8 and application date September 22, 2023, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this application as a reference. Technical Field

[0003] The present application relates to the field of communication technology, and in particular to a path establishment method, a network node, and a storage medium. Background Art

[0004] Optical Transport Network (OTN) technology is the core technology of transport networks, used for the flexible scheduling and management of high-capacity services. The OTN standard defines the multiplexing relationship between optical channel data units (ODUs). Based on this multiplexing relationship, ODUs are divided into low-order ODUs and high-order ODUs. Low-order ODUs can be multiplexed into high-order ODUs, where the high-order ODUs serve as the service layer and the low-order ODUs serve as the client layer.

[0005] During ODU multiplexing, the standard designs a verification mechanism for the time slot mapping relationship between low-order ODUs in the higher-order ODUk link. All time slots of the same low-order ODU need to be identified by the same Tributary Port Number (TPN) in the higher-order ODU. The source end of the high-order ODU link between two nodes sets the TPN to the Multiplex Structure Identifier (MSI) field in the higher-order ODU overhead. The sink end reads the TPN from the MSI and compares it with the expected MSI.

[0006] At the network level, ODU distributed control plane service path control uses the Generalized Multi-Protocol Label Switching (GMPLS) signaling of the Automatic Switching Optical Network (ASON) and the Resource Reservation Protocol (RSVP) technology based on GMPLS extensions to establish service connection paths. The specific timeslot occupancy representation on each port adopts the RFC7139 representation method, that is, the mapping information of the low-order ODU to the high-order ODU. The TPN needs to be set in the MSI field of the high-order OPUk overhead, and its timeslot positioning information corresponds to the indication in the timeslot mapping table. However, with the development of OTN technology, the timeslot mapping tables carried in signaling have become increasingly long, which is not conducive to efficient signaling transmission and parsing, and reduces the speed of path establishment.

[0007] Summary of the Invention

[0008] The embodiments of the present application provide a path establishment method, a network node, and a storage medium, which can improve the establishment speed of service paths in an OTN network.

[0009] In a first aspect, an embodiment of the present application provides a path establishment method, which is applied to a source node, and the method includes: obtaining bandwidth indication information of a client layer signal of a service path to be established and an outgoing time slot port number corresponding to the current node; determining an outgoing time slot based on the bandwidth indication information; sending a first service layer signal to a downstream node, wherein the first service layer signal includes a multiplexing structure indication MSI field, and the MSI field carries correspondence information between the outgoing time slot and the outgoing time slot port number; sending a first path configuration message to the downstream node, wherein the first path configuration message carries the outgoing time slot port number corresponding to the current node; and receiving a first path configuration response message sent by the downstream node based on the first path configuration message and the first service layer signal.

[0010] In a second aspect, an embodiment of the present application provides a path establishment method, which is applied to an intermediate node, and the method includes: receiving a first path configuration message sent by an upstream node, wherein the first path configuration message carries the input time slot port number of the client layer signal of the service path to be established; receiving a first service layer signal sent by the upstream node, wherein the first service layer signal contains a multiplexing structure indication MSI field; determining the input time slot corresponding to the input time slot port number of the client layer signal according to the MSI subfield containing the input time slot port number in the MSI field; when confirming that the input time slot port number and the input time slot are both available, determining the output time slot and the output time slot port number corresponding to the client layer signal of this node; sending a second service layer signal to the downstream node, wherein the second service layer signal includes the MSI field, and the MSI field carries the correspondence information between the output time slot and the output time slot port number; sending a second path configuration message to the downstream node, wherein the second path configuration message carries the output time slot port number; receiving a second path configuration response message sent by the downstream node according to the second path configuration message and the second service layer signal.

[0011] In a third aspect, an embodiment of the present application provides a path establishment method, which is applied to a host node, and the method includes: receiving a path configuration message sent by an upstream node, wherein the path configuration message carries the input time slot port number of the client layer signal of the service path to be established; receiving a service layer signal sent by the upstream node, wherein the service layer signal includes a multiplexing structure indication MSI field; determining the input time slot corresponding to the input time slot port number of the client layer signal according to the MSI subfield containing the input time slot port number in the MSI field; determining a path configuration result according to the input time slot port number and the input time slot; and sending a path configuration response message to the upstream node according to the path configuration result.

[0012] In a fourth aspect, an embodiment of the present application provides a network node, comprising: one or more processors; a memory on which one or more programs are stored, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the path establishment method as described in the first aspect; or, implement the path establishment method as described in the second aspect; or implement the path establishment method as described in the third aspect.

[0013] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the path establishment method as described in the first aspect is implemented; or, the path establishment method as described in the second aspect is implemented; or, the path establishment method as described in the third aspect is implemented.

[0014] In an embodiment of the present application, a source node obtains bandwidth indication information of a client layer signal of a service path to be established and an outgoing time slot port number corresponding to the current node, and determines an outgoing time slot based on the bandwidth indication information. The source node then sends a first service layer signal including a multiplexing structure indication MSI field to a downstream node, the MSI field carrying information on the correspondence between the outgoing time slot and the outgoing time slot port number, and sends a first path configuration message carrying the outgoing time slot port number corresponding to the current node to the downstream node, and receives a first path configuration response message sent by the downstream node based on the first path configuration message and the first service layer signal; an intermediate node receives a first path configuration message sent by an upstream node, the first path configuration message carrying the incoming time slot port number of the client layer signal of the service path to be established, and receives a first service layer signal including a multiplexing structure indication MSI field sent by the upstream node, the intermediate node determines an incoming time slot corresponding to the incoming time slot port number of the client layer signal based on the MSI subfield containing the incoming time slot port number in the MSI field, and after confirming the incoming time slot port number and the incoming time slot port number, the intermediate node determines the incoming time slot corresponding to the incoming time slot port number of the client layer signal. When all slots are available, the intermediate node determines the outgoing time slot and outgoing time slot port number corresponding to the client layer signal of the node. The intermediate node then sends a second service layer signal including an MSI field to the downstream node, where the MSI field carries information about the correspondence between the outgoing time slot and the outgoing time slot port number, and sends a second path configuration message carrying the outgoing time slot port number to the downstream node, and receives a second path configuration response message sent by the downstream node based on the second path configuration message and the second service layer signal. The destination node receives a path configuration message sent by the upstream node, where the path configuration message carries the incoming time slot port number of the client layer signal of the service path to be established, and receives a service layer signal including a multiplexing structure indication MSI field sent by the upstream node. The destination node then determines the incoming time slot corresponding to the incoming time slot port number of the client layer signal based on the MSI subfield containing the incoming time slot port number in the MSI field. The destination node then determines the path configuration result based on the incoming time slot port number and the incoming time slot, and sends a path configuration response message to the upstream node based on the path configuration result. The embodiment of the present application uses the MSI field of the service layer to transmit the correspondence between the time slot and the time slot port number to the downstream node. Combined with the first path configuration message carrying the outgoing time slot port number, the signaling no longer carries the time slot mapping table, which can save the length of the signaling message, improve the efficiency of message transmission and parsing, and thus increase the speed of establishing the service path. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are used to provide a further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0016] FIG1 is a schematic diagram of establishing an RSVP connection provided by one embodiment of the present application;

[0017] FIG2 is a schematic diagram of a method for representing ODUk timeslot occupancy provided by an embodiment of the present application;

[0018] FIG3 is a schematic diagram of a 1.25G timeslot granularity MSI encoding format provided by one embodiment of the present application;

[0019] FIG4 is a flow diagram of a network architecture provided by an embodiment of the present application;

[0020] FIG5 is a flow chart of a path establishment method provided by an embodiment of the present application;

[0021] FIG6 is a flowchart of the sub-steps of step S120 in FIG5 ;

[0022] FIG7 is a flow chart of a path establishment method according to another embodiment of the present application;

[0023] FIG8 is a flow chart of a path establishment method according to another embodiment of the present application;

[0024] FIG9 is a flow chart of a path establishment method according to another embodiment of the present application;

[0025] FIG10 is a flow chart of a path establishment method according to another embodiment of the present application;

[0026] FIG11 is a flow chart of a path establishment method according to another embodiment of the present application;

[0027] FIG12 is a flow chart of a path establishment method according to another embodiment of the present application;

[0028] FIG13 is a flow chart of a path establishment method according to another embodiment of the present application;

[0029] FIG14 is a flow chart of a path establishment method according to another embodiment of the present application;

[0030] FIG15 is a schematic structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the technical solution of the present application, the path establishment method, path establishment device, electronic device, and computer-readable storage medium provided in the present application are described in detail below with reference to the accompanying drawings.

