WO2021022944A1 - Route calculation method involving stack depth constraint, and device - Google Patents

Route calculation method involving stack depth constraint, and device Download PDF

Info

Publication number
WO2021022944A1
WO2021022944A1 PCT/CN2020/099017 CN2020099017W WO2021022944A1 WO 2021022944 A1 WO2021022944 A1 WO 2021022944A1 CN 2020099017 W CN2020099017 W CN 2020099017W WO 2021022944 A1 WO2021022944 A1 WO 2021022944A1
Authority
WO
WIPO (PCT)
Prior art keywords
path
stack
calculation
algorithm
stack depth
Prior art date
Application number
PCT/CN2020/099017
Other languages
French (fr)
Chinese (zh)
Inventor
张天祥
陆钱春
李锋
刘万慧
Original Assignee
南京中兴软件有限责任公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 南京中兴软件有限责任公司 filed Critical 南京中兴软件有限责任公司
Publication of WO2021022944A1 publication Critical patent/WO2021022944A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/50—Routing or path finding of packets in data switching networks using label swapping, e.g. multi-protocol label switch [MPLS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/12—Shortest path evaluation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L45/00—Routing or path finding of packets in data switching networks
    • H04L45/34—Source routing

Definitions

  • the embodiments of the present invention relate to the field of communication technology, and in particular to a method and device for path calculation with stack depth constraints.
  • SR Segment Routing
  • MPLS Multi-Protocol Label Switching, Multi-Protocol Label Switching
  • the control plane is implemented based on the IGP routing protocol extension
  • the forwarding layer is implemented based on the MPLS forwarding network
  • the corresponding segment identifier is presented as a label at the forwarding layer.
  • SR-TE SR Traffic Engineering
  • the SDN controller is responsible for calculating the forwarding path of the tunnel and sending the label stack list corresponding to the path to the ingress forwarding device , The forwarding device sequentially performs routing and forwarding according to the label stack list.
  • the technical problem to be solved by the embodiment of the present invention is to solve the optimal path calculation problem with MSD constraints, and to provide a method and device for path calculation with stack depth constraints.
  • the method for calculating a path with a stack depth constraint includes: calculating a first path based on a stack depth constraint value using a first preset algorithm; if the depth of the label stack list corresponding to the first path is less than or If it is equal to the stack depth constraint value, output the first path.
  • the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label list stack depth is less than or equal to the first preset algorithm of the stack depth constraint value.
  • the device for calculating a path with a stack depth constraint includes: a first algorithm module configured to calculate the first path based on the stack depth constraint value and using a first preset algorithm; if the first path corresponds to If the depth of the label stack list is less than or equal to the stack depth constraint value, the first path is output.
  • the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label list stack depth is less than or equal to the first preset algorithm of the stack depth constraint value.
  • the segment routing path label processing device includes: a memory, a processor, and a computer program stored in the memory and capable of running on the processor, the computer program being executed by the processor When implementing the steps of the method described above.
  • the path with the stack depth constraint can be calculated by Bellman algorithm first, and if the first path that meets the stack depth constraint value condition is obtained, then the first path is output;
  • the first path that meets the stack depth constraint value condition is first calculated by the basic algorithm without considering the stack depth constraint value for path calculation, and the calculated label stack list of the second path is compressed to obtain the stack depth constraint value condition Path, which greatly improves the success rate of calculating paths with stack depth constraints.
  • a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, the steps of the path calculation method with stack depth constraint as described above are implemented.
  • the path with the stack depth constraint can be calculated by Bellman algorithm. If the first path that meets the stack depth constraint value condition is obtained, the first path is output; if the stack depth constraint is not obtained For the first path of the value condition, the basic algorithm is used to first calculate the path calculation without considering the stack depth constraint value, and the calculated label stack list of the second path is compressed to obtain the path that meets the stack depth constraint value. It greatly improves the success rate of calculating paths with stack depth constraints.
  • Fig. 1 is a flowchart of a path calculation method with stack depth constraints according to an embodiment of the present invention
  • FIG. 2 is a detailed flowchart of a path calculation method with stack depth constraints according to an embodiment of the present invention
  • FIG. 3 is a schematic structural diagram of a path calculation device with stack depth constraints according to an embodiment of the present invention.
  • FIG. 4 is a schematic structural diagram of a path calculation device with stack depth constraints according to an embodiment of the present invention.
  • Fig. 5 is a network topology structure diagram according to an embodiment of the present invention.
  • the forwarding devices produced by major communication equipment manufacturers are limited in their support for the label stack list stack depth, that is, when the stack depth exceeds MSD (Maximum Stack Depth), routing and forwarding will fail, which greatly affects SR Technology and promotion of SR-TE. Therefore, it is necessary to use the characteristics of the SR technology to design a new label path calculation method according to the interaction characteristics of the forwarding layer and the controller to ensure the optimal path while satisfying the MSD constraints.
  • MSD Maximum Stack Depth
  • the method for path calculation with stack depth constraints includes:
  • S101 Calculate the first path by using the first preset algorithm based on the stack depth constraint value
  • the path calculation method of this application can be used to calculate an optimal path with MSD (Maximum Stack Depth, maximum stack depth), and the MSD in this application can be understood as a stack depth constraint value.