[0032] Example embodiments will be described more fully hereinafter with reference to the accompanying drawings, but the described example embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the scope of this application to those skilled in the art.

[0033] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] The terms used herein are used only to describe specific embodiments and are not intended to limit this application. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that when the terms "comprising" and / or "made of" are used in this specification, they specify the presence of features, wholes, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups thereof.

[0035] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0036] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the present application, and will not be interpreted as having an idealized or overly formal meaning, unless clearly defined in the examples of the present application.

[0037] Optical Transport Network (OTN) technology is the core technology of the transport network, used for flexible scheduling and management of high-capacity services. The OTN standard defines the multiplexing relationship between optical channel data units (ODUs). Based on the multiplexing relationship, ODUs are divided into low-order ODUs and high-order ODUs. Low-order ODUs can be multiplexed into high-order ODUs, where the high-order ODUs serve as the service layer and the low-order ODUs serve as the client layer. During the ODU multiplexing process, the standard designs a verification mechanism for the time slot mapping relationship of the low-order ODU in the high-order ODUk link. All time slots of the same low-order ODU need to be identified by the same time slot port number (TPN) in the high-order ODU. The source end of the high-order ODU link between two nodes sets the TPN in the multiplex structure identifier (MSI) field in the high-order ODU overhead. The destination end reads the TPN from the MSI and compares it with the expected MSI.

[0038] At the network level, the ODU distributed control plane service path control adopts the Generalized Multi-Protocol Label Switching (GMPLS) signaling method of the Automatic Switching Optical Network (ASON) and uses the Resource Reservation Protocol (RSVP) technology based on the GMPLS extension to establish a service connection path. Please refer to Figure 1, which shows a schematic diagram of the process of establishing an RSVP connection. As shown in Figure 1, node A, as the source node, sends an RSVP PATH message to node C. After receiving the RSVP PATH message, node B, as the intermediate node, forwards it to the next node according to the destination address carried in the RSVP PATH message. After receiving the RSVP PATH message, node C, as the target node, generates and returns an RSVP RESV message if it can meet the request. After receiving the RSVP RESV message, node B, as the intermediate node, allocates some resources to this service connection if it can meet the resource requirements in the RSVP RESV message. After receiving the RSVP RESV message, node A can establish the service connection path.

[0039] For the specific timeslot occupancy representation on each port, the representation method of RFC7139 is adopted, that is, the mapping information of the low-order ODU in the high-order ODU, such as the ODUk timeslot occupancy representation method shown in Figure 2. The TPN needs to be set to the MSI field of the high-order OPUk overhead, and its timeslot positioning information corresponds to the indication in the Bit Map (time slot mapping table). Among them, the OPUk overhead and MSI field are shown in Figure 3. For example, when using 1.25G time slot granularity mapping, taking the mapping of low-order ODUfle x (4 time slots) to high-order ODU4 (80 time slots) link as an example, the Bit Map (time slot mapping table) is 80 bits. Assuming that time slots 1, 3, 5, and 8 are allocated to low-order services and the allocated TPN is 3, the fields of 1, 3, 5, and 8 time slots corresponding to the MSI of the high-order OPU4 overhead need to be set to 3. As shown in Figure 3, the corresponding payload structure indication (Payload Structure Identifier, PSI) field Tributary Port# corresponding to TS1, 3, 5, and 8 is set to 3.

[0040] However, with the development of OTN technology, the timeslot mapping tables carried in signaling have become increasingly lengthy, hindering efficient signaling transmission and parsing and slowing down path establishment. For example, the 5G timeslot granularity of an 800G link using high-order ODUC8 is 160 bits, or 20 bytes. Low-order customer services, however, typically utilize up to 100G bandwidth using ODU4, occupying a maximum of 16 bits out of the 160 bits. This makes the bitmap representation very inefficient. For example, in fgOTN (fine grain OTN) technology, which carries small granularity data on the client side, the low-order fine grain flexible optical data unit (fg ODUflex) is mapped to the higher-order ODU0 (fgTS), ODU1 (fgTS), ODU2 (fgTS), or ODUflex (fgTS,n). The fgTS (Fine Grain Tributary Slot) represents the timeslot granularity, with n being an integer from 3 to 7. The ODUflex (fgTS,n) rate is n*ODU0, which is divided into n*119 fgTSs. ODUk (k = 0, 1, 2) is divided into 119, 238, and 952 fgTSs, respectively. If the RFC7139 label representation is still used, the maximum bit map required is 952 bits, occupying 119 bytes. When the fgODUflex path passes through many ports, the message length increases significantly, affecting signaling transmission time and parsing efficiency.

[0041] Based on this, embodiments of the present application provide a path establishment method, a network node, and a storage medium, which can increase the speed of establishing service paths in an OTN network.

[0042] Before introducing the technical solution of the embodiment of the present application, the network architecture of the embodiment of the present application is first exemplified. The network architecture of the embodiment of the present application includes a controller and a plurality of network nodes, and the controller is communicatively connected with each network node. Please refer to Figure 4, which is a schematic diagram of a network architecture provided by the embodiment of the present application. As shown in Figure 4, the network architecture includes a controller 100, a source node 200, an intermediate node 300, an intermediate node 301, an intermediate node 302, an intermediate node 303, an intermediate node 304, an intermediate node 305, and a destination node 400. The controller 100 is used to send a service path request message to the source node so that the source node 200 establishes a corresponding service path with the destination node 400 through the intermediate node.

[0043] The embodiment of the present application first proposes a path establishment method, which is applied to the source node. Please refer to Figure 5. Figure 5 shows a path establishment method provided by the embodiment of the present application. As shown in Figure 5, the method includes but is not limited to steps S110 to S150.

[0044] Step S110: Obtain bandwidth indication information of a client layer signal of a service path to be established and an outgoing timeslot port number corresponding to the current node.

[0045] It should be noted that the service path to be established refers to the connection path between the source node and the destination node. For example, as shown in Figure 4, the service path to be established is the service path between the source node 200 and the destination node 400. The links through which the service path passes can be the source node 200, the intermediate node 300, the intermediate node 301, the intermediate node 302, and the destination node 400.

[0046] It should be understood that the bandwidth indication information may include the transmission rate of the service path to be established, and the outgoing time slot port number corresponding to the current node refers to the time slot port number used by the client layer signal at the outgoing port of the current node.

[0047] Step S120: Determine a time slot according to the bandwidth indication information.

[0048] It should be understood that after obtaining the bandwidth indication information of the client layer information, the source node determines the downstream ODU time slot of the client layer signal according to the bandwidth indication information and completes the outbound port time slot allocation.

[0049] Step S130: Send a first service layer signal to the downstream node, wherein the first service layer signal includes a multiplexing structure indication MSI field, and the MSI field carries the correspondence information between the outgoing time slot and the outgoing time slot port number.

[0050] It can be understood that the source node sends the first service layer signal to the downstream node through the physical channel. The MSI field in the first service layer signal carries the correspondence information between the outgoing time slot and the outgoing time slot port number, including the outgoing time slot, the outgoing time slot port number and the correspondence between the two. By carrying the outgoing time slot and the outgoing time slot port number in the MSI field in the service layer signal, combined with the outgoing time slot port number in the first path configuration message, the connection is issued, avoiding the problem of the signaling signal being too long due to the signaling signal carrying the time slot mapping table under each port.

[0051] Step S140: Send a first path configuration message to the downstream node, wherein the first path configuration message carries the outgoing timeslot port number corresponding to the current node.

[0052] It should be understood that the source node can send a first path configuration message to the downstream node through a signaling channel, where the signaling channel can use an external data communication network (Data Communication Network), or a general communication channel (General Communication Channel, GCC) in the ODU overhead, or a communication channel formed by other fields. The embodiment of the present application is not limited here.

[0053] Step S150: Receive a first path configuration response message sent by the downstream node according to the first path configuration message and the first service layer signal.

[0054] It can be understood that after the source node sends the first service layer signal and the first path configuration message to the downstream node, the downstream node of the source node performs corresponding path configuration processing based on the first path configuration message and the first service layer signal, and sends a first path configuration response message based on the path configuration processing result.

[0055] In an embodiment of the present application, a source node obtains bandwidth indication information of a client layer signal of a service path to be established and an outgoing time slot port number corresponding to the current node, and determines an outgoing time slot based on the bandwidth indication information. The source node then sends a first service layer signal including a multiplexing structure indication MSI field to a downstream node, where the MSI field carries information on the correspondence between the outgoing time slot and the outgoing time slot port number, and sends a first path configuration message carrying the outgoing time slot port number corresponding to the current node to the downstream node. The source node receives a first path configuration response message sent by the downstream node based on the first path configuration message and the first service layer signal. The source node uses the MSI field of the service layer to convey the correspondence between the time slot and the time slot port number to the downstream node. Combined with the first path configuration message carrying the outgoing time slot port number, the signaling no longer carries a time slot mapping table, which can save the length of the signaling message, improve the efficiency of message transmission and parsing, and thus improve the speed of establishing the service path.

[0056] In some embodiments, please refer to FIG. 6 , which shows a sub-step flowchart of step S120 in FIG. 5 . As shown in FIG. 6 , step S120 further includes step S210 and step S220 .

[0057] Step S210: determining the number of time slots to be occupied by the client layer signal according to the bandwidth indication information.

[0058] Step S220: Determine an outgoing time slot corresponding to the number of time slots from the idle time slot resources of the current node.

[0059] It can be understood that the bandwidth indication information includes the transmission rate of the service path to be established, and the number of time slots that the client layer signal needs to occupy is determined based on the bandwidth indication information. For example, in fgOTN (fine grain OTN), the number of time slots mapped from the low-order fgODUflex to the high-order ODU is determined to be 4 based on the transmission rate in the bandwidth indication information, and the idle time slot resources 1, 3, 5, and 8 of this node are used as outgoing time slots to complete the downstream ODU time slot allocation.

[0060] In some embodiments, the first path configuration message further carries at least one of the following: a service identifier, routing list information, bandwidth indication information, a timeslot port number corresponding to a link through which the service path passes, source access port information, and sink access port information.

[0061] Exemplarily, as shown in FIG4 , the customer path to be established is the source node 200, the intermediate node 300, the intermediate node 301, the intermediate node 302, and the sink node 400. The service tag of the first path configuration message includes a service identifier, routing list information, bandwidth indication information, the time slot port number corresponding to the link through which the service path passes, the source access port information, and at least one of the sink access port information, wherein the service identifier is used to uniquely identify the service path; the source access port information is the source node port 2001, the sink node port information includes the sink node port 4002, and the access information is an Ethernet signal; the bandwidth indication information can be the transmission rate of the service path to be established, or the number of time slots occupied by the low-order ODU of the client layer mapped to the high-order ODU of the service layer; the routing list information includes the source node 200: the outgoing port 2002, the intermediate node 300: the ingoing port 3001, the outgoing port 3002 2. Intermediate node 301: ingress port 3011, egress port 3012, intermediate node 302: ingress port 3021, egress port 3022, destination node 400: ingress port 4001; the links through which the service path passes are source node 200, intermediate node 300, intermediate node 301, intermediate node 302, and destination node 400. Then, the time slot port numbers corresponding to the links through which the service path passes include the time slot port number corresponding to the egress port 2002 of source node 200 and the ingress port 3001 of intermediate node 300, which is 1; the time slot port number corresponding to the egress port 3002 of intermediate node 300 and the ingress port 3011 of intermediate node 301, which is 2; the time slot port number corresponding to the egress port 3012 of intermediate node 301 and the ingress port 3021 of intermediate node 302, which is 3; and the time slot port number corresponding to the egress port 3022 of intermediate node 302 and the ingress port 4001 of destination node 400, which is 4.

[0062] In some embodiments, please refer to Figure 7, which shows a path establishment method provided by an embodiment of the present application. As shown in Figure 7, before obtaining the bandwidth indication information of the client layer signal of the service path to be established and the outgoing time slot port number corresponding to the current node, the path establishment method also includes step S310.

[0063] Step S310: receiving a service path request message sent by a controller, wherein the service path request message indicates establishing a service path for carrying the client layer signal.

[0064] Step S110 in the path establishment method includes but is not limited to step S320.

[0065] Step S320: confirm the bandwidth indication information of the client layer signal and the outgoing timeslot port number corresponding to the current node according to the service path request message.

[0066] It should be understood that the controller can be an entity such as a network management server that can control and manage network nodes. As shown in Figure 4, the controller 100 is in communication with the source node 200, and the source node receives a service path request message sent by the controller. The service path request message is used to instruct the source node to establish a service path for carrying client layer signals. The source node obtains the bandwidth indication information of the client layer information of the service path to be established and the outgoing time slot port number corresponding to the node from the service path request message. Then, the source node constructs the service path according to the bandwidth indication information and the outgoing time slot port number.

[0067] In some embodiments, the service path request message carries at least one of the following: service identification, routing list information, bandwidth indication information, time slot port number corresponding to the link through which the service path passes, source access port information, and sink access port information.

[0068] It should be noted that the source node can pass the service path request message as the first path configuration message to the downstream node. The service path request message and the first path configuration message also carry the service identifier, routing list information, bandwidth indication information, the time slot port number corresponding to the link through which the service path passes, source access port information, and at least one of the destination access port information. For the carried information in the service path request message, please refer to the description in the first path configuration message, which will not be repeated here.

[0069] In some embodiments, please refer to Figure 8, which shows a path establishment method provided by an embodiment of the present application. As shown in Figure 8, after receiving the first path configuration response message sent by the downstream node according to the first path configuration message and the first service layer signal, the path establishment method also includes step S410.

[0070] Step S410: When the first path configuration response message indicates that the path configuration is successful, the client layer signal is carried in the third service layer signal through the outgoing time slot, and the third service layer signal is sent to the downstream node.

[0071] It should be noted that after the source node sends the first service layer signal and the first path configuration message to the downstream node, the downstream node of the source node performs corresponding path configuration processing according to the first path configuration message and the first service layer signal, and sends a first path configuration response message according to the path configuration processing result. When the first path configuration response message indicates that the path configuration is successful, that is, the service path is successfully established, the source node can carry the client layer signal in the third service layer signal through the outgoing time slot, that is, map the client layer low-order ODU to the service layer high-order ODU according to the outgoing time slot, and send the third service layer signal to the downstream node.

[0072] In a specific embodiment, the intermediate node, as a downstream node of the source node, receives a first path configuration message and a first service layer signal sent by the upstream node, and determines the input time slot corresponding to the input time slot port number of the client layer signal based on the MSI subfield containing the input time slot port number in the MSI field of the first service layer signal. The intermediate node then determines whether the input time slot port number and the input time slot are available. When the intermediate node confirms that both the input time slot port number and the input time slot are available, it determines the output time slot and the output time slot port number corresponding to the client layer signal of the node. The intermediate node then sends a second service layer signal to the downstream node, wherein the second service layer signal includes an MSI field, and the MSI field carries information on the correspondence between the output time slot and the output time slot port number, and sends a second path configuration message to the downstream node, wherein the second path configuration message carries the output time slot port number.