  • MSD Maximum Stack Depth, maximum stack depth
  • the stack depth and the constraint value can be used as calculation conditions and input into the first preset algorithm to calculate the first path.
  • the first path whose label stack list depth is less than or equal to the MSD can be directly settled through the first preset algorithm.
  • the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label stack depth list can be directly calculated to be less than or equal to the first value of the stack depth constraint.
  • Path which greatly improves the success rate of calculating paths with stack depth constraints.
  • the method further includes: S103: when the first preset algorithm cannot output the first path, the second preset algorithm is used to calculate without considering the stack The second path of the deep constraint value is compressed, and the label stack list corresponding to the second path is compressed so that the depth of the compressed label stack list is less than or equal to the stack depth constraint value, and the path corresponding to the compressed label stack list is output.
  • the first path whose label list depth is less than or equal to MSD may not be directly calculated through the first preset algorithm.
  • the second preset algorithm can be used to first calculate the path that does not consider the MSD and obtain the second path, and then the label stack of the second path The list is compressed to obtain a path whose label stack list depth is less than or equal to MSD.
  • compressing the label stack list corresponding to the second path includes: replacing at least part of the link labels in the label list with corresponding node labels to reduce the depth of the label stack list.
  • all link labels in the label list can be replaced with corresponding node labels, or part of the link labels in the label list can be replaced with corresponding node labels. As a result, the depth of the tag list can be reduced.
  • the second path from node 1 to node 4 is: 1->2->5->3->4, the corresponding The label list is ⁇ "1->2", “2->5", “5->3", “3->4" ⁇ , and the stack depth is 4, which does not meet the MSD constraint requirements.
  • the label list of the second path is compressed, and the link label in the label list is replaced with the corresponding node label.
  • the label stack list is ⁇ "5", "4" ⁇ , and the stack depth is 2, which meets the MSD constraint requirements.
  • the explanation is that the complete path of the request is divided into two parts, one part is the shortest path 1->2->5 from the starting node 1 to node 5, and the other part is the shortest path 5->4->3 from node 5 to node 4 .
  • the method may further include:
  • the first path or the second path is calculated.
  • preparing path calculation resources includes:
  • path caching can be performed based on the link weight of the forwarding device level.
  • the forwarding device reports to each IGP of the controller through the protocol.
  • the controller performs path cache calculation for the IGP domain. Therefore, when performing path calculation, the shortest path between two nodes can be directly read from the cache, which improves the efficiency of path calculation.
  • the first preset algorithm is Bellman's algorithm
  • the second preset algorithm is Dijkstra's algorithm or Floyed's algorithm.
  • the Bellman algorithm is used to calculate the optimal path with MSD constraints. As a shortest path algorithm, the Bellman algorithm naturally adapts to the path calculation under the maximum hop number constraint, which is also not available in other path algorithms .
  • the depth of the label stack list calculated by Bellman is equal to the total number of all links in the path. At this time, all the labels in the label stack list are the Adj-SID of the link. When the label list stack depth is less than or equal to MSD, the path calculation is considered successful, the result is returned, and the algorithm ends.
  • S11 The forwarding layer network topology status report.
  • the forwarding layer will have multiple IGP domains. Each IGP domain corresponds to the topology shown in Figure 4. When the device is working, the topology of each IGP domain needs to be changed through the communication protocol. Report to the controller;
  • S12 The controller initializes the bandwidth resource, records the link information initialized by S11 to the bandwidth management, initializes the bandwidth resource information for each link, records the maximum, used, and unused bandwidth resources, and calculates the road time Provide reference for link feasibility judgment;
  • the controller caches the entire network path for each IGP domain. After steps S11 and S12, the controller has a grasp of global network information. For each IGP domain, the controller calculates the shortest distance between all nodes in the domain. Path and store, and this step will be triggered whenever the controller restarts or the topology changes;
  • step S14 Use the Bellman algorithm to calculate the optimal path with the maximum stack depth constraint.
  • the algorithm is called, and the bandwidth management module is used to calculate the path. If the path calculation is successful, proceed directly to step S17 to return the path calculation result; otherwise, proceed to step S15;
  • step S15 This step first uses the common path calculation method to obtain an optimal path that does not meet the MSD constraints. On the basis of the established path, the strict LEA algorithm is used to compress the path; if the compression is successful, go directly to step S17 and return As a result, otherwise go to step S16;
  • step S16 In this step, a common path calculation method is first used to obtain an optimal path that does not satisfy the MSD constraint. On the basis of the established path, the loose LEA algorithm is used to compress the path; then step S17 is entered.
  • the device for path calculation with stack depth constraints includes: a first algorithm module.
  • the first algorithm module is set to calculate the first path by using the first preset algorithm based on the stack depth constraint value. If the depth of the label stack list corresponding to the first path is less than or equal to the stack depth constraint value, the first path is output.
  • the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label list stack depth can be directly calculated to be less than or equal to the first preset algorithm of the stack depth constraint value.
  • the device further includes: a second algorithm module.