[0073] The sink node receives a path configuration message sent by an upstream node via a signaling channel. The path configuration message carries the inbound time slot port number of the service path to be established, and receives a service layer signal sent by the upstream node. The service layer signal includes a multiplexing structure indicator (MSI) field. The sink node determines the inbound time slot based on the MSI subfield containing the inbound time slot port number in the MSI field. The sink node determines the path configuration result based on the inbound time slot port number and the inbound time slot. The sink node then sends a path configuration response message to the upstream node based on the path configuration result. Each upstream node of the sink node then responds to the upstream node with the path configuration result hop by hop based on the ODU cross-connection configuration result of the sink node. Specifically, if the cross-connection configuration of the sink node fails, the sink node sends a path configuration response message to the upstream node indicating the path configuration failure. If the path configuration response message sent by the downstream node indicates that the path configuration failed, the sink node sends a path configuration response message to the upstream node indicating the path configuration failure. If the path configuration response message sent by the downstream node indicates that the path configuration was successful and the cross-connection configuration of the sink node is successful, the sink node sends a path configuration response message to the upstream node indicating that the path configuration was successful.

[0074] After receiving the path configuration response message indicating that the path configuration is successful, the source node can carry the client layer signal in the third service layer signal through the outgoing time slot and send the third service layer signal to the downstream node.

[0075] In some embodiments, please refer to Figure 9, which shows a path establishment method provided by an embodiment of the present application. As shown in Figure 9, after receiving the first path configuration response message sent by the downstream node based on the first path configuration message and the first service layer signal, the path establishment method also includes steps S510 to S540.

[0076] Step S510 : When the first path configuration response message indicates that the path configuration has failed and the cause of the path configuration failure is a timeslot port number conflict, a new timeslot port number is requested for the client layer signal for the link where the timeslot port number conflict occurs.

[0077] Step S520: Determine a new first path configuration message and a new first service layer signal according to the new timeslot port number.

[0078] Step S530: Send a new first path configuration message to the downstream node.

[0079] Step S540: Send a new first service layer signal to the downstream node.

[0080] It should be noted that after the source node sends the first service layer signal and the first path configuration message to the downstream node, the downstream node of the source node performs corresponding path configuration processing based on the first path configuration message and the first service layer signal, and sends a first path configuration response message based on the path configuration processing result. When the first path configuration response message indicates that the path configuration failed and the reason for the path configuration failure is a time slot port number conflict, the source node can re-request a new time slot port number for the client layer signal, determine a new first path configuration message and first service layer signal based on the new time slot port number, and then send the new first path configuration message and first service layer signal to the downstream node.

[0081] In a specific embodiment, the intermediate node acts as a downstream node of the source node, receives the first path configuration message and the first service layer signal sent by the upstream node, and determines the input time slot corresponding to the input time slot port number of the client layer signal based on the MSI subfield containing the input time slot port number in the MSI field of the first service layer signal. The intermediate node then determines whether the input time slot port number and the input time slot are available.

[0082] If the intermediate node determines that the input time slot port number is unavailable, it sends a first path configuration response message to the upstream node, indicating that the path configuration failed and the cause of the path configuration failure is a time slot port number conflict. Alternatively, if the intermediate node confirms that both the input time slot port number and the input time slot are available, it determines the client layer signal corresponding to the node's output time slot and output time slot port number. Further, if the intermediate node confirms that the output time slot port number is unavailable, it sends a first path configuration response message to the upstream node, indicating that the path configuration failed and the cause of the path configuration failure is a time slot port number conflict.

[0083] After the source node receives the first path configuration response message indicating that the path configuration has failed and the reason for the path configuration failure is a time slot port number conflict, it can request a new time slot port number for the client layer signal for the link where the time slot port number conflict occurs, and determine a new first path configuration message and a new first service layer signal based on the new time slot port number. The source node then sends the new first path configuration message to the downstream node and sends a new first service layer signal through the downstream node.

[0084] In some embodiments, please refer to Figure 10, which shows a path establishment method provided by an embodiment of the present application. As shown in Figure 10, after receiving the first path configuration response message sent by the downstream node based on the first path configuration message and the first service layer signal, the path establishment method also includes steps S610 to S630.

[0085] Step S610: When the first path configuration response message indicates that the path configuration has failed and the cause of the path configuration failure is a time slot conflict, a new outgoing time slot is determined according to the bandwidth indication information.

[0086] Step S620: resend the first path configuration message to the downstream node, wherein the outgoing timeslot port number carried in the resent first path configuration message remains unchanged.

[0087] Step S630: Send a new first service layer signal to the downstream node, wherein the new first service layer signal includes an MSI field, and the MSI field carries the correspondence information between the new outgoing time slot and the outgoing time slot port number.

[0088] It should be noted that after the source node sends the first service layer signal and the first path configuration message to the downstream node, the downstream node of the source node performs corresponding path configuration processing according to the first path configuration message and the first service layer signal, and sends a first path configuration response message according to the path configuration processing result. When the first path configuration response message indicates that the path configuration failed and the cause of the path configuration failure is a time slot conflict, the source node can re-determine a new outgoing time slot based on the bandwidth indication information, and resend the first path configuration message to the downstream node. The outgoing time slot port number carried in the resent first path configuration message remains unchanged, and a new first service layer signal is sent to the downstream node. The MSI field in the new first service layer signal carries the correspondence information between the new outgoing time slot and the outgoing time slot port number.

[0089] In a specific embodiment, the intermediate node acts as a downstream node of the source node, receives the first path configuration message and the first service layer signal sent by the upstream node, and determines the input time slot corresponding to the input time slot port number of the client layer signal based on the MSI subfield containing the input time slot port number in the MSI field of the first service layer signal. The intermediate node then determines whether the input time slot port number and the input time slot are available.

[0090] If the intermediate node determines that the incoming time slot is unavailable, it sends a first path configuration response message to the upstream node, indicating that the path configuration failed and that the cause of the path configuration failure is a time slot conflict. Alternatively, if the intermediate node confirms that both the incoming time slot port number and the incoming time slot are available, it determines the outgoing time slot and outgoing time slot port number corresponding to the client layer signal of the intermediate node. Further, if the intermediate node confirms that the intermediate node does not have outgoing time slot resources that can satisfy the client layer signal, it sends a first path configuration response message to the upstream node, indicating that the path configuration failed and that the cause of the path configuration failure is a time slot conflict.

[0091] After the source node receives the first path configuration response message indicating that the path configuration failed and the reason for the path configuration failure is a time slot conflict, the source node resends the first path configuration message to the downstream node and sends a new first service layer signal to the downstream node, wherein the outgoing time slot port number carried by the resent first path configuration message remains unchanged, and the new first service layer signal includes an MSI field, and the MSI field carries the correspondence information between the new outgoing time slot and the outgoing time slot port number.

[0092] An embodiment of the present application also proposes a path establishment method, which is applied to an intermediate node. Please refer to Figure 11. Figure 11 shows a path establishment method provided by an embodiment of the present application. As shown in Figure 11, the path establishment method includes but is not limited to steps S710 to S770.

[0093] Step S710: Receive a first path configuration message sent by an upstream node, wherein the first path configuration message carries an inbound timeslot port number of a client layer signal of a service path to be established.

[0094] Step S720: Receive a first service layer signal sent by an upstream node, wherein the first service layer signal includes a multiplexing structure indication MSI field.

[0095] Step S730: Determine the incoming time slot corresponding to the incoming time slot port number of the client layer signal according to the MSI subfield containing the incoming time slot port number in the MSI field.

[0096] Step S740: When it is confirmed that the input timeslot port number and the input timeslot are both available, the output timeslot and the output timeslot port number of the node corresponding to the client layer signal are determined.

[0097] Step S750: Send a second service layer signal to the downstream node, wherein the second service layer signal includes an MSI field, and the MSI field carries correspondence information between an outgoing time slot and an outgoing time slot port number.

[0098] Step S760: Send a second path configuration message to the downstream node, wherein the second path configuration message carries the timeslot port number.

[0099] Step S770: Receive a second path configuration response message sent by the downstream node according to the second path configuration message and the second service layer signal.

[0100] It can be understood that after the intermediate node receives the first path configuration message and the first service layer signal sent by the upstream node, it first determines the inbound time slot corresponding to the inbound time slot port number of the client layer signal based on the MSI subfield containing the inbound time slot port number in the MSI field of the first service layer signal. Then, the intermediate node determines whether the inbound time slot port number and the inbound time slot of the client layer signal are occupied. After confirming that the inbound time slot port number and the inbound time slot are both available, the intermediate node then determines the outbound time slot and outbound time slot port number of the client layer signal at the outbound port of the local node, that is, parses the outbound port of the local node and its time slot port number from the second path configuration message, and determines the available idle time slot at the downstream outbound port to allocate a specific outbound time slot, sends a second service layer signal to the downstream node, the MSI field of the second service layer signal carries the correspondence between the outbound time slot and the outbound time slot port number, and sends a second path configuration message to the downstream node, wherein the second path configuration message carries the outbound time slot port number. The intermediate node receives the second path configuration response message sent by the downstream node based on the second path configuration message and the second service layer signal.

[0101] In steps S710 and S720, the intermediate node receives the second service layer signal and the second path configuration message sent by the upstream node sequentially. Therefore, after receiving the second path configuration message, the intermediate node parses the upstream port TPN based on the routing list information in the second path configuration message, and searches the upstream ODU for the MSI overhead based on the TPN value. If the MSI overhead is found, it indicates that the path configuration message and the MSI overhead of the ingress port ODU have been collected. After monitoring the physical frame structure at the upstream ODU port, the intermediate node determines the correspondence between the TPN and the time slot based on the occupied bit information in the MSI overhead, searches the upstream path configuration message for the TPN value that is not set to cross, and confirms that the upstream path configuration message has been received, indicating that the path configuration message and the MSI overhead of the ingress port ODU have been collected.

[0102] In steps S730 and S740, after the intermediate node collects the MSI overhead and the second path configuration message of the second service layer signal, the intermediate node determines the inbound time slot corresponding to the inbound time slot port number of the client layer signal based on the MSI subfield containing the inbound time slot port number in the MSI field. That is, the correspondence information between the inbound time slot and the inbound time slot port number in the MSI overhead is used as a time slot mapping table of the inbound time slot port number on the upstream port. The intermediate node then determines whether the inbound time slot is available. If available, it indicates that the inbound time slot has been occupied by the current connection. If it is found that the inbound time slot corresponding to the port has been occupied by another connection, a rollback is performed, and the intermediate node sends a path configuration response message to the upstream node indicating that the path configuration has failed. After receiving the path configuration response message indicating that the path configuration has failed, the upstream node can reallocate the time slot and resend a new path configuration message.

[0103] It should be noted that after receiving the path configuration message, the intermediate node can directly forward the path configuration message to the downstream node without waiting for the path configuration message and the MSI overhead in the service layer signal to be collected.

[0104] It should also be noted that the above embodiment describes a path establishment method applied to an intermediate node. For its specific implementation, please refer to the relevant description of the path establishment method applied to a source node, which will not be repeated here.

[0105] In some embodiments, after receiving the first path configuration message sent by the upstream node, the path establishment method further includes: when confirming that the incoming timeslot port number is unavailable, sending a first path configuration response message to the upstream node indicating that the path configuration failed.

[0106] It should be understood that after receiving the first path configuration message sent by the upstream node, the intermediate node parses the first path configuration message to obtain the inbound time slot port number of the client layer signal of the service path to be established. The intermediate node then determines whether the inbound time slot port number is already occupied at the inbound port of the intermediate node. If it is determined that the inbound time slot port number is already occupied, the intermediate node sends a first path configuration response message to the upstream node indicating a path configuration failure. After receiving the first path configuration response message indicating a path configuration failure, the upstream node determines a new first path configuration message and a new first service layer signal for the outbound time slot port number of the client layer signal request message based on the new time slot port number. The upstream node then sends the new first path configuration message and the new first service layer signal to the intermediate node.

[0107] In some embodiments, after determining the input time slot corresponding to the input time slot port number of the client layer signal, the path establishment method further includes: if it is confirmed that the input time slot is unavailable, sending a first path configuration response message to the upstream node indicating that the path configuration failed.

[0108] It should be understood that after the intermediate node determines the inbound time slot corresponding to the inbound time slot port number of the client layer signal, the intermediate node determines whether the inbound time slot is available at the inbound port of the intermediate node. If the inbound time slot is determined to be unavailable, the intermediate node sends a first path configuration response message to the upstream node indicating a path configuration failure. After receiving the first path configuration response message indicating a path configuration failure, the upstream node re-determines a new outbound time slot based on the bandwidth indication information, resends the first path configuration message to the downstream node, and carries the same outbound time slot port number. Furthermore, the upstream node sends a new first service layer signal to the downstream node. The new service layer signal includes an MSI field that carries information about the correspondence between the new outbound time slot and the outbound time slot port number.

[0109] In some embodiments, after determining that the client layer signal corresponds to the outgoing time slot and outgoing time slot port number of the current node, the method further includes at least one of the following: when it is confirmed that the current node does not have outgoing time slot resources that can meet the client layer signal, sending a first path configuration response message to the upstream node indicating that the path configuration has failed; or, when it is confirmed that the outgoing time slot port number is unavailable, sending a first path configuration response message to the upstream node indicating that the path configuration has failed.

[0110] It should be understood that after the intermediate node determines that the client layer signal corresponds to the outgoing time slot and the outgoing time slot port number of the current node, the intermediate node determines whether the outgoing time slot and the outgoing time slot port number are available. If it is confirmed that the current node does not have outgoing time slot resources that can meet the client layer signal, the intermediate node sends a first path configuration response message to the upstream node indicating that the path configuration has failed, or, if it is confirmed that the outgoing time slot port number is unavailable, the intermediate node sends a first path configuration response message to the upstream node indicating that the path configuration has failed.

[0111] In some embodiments, after determining the outgoing time slot and outgoing time slot port number of the client layer signal corresponding to the local node, the method further includes: determining a cross-configuration result of the client layer signal according to the incoming time slot and outgoing time slot corresponding to the client layer signal.

[0112] It can be understood that after the intermediate node determines the outgoing time slot and outgoing time slot port number corresponding to the client layer signal of the node, the intermediate node performs a mapping configuration of the incoming ODU signal to the outgoing ODU signal according to the incoming time slot and outgoing time slot corresponding to the client layer signal, and determines the cross-configuration result of the client layer signal.

[0113] It should be noted that the intermediate node can perform cross-configuration before sending the second service layer signal to the downstream node, or can perform cross-configuration after receiving the second path configuration response message sent by the downstream node. That is to say, for each node on the service path, its time slot allocation and cross-configuration can be completed one by one, or the time slot allocation can be completed hop by hop, and then the cross-configuration can be completed hop by hop. The cross-configuration can be achieved in the process of each node sending a path configuration response message for reverse confirmation.

[0114] In some embodiments, after receiving a second path configuration response message sent by the downstream node based on the second path configuration message and the second service layer signal, the method further includes one of the following: when the second path configuration response message indicates that the path configuration is successful and the client layer signal cross-configuration of the local node is successful, sending a first path configuration response message indicating that the path configuration is successful to the upstream node; or, when the second path configuration response message indicates that the path configuration fails, sending a first path configuration response message indicating that the path configuration fails to the upstream node.

[0115] It should be understood that the intermediate node receives the second path configuration response message sent by the downstream node based on the second path configuration message and the second service layer signal. When the second path configuration response message indicates that the path configuration is successful, it indicates that all downstream nodes of the current node have successfully performed path configuration. If the current node successfully cross-configures the client layer signal, the intermediate node sends a first path configuration response message indicating that the path configuration is successful to the upstream node. If the current node fails to successfully cross-configure the client layer signal, the intermediate node sends a first path configuration response message indicating that the path configuration fails to the upstream node. When the second path configuration response message indicates that the path configuration fails, it indicates that the path configuration of the upstream downstream node of the current node fails, and the intermediate node sends the first path configuration response message indicating that the path configuration fails to the upstream node.

[0116] In some embodiments, the first path configuration message and / or the second path configuration message also carries at least one of the following: service identifier, routing list information, bandwidth indication information, time slot port number corresponding to the link through which the service path passes, source access port information, and sink access port information.