  • the second algorithm module may be configured to use the second preset algorithm to calculate the second path without considering the stack depth constraint value when the first calculation module cannot output the first path, and compress the label stack list corresponding to the second path, Make the depth of the compressed label stack list less than or equal to the stack depth constraint value, and output the path corresponding to the compressed label stack list.
  • the first path with the label stack list depth less than or equal to MSD can be directly settled through the first preset algorithm, but it may also be impossible to use the first preset algorithm Directly calculate the first path whose label list depth is less than or equal to MSD.
  • the second preset algorithm can be used to first calculate the path that does not consider MSD and obtain the second path, and then the second path The label stack list of the path is compressed to obtain the path whose label stack list depth is less than or equal to MSD.
  • the second algorithm module when the second algorithm module compresses the label stack list corresponding to the second path, it is specifically set to replace at least part of the link labels in the label list with corresponding node labels to reduce the label stack. List depth.
  • all link labels in the label list can be replaced with corresponding node labels, or part of the link labels in the label list can be replaced with corresponding node labels. As a result, the depth of the tag list can be reduced.
  • the second path from node 1 to node 4 is: 1->2->5->3->4, the corresponding The label list is ⁇ "1->2", “2->5", “5->3", “3->4" ⁇ , and the stack depth is 4, which does not meet the MSD constraint requirements.
  • the label list of the second path is compressed, and the link label in the label list is replaced with the corresponding node label.
  • the label stack list is ⁇ "5", "4" ⁇ , and the stack depth is 2, which meets the MSD constraint requirements.
  • the explanation is that the complete path of the request is divided into two parts, one part is the shortest path 1->2->5 from the starting node 1 to node 5, and the other part is the shortest path 5->4->3 from node 5 to node 4 .
  • the device may further include: a resource preparation module, which is configured to prepare path calculation resources before performing the first path calculation; Computing resources to perform the calculation of the first path or the second path.
  • a resource preparation module which is configured to prepare path calculation resources before performing the first path calculation
  • Computing resources to perform the calculation of the first path or the second path.
  • the resource preparation module may include: a topology loading module and a path caching module
  • the topology loading module can be set to report network topology information to the controller
  • the path cache module may be configured to perform path cache calculation based on network topology information to obtain path calculation resources.
  • path caching can be performed based on the link weight of the forwarding device level.
  • the forwarding device reports to each IGP of the controller through the protocol.
  • the controller performs path cache calculation for the IGP domain. Therefore, when performing path calculation, the shortest path between two nodes can be directly read from the cache, which improves the efficiency of path calculation.
  • the first preset algorithm may be the Bellman algorithm
  • the second preset algorithm may be the Dijkstra algorithm or the Floyed algorithm.
  • the Bellman algorithm is used to calculate the optimal path with MSD constraints. As a shortest path algorithm, the Bellman algorithm naturally adapts to the path calculation under the maximum hop number constraint, which is also not available in other path algorithms .
  • the depth of the label stack list calculated by Bellman is equal to the total number of all links in the path. At this time, all the labels in the label stack list are the Adj-SID of the link. When the label list stack depth is less than or equal to MSD, the path calculation is considered successful, the result is returned, and the algorithm ends.
  • the segment routing path label processing device includes: a memory, a processor, and a computer program stored in the memory and running on the processor.
  • the computer program is executed by the processor to implement the steps of the above method .
  • the path with the stack depth constraint can be calculated by Bellman algorithm first, and if the first path that meets the stack depth constraint value condition is obtained, then the first path is output;
  • the first path that meets the stack depth constraint value condition is first calculated by the basic algorithm without considering the stack depth constraint value for path calculation, and the calculated label stack list of the second path is compressed to obtain the stack depth constraint value condition Path, which greatly improves the success rate of calculating paths with stack depth constraints.
  • a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, the steps of the above-mentioned path calculation method with stack depth constraints are implemented.
  • the path with the stack depth constraint can be calculated by Bellman algorithm. If the first path that meets the stack depth constraint value condition is obtained, the first path is output; if the stack depth constraint is not obtained For the first path of the value condition, the basic algorithm is used to first calculate the path calculation without considering the stack depth constraint value, and the calculated label stack list of the second path is compressed to obtain the path that meets the stack depth constraint value. It greatly improves the success rate of calculating paths with stack depth constraints.
  • Figure 4 shows a network topology with 10 nodes and 13 links. Each link has its corresponding weight. Let the Adj-SID of link A->B be "A->B", Let the Node-SID of node A be "A”. In order to explain the problem simply, the bandwidth resource information of the link is ignored, but the main flow of the algorithm is not affected.
  • the network topology is considered to be a single IGP domain, and a single IGP domain is used here for the presentation process.
  • the controller Through reporting at the forwarding level, the controller obtains a single IGP network topology, and uses the link weight as the criterion to perform global path caching, as shown in the following table (only some results are listed as examples in the table):
  • the Bellman algorithm in step S14 in Figure 2 can be used to obtain the optimal path as 1->2->5->3->4 or 1->6- >8->3->4, the direct calculation is successful, and the result is returned.