[0117] It should be noted that, for the description of the first path configuration message and / or the second path configuration message, reference may be made to the relevant description of the path establishment method applied to the source node, which is not repeated here.

[0118] An embodiment of the present application also proposes a path establishment method, which is applied to a destination node. Please refer to Figure 12. Figure 12 shows a path establishment method provided by an embodiment of the present application. As shown in Figure 12, the path establishment method includes but is not limited to steps S810 to S850.

[0119] Step S810: Receive a path configuration message sent by an upstream node, wherein the path configuration message carries the inbound timeslot port number of the client layer signal of the service path to be established.

[0120] Step S820: Receive a service layer signal sent by an upstream node, wherein the service layer signal includes a multiplexing structure indication MSI field.

[0121] Step S830: Determine the incoming time slot corresponding to the incoming time slot port number of the client layer signal according to the MSI subfield containing the incoming time slot port number in the MSI field.

[0122] Step S840: Determine the path configuration result according to the input time slot port number and the input time slot.

[0123] Step S850: Send a path configuration response message to the upstream node according to the path configuration result.

[0124] It should be understood that the destination node receives the path configuration message and service layer signal sent by the upstream node, wherein the path configuration message carries the input time slot port number of the client layer signal of the service path to be established, and the service layer signal includes the multiplexing structure indication MSI field. Then, the destination node determines the input time slot corresponding to the input time slot port number of the client layer signal based on the MSI subfield containing the input time slot port number in the MSI field, and then determines the path configuration result based on the input time slot port number and whether the input time slot is available. Based on the path configuration result, a path configuration response message is sent to the upstream node, and it is confirmed hop by hop from the destination node to the source node whether the service path is successfully configured.

[0125] It should be understood that, as shown in FIG3 , the MSI encoding format, when using 1.25G time slot granularity mapping, taking the mapping of the low-order ODUflex (4 time slots) to the high-order ODU4 (80 time slots) link as an example, the Bit Map (time slot mapping table) is 80 bits. Assuming that time slots 1 and 7 are allocated to low-order services and the allocated time slot port number TPN is 2, the fields corresponding to time slots 1 and 7 in the MSI field of the high-order OPU4 overhead need to be set to 2. As shown in FIG3 , the corresponding PSI field Tributary Port# corresponding to TS1 and 7 is set to 2. That is, the MSI subfield containing the time slot port number in the MSI field can be the field Tributary Port#.

[0126] It should be noted that the above embodiment describes a path establishment method applied to a destination node. For its specific implementation, reference may be made to the relevant description of the path establishment method applied to an intermediate node, which will not be described in detail here.

[0127] In some embodiments, determining a path configuration result based on an input time slot port number and an input time slot includes one of the following: when it is confirmed that both the input time slot port number and the input time slot are available, cross-mapping configuration is performed on the client layer signal according to the input time slot, and when the cross-configuration is successful, determining that the path configuration result is a successful path configuration; or, when it is confirmed that both the input time slot port number and the input time slot are available, cross-mapping configuration is performed on the client layer signal according to the input time slot, and when the cross-configuration fails, determining that the path configuration result is a path configuration failure; or, when it is confirmed that either the input time slot port number or the input time slot is unavailable, determining that the path configuration result is a path configuration failure.

[0128] It is understandable that the sink node parses the path configuration message to obtain the inbound time slot port number of the client layer signal of the service path to be established, and obtains the inbound time slot corresponding to the inbound time slot port number of the client layer signal from the MSI field. The sink node then determines whether the inbound time slot port number and inbound time slot are occupied at the inbound port of the node, and determines the path configuration result based on whether the node successfully performs cross-configuration. Specifically, if the sink node successfully performs cross-configuration of the client layer signal upon confirming that both the inbound time slot port number and the inbound time slot are available, the path configuration result is determined to be a successful path configuration, and the sink node sends a path configuration response message to the upstream node indicating a path configuration failure. If either the inbound time slot port number or the inbound time slot is confirmed to be unavailable, the path configuration result is directly determined to be a failed path configuration.

[0129] In some embodiments, sending a path configuration reply message to an upstream node based on a path configuration result includes: when the path configuration result is a path configuration success, sending a path configuration reply message to the upstream node indicating that the path configuration is successful; or, when the path configuration result is a path configuration failure, sending a path configuration reply message to the upstream node indicating that the path configuration has failed.

[0130] It should be understood that when the path configuration result indicates that the path configuration is successful, the sink node sends a path configuration reply message to the upstream node indicating that the path configuration is successful. After receiving the path configuration reply message indicating that the path configuration is successful, if the client layer signal cross-configuration on the local node is successful, the upstream node sends a path configuration reply message to the upstream node indicating that the path configuration is successful. If the client layer signal cross-configuration on the local node fails, the upstream node sends a path configuration reply message to the upstream node indicating that the path configuration fails.

[0131] It should be understood that when the path configuration result indicates a path configuration failure, the sink node sends a path configuration reply message to the upstream node, indicating the path configuration failure. After receiving the path configuration reply message indicating a successful path configuration, the upstream node directly sends a path configuration reply message to its upstream node, indicating a path configuration failure, and so on, to achieve reverse confirmation of the path configuration.

[0132] In some embodiments, the path configuration message further carries at least one of the following: service identification, routing list information, bandwidth indication information, time slot port number corresponding to the link through which the service path passes, source access port information, and sink access port information.

[0133] It should be noted that, for the description of the path configuration message, reference may be made to the relevant description of the path establishment method applied to the source node, which will not be elaborated here.

[0134] The following describes the path establishment method provided in the embodiments of the present application through specific examples.

[0135] Example 1

[0136] In the distributed signaling connection issuance scenario under fine grain OTN (fgOTN), the fgODUflex is mapped to the service layer OPU, and the timeslot mapping table, i.e., the correspondence between timeslots and timeslot port numbers, is transmitted using the MSI field in the OPU overhead. Simultaneously, the signaling channel is used to transmit path configuration messages, i.e., path configuration messages, to coordinate and complete the connection issuance. Referring to FIG13 , FIG13 illustrates a path establishment method provided by an embodiment of the present application. As shown in FIG13 , the path establishment method includes the following steps.

[0137] Step 1: The controller sends a path configuration message to the source node. The path configuration message carries at least one of the following: service identifier, routing list information, bandwidth indication information, time slot port number TPN corresponding to the link through which the service path passes, source access port information, and sink access port information. Taking Figure 13 as an example, the routing information list is ports A1, B1, B2, and C1. The TPN used for the link from port A1 to port B1 is 2, and the TPN used for the link from port B2 to port C1 is 4. The bandwidth is 20 Mb / s, requiring two fgODUflex time slots. The source access port and sink access port are A0 and C0 respectively, and the access information is an Ethernet signal.

[0138] In step 2, the source node determines the egress port from this node to the downstream node based on the routing list information. If available idle timeslots are identified based on the bandwidth indication information, the source node allocates a specific timeslot and sets the TPN value corresponding to the egress port in the MSI field of the corresponding ODU overhead. The source node then transmits the ODU frame via the physical channel and sends the path configuration message to the downstream node via the signaling channel. For example, in Figure 13, if the source node allocates timeslots 3 and 5 on port A1, the corresponding timeslot in the MSI field is set to 2 (TPN value).

[0139] The source node can perform the cross-configuration of fgO DUflex from the client layer input port to the output port after completing the downstream output port time slot allocation in this step. The source node can also perform the cross-configuration of fgODUflex from the client layer input port to the output port after receiving the response signaling message indicating the success of the downstream node cross-configuration, such as the cross-configuration of two fgODU time slots from port A0 to port A1 shown in Figure 13.

[0140] In step 3, the path configuration message of the signaling channel and the MSI overhead of the physical channel are received and parsed by the downstream node in a certain order.

[0141] When the signaling channel receives the path configuration message, it parses the TPN value of the upstream port based on the ingress port of the local node in the routing information. It then searches for the MSI overhead in the upstream ODU based on the TPN value. If the MSI overhead is found, it indicates that the path configuration message and the MSI overhead of the ingress port ODU have been collected.

[0142] When the physical channel detects the physical frame structure at the upstream ODU port, it determines the correspondence between the TPN and the time slot based on the occupied bit information in the MSI overhead. It searches for the upstream path configuration message based on the TPN value that is not set to cross. If it is found, it means that the path configuration message and the MSI overhead of the ingress port ODU have been collected.

[0143] After collecting the path configuration message and the MSI overhead of the ingress port ODU, the node uses the MSI to indicate the relevant time slot as the time slot mapping table of the TPN on the upstream port and determines whether the time slot is available. If the time slot is available, it is marked as occupied by this connection. If it is found that the corresponding time slot of the port is occupied by other connections, a rollback is performed. The upstream can respond with a failure message. After receiving it, the upstream reallocates the time slot and resends the path configuration message to the downstream.

[0144] In step 4, after collecting the path configuration message and the MSI overhead of the B1 port ODU, the intermediate node parses the downstream egress port and the corresponding TPN value. If an available idle timeslot is confirmed at the port, it allocates a specific timeslot and sets the TPN value corresponding to the port in the MSI field of the corresponding ODU overhead. The ODU frame is then transmitted to the downstream node via the physical channel, and the path configuration message is also sent to the downstream node via the signaling channel. For example, in Figure 13, if the intermediate node allocates timeslots 6 and 8 on port B2 (TPN5), the corresponding positions in the MSI field corresponding to timeslots 6 and 8 are filled with 4 (TPN value).

[0145] The intermediate node performs cross-configuration based on the allocated downstream ODU time slots and upstream ODU time slots, as shown in Figure 13 for the cross-configuration of two fgODU time slots on ports B1 to B2. If no connection is found, the node continues to wait. If no connection is received after a period of time, the connection establishment fails, and the node responds to the upstream node with a path configuration response message indicating that the path configuration failed, entering the rollback process.

[0146] In step 5, after receiving the Path Configuration message from the upstream signaling channel, the sink node retrieves the MSI field in the OPU overhead transmitted by the upstream physical channel based on the local ingress port in the routing information. It then matches the TPN value to confirm the timeslot position allocated by the upstream node. The sink node determines whether the timeslot is available. If so, it indicates that the timeslot is occupied by the current connection. If the timeslot corresponding to the port is already occupied by another connection, the sink node rolls back the connection. This can be done by sending a failure message to the upstream node. Upon receiving the message, the upstream node reallocates the timeslot and resends the Path Configuration message to the downstream node.

[0147] The sink node determines the client port and access information based on the path configuration message and completes the cross-configuration of the fg ODUflex from the upstream ingress port to the client egress port, such as the cross-configuration of two fgODU timeslots on ports C1 to C0 as shown in FIG13 .

[0148] Step 6: After the destination node completes the crossover, it transmits the crossover result as a path configuration response message back to the intermediate node through the signaling channel. If the crossover fails, the node can clear the crossover information and release the time slot occupancy information.

[0149] In step 7, after receiving the downstream path configuration response message, the intermediate node combines the cross-connection result of the local node and transmits it hop by hop back to the source node. If the cross-connection fails, the local node can clear the cross-connection information and release the time slot occupancy information.

[0150] In step 8, after receiving the downstream path configuration response message, the source node combines the cross-connection result of the local node to determine whether the connection is successfully established. If the cross-connection fails, the local node can clear the cross-connection information and release the time slot occupancy information.

[0151] Example 2

[0152] When multiple connections are allocated simultaneously on a port, they are controlled according to a first-come, first-served allocation principle. As shown in Figure 14, two low-order ODU connections are established simultaneously from nodes A and C. At node B, Path Configuration Message 1 arrives first. After collecting the Path Configuration Message and the MSI overhead of the high-order ODU on port B1, Node B allocates a high-order time slot on port B2, assuming it is time slots 2 and 3 with a TPN of 5. Path Configuration Message 2 arrives later at node B. After collecting the MSI overhead of the Path Configuration Message 2 and the high-order ODU on port B2, Node B performs a verification. The verification fails if the TPN or time slot used by the inbound port is already occupied by another connection, or if the TPN of the outbound port is already occupied by another connection. Figure 14 shows that time slot 3 allocated by Path Configuration Message 2 on port C1 is already used by Path Configuration Message 1. Therefore, the verification fails and a Connection Issuance Response Failure message is sent to node C, indicating that the failure is due to a time slot conflict.

[0153] Node C can reallocate the time slot or TPN according to the reason for the connection provisioning failure, and resend the path configuration message and the MSI overhead of the new high-order ODU to reestablish the connection.

[0154] Please refer to Figure 15. An embodiment of the present application also provides an electronic device, which includes but is not limited to: at least one processor 5001; at least one memory 5002 for storing at least one program; when the at least one program is executed by at least one processor 5001, the path establishment method applied to the user terminal as described in any of the above embodiments is executed; or, the path establishment method applied to the network side node as described in any of the above embodiments is executed.

[0155] It should be understood that the processor 5001 and the memory 5002 may be connected via a bus or other means.

[0156] It should be understood that the processor 5001 can be a central processing unit (CPU). The processor can also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. Alternatively, the processor 5001 uses one or more integrated circuits to execute relevant programs to implement the technical solutions provided in the embodiments of the present application.

[0157] The memory 5002, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer executable programs, such as the path establishment method performed by the electronic device side as described in any embodiment of the present application. The processor 5001 executes the non-transitory software program and instructions stored in the memory 5002 to implement the path establishment method applied to the source node as described in any of the above embodiments, or implements the path establishment method applied to the intermediate node as described in any of the above embodiments, or implements the path establishment method applied to the destination node as described in any of the above embodiments.

[0158] Memory 5002 may include a program storage area and a data storage area. The program storage area may store an operating system and at least one application required for a function; the data storage area may store data for executing the path establishment method described above. Furthermore, memory 5002 may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0159] In some embodiments, the memory 5002 may optionally include a memory remote from the processor 5001, and the remote memory may be connected to the processor 5001 via a network. Examples of the aforementioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0160] The non-transient software programs and instructions required to implement the above-mentioned path establishment method are stored in the memory 5002. When executed by one or more processors 5001, the path establishment method applied to the source node as described in any of the above embodiments is executed, or the path establishment method applied to the intermediate node as described in any of the above embodiments is executed, or the path establishment method applied to the destination node as described in any of the above embodiments is executed.

[0161] An embodiment of the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the path establishment method applied to the source node as described in any of the above embodiments, or implements the path establishment method applied to the intermediate node as described in any of the above embodiments, or implements the path establishment method applied to the destination node as described in any of the above embodiments.

[0162] The computer storage medium of the embodiment of the present application can adopt any combination of one or more computer-readable media.Computer-readable media can be computer-readable signal media or computer-readable storage media.Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or components, or any combination thereof.More specific examples (non-exhaustive) of computer-readable storage media include: electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROMs), optical storage devices, magnetic storage devices, or any suitable combination thereof.In this document, computer-readable storage media can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it.

[0163] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0164] Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0165] The computer program code for performing the operations of the present application can be written in one or more programming languages, or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (such as through the Internet using an Internet service provider).

[0166] An embodiment of the present application further provides a computer program product, which stores program instructions. When the program instructions are executed on a computer device, the computer device implements the path establishment method applied to the source node as described in any of the above embodiments, or implements the path establishment method applied to the intermediate node as described in any of the above embodiments, or implements the path establishment method applied to the destination node as described in any of the above embodiments.

[0167] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above implementation mode. Technical personnel familiar with the field can also make various equivalent modifications or substitutions without violating the essential sharing conditions of the present application. These equivalent modifications or substitutions are all included in the scope defined by the present application.

Claims

1. A path establishment method, applied to a source node, comprising: Obtain bandwidth indication information of a client layer signal of a service path to be established and an outgoing time slot port number corresponding to the node; Determine a time slot according to the bandwidth indication information; Sending a first service layer signal to a downstream node, wherein the first service layer signal includes a multiplexing structure indication MSI field, and the MSI field carries the correspondence information between the outgoing time slot and the outgoing time slot port number; Sending a first path configuration message to the downstream node, wherein the first path configuration message carries the outgoing time slot port number corresponding to the node; Receive a first path configuration response message sent by the downstream node based on the first path configuration message and the first service layer signal.