  • the label stack list is ⁇ "1->2", “2->5", "5->3", “ 3->4” ⁇ . It is worth noting that at this time, even if the common path calculation algorithm is used, the optimal path that satisfies the MSD constraint can be obtained.
  • the label compression method proposed in the embodiment of the present invention is to solve the situation that the MSD constraint in the project is relatively small. In fact, the MSD in the actual project is not large.
  • the complete path of the request is divided into two parts, one part is the shortest path 1->2->5 from the starting node 1 to node 5, and the other part is the shortest path 5->4->3 from node 5 to node 4 ,
  • This also makes full use of the characteristics of the Segment Routing technology, that is, the Node-SID is used to guide the routing along the shortest path.
  • the complete path at this time can be uniquely represented, and the path is determined as 1->2->5->3->4 when the forwarding device performs routing and forwarding.
  • the embodiment of the present invention integrates three path calculation schemes based on stack depth constraints, which greatly improves the path calculation success rate.
  • the method and device for path calculation with stack depth constraint provided by the embodiments of the present invention have the following beneficial effects: the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition and directly calculated
  • the first path whose label list stack depth is less than or equal to the stack depth constraint value improves the efficiency and success rate of calculating the path with the stack depth constraint value.

Abstract

Embodiments of the present invention provide a route calculation method involving a stack depth constraint and a device. The calculation method comprises: calculating, by using a first pre-determined algorithm, a first route on the basis of a stack depth constraint value; and if a label stack list depth corresponding to the first route is less than or equal to the stack depth constraint value, outputting the first route. The calculation method according to the embodiments of the present invention enables the stack depth constraint value to be input into the first pre-determined algorithm and serve as a calculation constraint condition, and obtains, by means of direct calculation, the first route having a label list stack depth less than or equal to the stack depth constraint value, thereby improving efficiency and a success rate of route calculation involving a stack depth constraint value.

Description

针对具有栈深约束的路径计算方法及装置Method and device for path calculation with stack depth constraint 技术领域Technical field
本发明实施例涉及通信技术领域，尤其是涉及一种针对具有栈深约束的路径计算方法及装置。The embodiments of the present invention relate to the field of communication technology, and in particular to a method and device for path calculation with stack depth constraints.
背景技术Background technique
SR(Segment Routing，分段路由)是一种新型的MPLS(Multi-Protocol Label Switching，多协议标签交换)技术。其中，控制平面基于IGP路由协议扩展实现，转发层面基于MPLS转发网络实现，对应的Segment标识在转发层面呈现为标签。SR-TE(SR Traffic Engineering)是使用SR作为控制信令的一种新型的MPLS隧道技术，SDN控制器负责计算隧道的转发路径，并将与路径对应的标签栈列表下发给入节点转发设备，转发设备依次根据标签栈列表进行路由转发。SR (Segment Routing) is a new type of MPLS (Multi-Protocol Label Switching, Multi-Protocol Label Switching) technology. Among them, the control plane is implemented based on the IGP routing protocol extension, the forwarding layer is implemented based on the MPLS forwarding network, and the corresponding segment identifier is presented as a label at the forwarding layer. SR-TE (SR Traffic Engineering) is a new type of MPLS tunnel technology that uses SR as control signaling. The SDN controller is responsible for calculating the forwarding path of the tunnel and sending the label stack list corresponding to the path to the ingress forwarding device , The forwarding device sequentially performs routing and forwarding according to the label stack list.
当前，各大通信设备厂商生产的转发设备对标签栈列表栈深支持程度受到限制，即当栈深超过MSD(Maximum Stack Depth)时，会导致路由转发失败，这在很大程度上影响了SR技术以及SR-TE的推广。Currently, the forwarding devices produced by major communication equipment manufacturers are limited in their support for the label stack list stack depth, that is, when the stack depth exceeds MSD (Maximum Stack Depth), routing and forwarding will fail, which greatly affects SR Technology and promotion of SR-TE.
针对相关技术中存在的上述问题，目前尚未提出有效的解决方案。In view of the above-mentioned problems existing in related technologies, no effective solutions have been proposed at present.
发明内容Summary of the invention
本发明实施例要解决的技术问题是解决带有MSD约束的最优路径计算问题，提供一种针对具有栈深约束的路径计算方法及装置。The technical problem to be solved by the embodiment of the present invention is to solve the optimal path calculation problem with MSD constraints, and to provide a method and device for path calculation with stack depth constraints.
根据本发明实施例的针对具有栈深约束的路径计算方法，包括：基于栈深约束值，采用第一预设算法计算第一路径；若所述第一路径对应的标签栈列表的深度小于或等于所述栈深约束值，则输出所述第一路径。The method for calculating a path with a stack depth constraint according to an embodiment of the present invention includes: calculating a first path based on a stack depth constraint value using a first preset algorithm; if the depth of the label stack list corresponding to the first path is less than or If it is equal to the stack depth constraint value, output the first path.
根据本发明实施例的针对具有栈深约束的路径计算方法，可以通过将栈深约束值输入第一预设算法，作为计算约束条件，直接计算得到标签列表栈深度小于等于栈深约束值的第一路径，从而极大提高了计算具有栈深 约束值的路径的效率和成功率。According to the method for path calculation with stack depth constraint according to the embodiment of the present invention, the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label list stack depth is less than or equal to the first preset algorithm of the stack depth constraint value. One path, thereby greatly improving the efficiency and success rate of calculating paths with stack depth constraints.