2. The method according to claim 1, wherein: The determining the time slot according to the bandwidth indication information includes: Determine the number of time slots that the client layer signal needs to occupy according to the bandwidth indication information; The outgoing time slot corresponding to the number of time slots is determined from the idle time slot resources of the node.

3. The method according to claim 1, wherein: The first path configuration message also carries at least one of the following: a service identifier, routing list information, bandwidth indication information, a timeslot port number corresponding to a link through which the service path passes, source access port information, and sink access port information.

4. The method according to claim 1, characterized in that: Before obtaining the bandwidth indication information of the client layer signal of the service path to be established and the outgoing time slot port number corresponding to the current node, the method further includes: Receiving a service path request message sent by a controller, wherein the service path request message indicates establishing a service path for carrying the client layer signal; The step of obtaining bandwidth indication information of a client layer signal of a service path to be established and an outgoing time slot port number corresponding to the node includes: The bandwidth indication information of the client layer signal and the outgoing time slot port number corresponding to the current node are confirmed according to the service path request message.

5. The method according to claim 4, wherein: The service path request message carries at least one of the following: service identification, routing list information, bandwidth indication information, time slot port number corresponding to the link through which the service path passes, source access port information, and sink access port information.

6. The method according to claim 1, wherein: After receiving a first path configuration response message sent by the downstream node according to the first path configuration message and the first service layer signal, the method further includes: When the first path configuration response message indicates that the path configuration is successful, the client layer signal is carried in the third service layer signal through the outgoing time slot, and the third service layer signal is sent to the downstream node.

7. The method according to claim 6, wherein: After receiving a first path configuration response message sent by the downstream node according to the first path configuration message and the first service layer signal, the method further includes: When the first path configuration response message indicates that the path configuration fails and the cause of the path configuration failure is a timeslot port number conflict, requesting a new timeslot port number for the client layer signal for the link where the timeslot port number conflict occurs; Determine a new first path configuration message and a new first service layer signal according to the new timeslot port number; Sending the new first path configuration message to the downstream node; Send the new first service layer signal to the downstream node.

8. The method according to claim 6, wherein: After receiving a first path configuration response message sent by the downstream node according to the first path configuration message and the first service layer signal, the method further includes: When the first path configuration response message indicates that the path configuration fails and the cause of the path configuration failure is a time slot conflict, determining a new outgoing time slot according to the bandwidth indication information; Resending the first path configuration message to the downstream node, wherein the outgoing time slot port number carried in the resent first path configuration message remains unchanged; A new first service layer signal is sent to the downstream node, wherein the new first service layer signal includes the MSI field, and the MSI field carries the correspondence information between the new outgoing time slot and the outgoing time slot port number.

9. A path establishment method, applied to an intermediate node, the method comprising: Receiving a first path configuration message sent by an upstream node, wherein the first path configuration message carries an inbound timeslot port number of a client layer signal of a service path to be established; Receiving a first service layer signal sent by the upstream node, wherein the first service layer signal includes a multiplexing structure indication MSI field; Determining an input time slot corresponding to the input time slot port number of the client layer signal according to the MSI subfield containing the input time slot port number in the MSI field; When confirming that the input time slot port number and the input time slot are both available, determining the output time slot and the output time slot port number of the node corresponding to the client layer signal; Sending a second service layer signal to a downstream node, wherein the second service layer signal includes the MSI field, and the MSI field carries the correspondence information between the outgoing time slot and the outgoing time slot port number; Sending a second path configuration message to the downstream node, wherein the second path configuration message carries the outgoing time slot port number; Receive a second path configuration response message sent by the downstream node based on the second path configuration message and the second service layer signal.

10. The method according to claim 9, wherein: After receiving the first path configuration message sent by the upstream node, the method further includes: When it is confirmed that the inbound time slot port number is unavailable, a first path configuration response message indicating a path configuration failure is sent to the upstream node.

11. The method according to claim 9, wherein: After determining the input time slot corresponding to the input time slot port number of the client layer signal, the method further comprises: When it is confirmed that the input time slot is unavailable, a first path configuration response message indicating a path configuration failure is sent to the upstream node.

12. The method according to claim 9, wherein: After determining the outgoing time slot and the outgoing time slot port number of the node corresponding to the client layer signal, the method further includes at least one of the following: When confirming that the local node does not have an outgoing time slot resource that can satisfy the client layer signal, sending a first path configuration response message indicating a path configuration failure to the upstream node; or, When it is confirmed that the outgoing time slot port number is unavailable, a first path configuration response message indicating a path configuration failure is sent to the upstream node.

13. The method according to claim 9, wherein: After determining the outgoing time slot and the outgoing time slot port number of the node corresponding to the client layer signal, the method further includes: The cross-configuration result of the client layer signal is determined according to the input time slot and the output time slot corresponding to the client layer signal.

14. The method according to claim 9, wherein: After receiving the second path configuration response message sent by the downstream node according to the second path configuration message and the second service layer signal, the method further includes one of the following: When the second path configuration response message indicates that the path configuration is successful and the client layer signal is successfully cross-configured at the local node, sending a first path configuration response message indicating that the path configuration is successful to the upstream node; or, In a case where the second path configuration response message indicates that the path configuration fails, a first path configuration response message indicating that the path configuration fails is sent to the upstream node.

15. The method according to claim 9, wherein: The first path configuration message and / or the second path configuration message also carries at least one of the following: service identification, routing list information, bandwidth indication information, time slot port number corresponding to the link through which the service path passes, source access port information, and sink access port information.

16. A path establishment method, applied to a sink node, the method comprising: receiving a path configuration message sent by an upstream node, wherein the path configuration message carries an inbound timeslot port number of a client layer signal of a service path to be established; Receiving a service layer signal sent by the upstream node, wherein the service layer signal includes a multiplexing structure indication MSI field; Determining an input time slot corresponding to the input time slot port number of the client layer signal according to the MSI subfield containing the input time slot port number in the MSI field; Determine a path configuration result according to the input time slot port number and the input time slot; Send a path configuration response message to the upstream node according to the path configuration result.

17. The method according to claim 16, wherein: The determining of the path configuration result according to the input time slot port number and the input time slot comprises one of the following: When it is confirmed that the input time slot port number and the input time slot are both available, cross-mapping configuration is performed on the client layer signal according to the input time slot, and when the cross-mapping configuration is successful, the path configuration result is determined to be a path configuration success; or, When confirming that the input time slot port number and the input time slot are both available, cross-mapping configuration is performed on the client layer signal according to the input time slot, and when the cross-mapping configuration fails, determining that the path configuration result is a path configuration failure; or, When it is confirmed that any one of the input time slot port number and the input time slot is unavailable, it is determined that the path configuration result is a path configuration failure.

18. The method according to claim 17, wherein: The sending a path configuration response message to the upstream node according to the path configuration result includes: When the path configuration result is that the path configuration is successful, sending a path configuration response message indicating that the path configuration is successful to the upstream node; or, When the path configuration result is a path configuration failure, a path configuration response message indicating the path configuration failure is sent to the upstream node.

19. The method according to claim 16, wherein: The path configuration message also carries at least one of the following: service identification, routing list information, bandwidth indication information, time slot port number corresponding to the link through which the service path passes, source access port information, and sink access port information.

20. A network node, comprising: one or more processors; A memory having one or more programs stored thereon, when the one or more programs are executed by the one or more processors, the one or more processors implement: The path establishment method according to any one of claims 1 to 8; or The path establishment method according to any one of claims 9 to 15; or, A path establishment method as described in any one of claims 16 to 20.

21. A computer-readable storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the program implements: The path establishment method according to any one of claims 1 to 8; or The path establishment method according to any one of claims 9 to 15; or, A path establishment method as described in any one of claims 16 to 20.

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