根据本发明实施例的针对具有栈深约束的路径计算装置，包括：第一算法模块，设置为基于栈深约束值，采用第一预设算法计算第一路径；若所述第一路径对应的标签栈列表的深度小于或等于所述栈深约束值，则输出所述第一路径。According to the embodiment of the present invention, the device for calculating a path with a stack depth constraint includes: a first algorithm module configured to calculate the first path based on the stack depth constraint value and using a first preset algorithm; if the first path corresponds to If the depth of the label stack list is less than or equal to the stack depth constraint value, the first path is output.
根据本发明实施例的针对具有栈深约束的路径计算装置，可以通过将栈深约束值输入第一预设算法，作为计算约束条件，直接计算得到标签列表栈深度小于等于栈深约束值的第一路径，从而极大提高了计算具有栈深约束值的路径的效率和成功率。According to the embodiment of the present invention for the path calculation device with stack depth constraint, the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label list stack depth is less than or equal to the first preset algorithm of the stack depth constraint value. One path, thereby greatly improving the efficiency and success rate of calculating paths with stack depth constraints.
根据本发明实施例的分段路由路径标签处理装置，包括：存储器、处理器及存储在所述存储器上并可在所述处理器上运行的计算机程序，所述计算机程序被所述处理器执行时实现如上述所述的方法的步骤。The segment routing path label processing device according to the embodiment of the present invention includes: a memory, a processor, and a computer program stored in the memory and capable of running on the processor, the computer program being executed by the processor When implementing the steps of the method described above.
根据本发明实施例的分段路由路径标签处理装置，首先可以通过Bellman算法计算具有栈深约束的路径，若得到符合栈深约束值条件的第一路径，则输出第一路径；若得不到符合栈深约束值条件的第一路径，则通过基本算法先计算不考虑栈深约束值进行路径计算，并对计算得到的第二路径的标签栈列表进行压缩，得到符合栈深约束值条件的路径，从而极大提高了计算具有栈深约束值的路径成功率。According to the segment routing path label processing device of the embodiment of the present invention, the path with the stack depth constraint can be calculated by Bellman algorithm first, and if the first path that meets the stack depth constraint value condition is obtained, then the first path is output; The first path that meets the stack depth constraint value condition is first calculated by the basic algorithm without considering the stack depth constraint value for path calculation, and the calculated label stack list of the second path is compressed to obtain the stack depth constraint value condition Path, which greatly improves the success rate of calculating paths with stack depth constraints.
根据本发明实施例的计算机存储介质，所述计算机存储介质上存储有计算机程序，所述计算机程序被处理器执行时实现如上述所述的针对具有栈深约束的路径计算方法的步骤。According to the computer storage medium of the embodiment of the present invention, a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, the steps of the path calculation method with stack depth constraint as described above are implemented.
根据本发明实施例的计算机存储介质，首先可以通过Bellman算法计算具有栈深约束的路径，若得到符合栈深约束值条件的第一路径，则输出第一路径；若得不到符合栈深约束值条件的第一路径，则通过基本算法先计算不考虑栈深约束值进行路径计算，并对计算得到的第二路径的标签栈列表进行压缩，得到符合栈深约束值条件的路径，从而极大提高了计算具有栈深约束值的路径成功率。According to the computer storage medium of the embodiment of the present invention, the path with the stack depth constraint can be calculated by Bellman algorithm. If the first path that meets the stack depth constraint value condition is obtained, the first path is output; if the stack depth constraint is not obtained For the first path of the value condition, the basic algorithm is used to first calculate the path calculation without considering the stack depth constraint value, and the calculated label stack list of the second path is compressed to obtain the path that meets the stack depth constraint value. It greatly improves the success rate of calculating paths with stack depth constraints.
附图说明Description of the drawings
图1是根据本发明实施例的针对具有栈深约束的路径计算方法流程图；Fig. 1 is a flowchart of a path calculation method with stack depth constraints according to an embodiment of the present invention;
图2是根据本发明实施例的针对具有栈深约束的路径计算方法的详细流程图；2 is a detailed flowchart of a path calculation method with stack depth constraints according to an embodiment of the present invention;
图3是根据本发明实施例的针对具有栈深约束的路径计算装置的结构示意图；3 is a schematic structural diagram of a path calculation device with stack depth constraints according to an embodiment of the present invention;
图4是根据本发明实施例的针对具有栈深约束的路径计算装置的结构示意图；4 is a schematic structural diagram of a path calculation device with stack depth constraints according to an embodiment of the present invention;
图5是根据本发明实施例的网络拓扑结构图。Fig. 5 is a network topology structure diagram according to an embodiment of the present invention.
具体实施方式detailed description
为更进一步阐述本发明为达成预定目的所采取的技术手段及功效，以下结合附图及较佳实施例，对本发明进行详细说明如后。In order to further explain the technical means and effects of the present invention to achieve the predetermined purpose, the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.
当前，各大通信设备厂商生产的转发设备对标签栈列表栈深支持程度受到限制，即当栈深超过MSD(Maximum Stack Depth)时，会导致路由转发失败，这在很大程度上影响了SR技术以及SR-TE的推广。因此，需要利用SR技术的特点，根据转发层面与控制器的交互特性，设计新的标签路径计算方法，在满足MSD约束的同时保证最优路径。Currently, the forwarding devices produced by major communication equipment manufacturers are limited in their support for the label stack list stack depth, that is, when the stack depth exceeds MSD (Maximum Stack Depth), routing and forwarding will fail, which greatly affects SR Technology and promotion of SR-TE. Therefore, it is necessary to use the characteristics of the SR technology to design a new label path calculation method according to the interaction characteristics of the forwarding layer and the controller to ensure the optimal path while satisfying the MSD constraints.
如图1所示，根据本发明实施例的针对具有栈深约束的路径计算方法，包括：As shown in FIG. 1, the method for path calculation with stack depth constraints according to an embodiment of the present invention includes:
S101：基于栈深约束值，采用第一预设算法计算第一路径；S101: Calculate the first path by using the first preset algorithm based on the stack depth constraint value;
需要说明的是，本申请的路径计算方法可以用于针对具有MSD(Maximum Stack Depth，最大栈深)的最优路径的计算，本申请中的MSD可以理解为栈深约束值。在进行路径计算时，可以将栈深与约束值作为计 算条件输入第一预设算法，计算出第一路径。It should be noted that the path calculation method of this application can be used to calculate an optimal path with MSD (Maximum Stack Depth, maximum stack depth), and the MSD in this application can be understood as a stack depth constraint value. When calculating the path, the stack depth and the constraint value can be used as calculation conditions and input into the first preset algorithm to calculate the first path.
S102：若第一路径对应的标签栈列表的深度小于或等于栈深约束值，则输出第一路径；S102: If the depth of the label stack list corresponding to the first path is less than or equal to the stack depth constraint value, output the first path;
需要说明的是，通过将MSD输入第一预设算法，作为计算约束条件，可以通过第一预设算法直接结算得到标签栈列表深度小于或等于MSD的第一路径。It should be noted that, by inputting the MSD into the first preset algorithm, as a calculation constraint, the first path whose label stack list depth is less than or equal to the MSD can be directly settled through the first preset algorithm.
根据本发明实施例的针对具有栈深约束的路径计算方法，可以通过将栈深约束值输入第一预设算法，作为计算约束条件，直接计算得到标签栈深列表小于等于栈深约束的第一路径，从而极大提高了计算具有栈深约束值的路径成功率。According to the method for calculating the path with stack depth constraint according to the embodiment of the present invention, the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label stack depth list can be directly calculated to be less than or equal to the first value of the stack depth constraint. Path, which greatly improves the success rate of calculating paths with stack depth constraints.
在本发明的一些实施例中，如图1所示，所述方法还包括：S103：在所述第一预设算法无法输出所述第一路径时，采用第二预设算法计算不考虑栈深约束值的第二路径，并对第二路径对应的标签栈列表进行压缩，使压缩后的标签栈列表的深度小于等于栈深约束值，并输出压缩后的标签栈列表对应的路径。In some embodiments of the present invention, as shown in FIG. 1, the method further includes: S103: when the first preset algorithm cannot output the first path, the second preset algorithm is used to calculate without considering the stack The second path of the deep constraint value is compressed, and the label stack list corresponding to the second path is compressed so that the depth of the compressed label stack list is less than or equal to the stack depth constraint value, and the path corresponding to the compressed label stack list is output.
需要说明的是，通过第一预设算法可能无法直接计算得到标签列表深度小于或等于MSD的第一路径。当通过第一预设算法无法直接计算得到标签栈列表的深度小于或等于MSD时，可以通过第二预设算法先计算不考虑MSD的路径并得到第二路径，随后对第二路径的标签栈列表进行压缩，得到标签栈列表深度小于等于MSD的路径。It should be noted that the first path whose label list depth is less than or equal to MSD may not be directly calculated through the first preset algorithm. When the depth of the label stack list cannot be directly calculated by the first preset algorithm to be less than or equal to MSD, the second preset algorithm can be used to first calculate the path that does not consider the MSD and obtain the second path, and then the label stack of the second path The list is compressed to obtain a path whose label stack list depth is less than or equal to MSD.
根据本发明的一些实施例，对第二路径对应的标签栈列表进行压缩，包括：将标签列表中的至少部分链路标签替换为相应的节点标签，以降低标签栈列表深度。According to some embodiments of the present invention, compressing the label stack list corresponding to the second path includes: replacing at least part of the link labels in the label list with corresponding node labels to reduce the depth of the label stack list.
也就是说，可以将标签列表中的全部链路标签替换为相应的节点标签， 也可以是将标签列表中的部分链路标签替换为相应的节点标签。由此，可以降低标签列表深度。That is, all link labels in the label list can be replaced with corresponding node labels, or part of the link labels in the label list can be replaced with corresponding node labels. As a result, the depth of the tag list can be reduced.
如图4所示，若MSD为2，假设通过第二预设算法计算不考虑MSD得到节点1到节点4的第二路径为：1->2->5->3->4，对应的标签列表为{“1->2”，“2->5”，“5->3”，“3->4”}，栈深为4，不满足MSD约束要求。对第二路径的标签列表进行压缩，将标签列表中的链路标签替换为相应的节点标签得到标签栈列表为{“5”，“4”}，栈深为2，满足MSD约束要求。解释为，请求的完整路径分为了两部分，一部分是起始节点1到节点5的最短路径1->2->5，另一部分是节点5到节点4的最短路径5->4->3。As shown in Figure 4, if the MSD is 2, assuming that the second path from node 1 to node 4 is obtained by calculating the second preset algorithm without considering MSD, the second path from node 1 to node 4 is: 1->2->5->3->4, the corresponding The label list is {"1->2", "2->5", "5->3", "3->4"}, and the stack depth is 4, which does not meet the MSD constraint requirements. The label list of the second path is compressed, and the link label in the label list is replaced with the corresponding node label. The label stack list is {"5", "4"}, and the stack depth is 2, which meets the MSD constraint requirements. The explanation is that the complete path of the request is divided into two parts, one part is the shortest path 1->2->5 from the starting node 1 to node 5, and the other part is the shortest path 5->4->3 from node 5 to node 4 .
在本发明的一些实施例，方法还可以包括：In some embodiments of the present invention, the method may further include:
在进行第一路径计算之前，准备路径计算资源；Before performing the first path calculation, prepare path calculation resources;
基于路径计算资源，进行第一路径或第二路径的计算。Based on the path calculation resources, the first path or the second path is calculated.
可以理解的是，通过在计算路径之前，预先准备路径计算资源，可以提高路径计算效率。It can be understood that by pre-preparing path calculation resources before calculating the path, the path calculation efficiency can be improved.
可选地，准备路径计算资源包括：Optionally, preparing path calculation resources includes:
向控制器上报网络拓扑信息；Report network topology information to the controller;
基于网络拓扑信息进行路径缓存计算以得到路径准备资源。Perform path cache calculation based on network topology information to obtain path preparation resources.
例如，如图2所示，在进行路径计算之前，首先可以基于转发设备层面链路权值进行路径缓存，当控制器第一次启动或者重启时，转发设备通过协议上报给控制器每个IGP域的网络拓扑信息，控制器对IGP域进行路径缓存计算。由此，当进行路径计算时，可以直接从缓存中读取两节点之间的最短路径，提高了路径计算效率。For example, as shown in Figure 2, before path calculation, path caching can be performed based on the link weight of the forwarding device level. When the controller starts or restarts for the first time, the forwarding device reports to each IGP of the controller through the protocol. For the network topology information of the domain, the controller performs path cache calculation for the IGP domain. Therefore, when performing path calculation, the shortest path between two nodes can be directly read from the cache, which improves the efficiency of path calculation.
在本发明的一些实施例，第一预设算法为贝尔曼(Bellman)算法，第二预设算法为迪杰斯特拉(Dijkstra)算法或弗洛伊德(Floyed)算法。In some embodiments of the present invention, the first preset algorithm is Bellman's algorithm, and the second preset algorithm is Dijkstra's algorithm or Floyed's algorithm.
需要说明的是，使用Bellman算法计算带有MSD约束的最优路径，Bellman算法作为最短路径算法的一种，与最大跳数约束下的算路天然适配，这也是其它路径算法所不具备的。使用Bellman计算得到的标签栈列表深度等于路径中所有链路条数总数，此时标签栈列表中所有标签都为链路的Adj-SID。当标签列表栈深小于等于MSD时，认为路经计算成功，返回结果，算法到此结束。It should be noted that the Bellman algorithm is used to calculate the optimal path with MSD constraints. As a shortest path algorithm, the Bellman algorithm naturally adapts to the path calculation under the maximum hop number constraint, which is also not available in other path algorithms . The depth of the label stack list calculated by Bellman is equal to the total number of all links in the path. At this time, all the labels in the label stack list are the Adj-SID of the link. When the label list stack depth is less than or equal to MSD, the path calculation is considered successful, the result is returned, and the algorithm ends.
当采用Bellman无法计算得到标签列表栈深小于等于MSD时，首先可以选用普通路径算法，如Dijkstra算法或Floyed算法等计算出一条不考虑MSD约束的最优路径，然后，使用严格LEA算法对该条路径进行压缩，思路为使用Node-SID来代替批量的Adj-SID。值得注意的是，利用Node-SID来引导路由转发路径时，当全网路径缓存中查询到两点之间最短路径只有一条时，才会使用Node-SID来代替批量的Adj-SID，这样可以保证标签栈列表中的Node-SID和Adj-SID元素可以表示唯一一条完整的起始节点到终节点的路径。当标签栈深小于等于MSD时，认为路径计算成功，返回结果，算法至此结束。When Bellman cannot calculate that the label list stack depth is less than or equal to MSD, you can first use ordinary path algorithms, such as Dijkstra algorithm or Floyed algorithm, to calculate an optimal path that does not consider MSD constraints, and then use strict LEA algorithm for this The path is compressed, and the idea is to use Node-SID instead of batch Adj-SID. It is worth noting that when using Node-SID to guide the routing and forwarding path, when there is only one shortest path between two points in the path cache of the entire network, Node-SID will be used instead of batch Adj-SID. Ensure that the Node-SID and Adj-SID elements in the label stack list can represent the only complete path from the start node to the end node. When the label stack depth is less than or equal to MSD, the path calculation is considered successful, the result is returned, and the algorithm ends.
或者，首先使用普通路径算法如Dijkstra、Floyed等计算出一条不考虑MSD约束的最优路径，同样使用Node-SID来批量代替的Adj-SID，与上述方法不同的是，利用Node-SID来引导转发路径时，当全网路径缓存中查询到两点之间存在多条等价最短路径时，即ECMP场景，也会使用Node-SID来代替批量的Adj-SID，此时，与严格LEA相反，标签栈列表中的Node-SID和Adj-SID元素不能做到表示唯一一条完整的起始节点到终节点的路径。当标签栈深小于等于MSD时，认为路径计算成功，返回结果，若标签栈深大于MSD，路径计算失败，返回失败结果。Or, first use ordinary path algorithms such as Dijkstra, Floyed, etc. to calculate an optimal path that does not consider MSD constraints, and also use Node-SID to replace Adj-SID in batches. Different from the above method, use Node-SID to guide When forwarding paths, when there are multiple equivalent shortest paths between two points in the query of the entire network path cache, that is, in ECMP scenarios, Node-SID will also be used instead of batch Adj-SID. In this case, it is contrary to strict LEA , The Node-SID and Adj-SID elements in the label stack list cannot represent the only complete path from the start node to the end node. When the label stack depth is less than or equal to MSD, it is considered that the path calculation is successful and the result is returned. If the label stack depth is greater than MSD, the path calculation fails and a failed result is returned.
需要说明的是，根据本发明实施例中的针对具有栈深约束的路径计算 方法可以应用于SDN(Software Defined Network，软件定义网络)控制器进行SR(Segment Routing)标签路径计算，有效的压缩Segment Routing路径标签。具体步骤如图2所示：It should be noted that the method for path calculation with stack depth constraints in the embodiment of the present invention can be applied to an SDN (Software Defined Network) controller to perform SR (Segment Routing) label path calculations, effectively compressing segments Routing route label. The specific steps are shown in Figure 2:
S11：转发层网络拓扑状态上报，转发层会有多个IGP域，每个IGP域都对应有如图4所示的拓扑结构，当设备工作时，需要通过通信协议将每个IGP域的拓扑结构上报给控制器；S11: The forwarding layer network topology status report. The forwarding layer will have multiple IGP domains. Each IGP domain corresponds to the topology shown in Figure 4. When the device is working, the topology of each IGP domain needs to be changed through the communication protocol. Report to the controller;
S12：控制器进行带宽资源的初始化，将S11初始化的链路信息，记录到带宽管理，为每条链路初始化带宽资源信息，记录好最大、已用、未用的带宽资源，并算路时链路可行性判断提供参考；S12: The controller initializes the bandwidth resource, records the link information initialized by S11 to the bandwidth management, initializes the bandwidth resource information for each link, records the maximum, used, and unused bandwidth resources, and calculates the road time Provide reference for link feasibility judgment;
S13：控制器针对每个IGP域进行全网路径缓存，经过步骤S11和S12，控制器对全局的网络信息有了掌握，针对每个IGP域，控制器会计算出该域内所有节点之间的最短路径并进行存储，每当控制器重启或者拓扑变化时，该步骤都会被触发；S13: The controller caches the entire network path for each IGP domain. After steps S11 and S12, the controller has a grasp of global network information. For each IGP domain, the controller calculates the shortest distance between all nodes in the domain. Path and store, and this step will be triggered whenever the controller restarts or the topology changes;
S14：使用Bellman算法进行带有最大栈深约束下的最优路径计算，当有算路请求到达时，调用该算法，结合带宽管理模块进行算路。若算路成功则直接进行步骤S17返回算路结果，否则进入步骤S15；S14: Use the Bellman algorithm to calculate the optimal path with the maximum stack depth constraint. When a path calculation request arrives, the algorithm is called, and the bandwidth management module is used to calculate the path. If the path calculation is successful, proceed directly to step S17 to return the path calculation result; otherwise, proceed to step S15;
S15：该步骤首先使用普通算路方法，得到一条不满足MSD约束的最优路径，在该既定路径的基础上，使用严格LEA算法对该路径进行压缩；若压缩成功，则直接进入步骤S17返回结果，否则进入步骤S16；S15: This step first uses the common path calculation method to obtain an optimal path that does not meet the MSD constraints. On the basis of the established path, the strict LEA algorithm is used to compress the path; if the compression is successful, go directly to step S17 and return As a result, otherwise go to step S16;
S16：该步骤首先使用普通算路方法，得到一条不满足MSD约束的最优路径，在该既定路径的基础上，使用松散LEA算法对该路径进行压缩；之后进入步骤S17。S16: In this step, a common path calculation method is first used to obtain an optimal path that does not satisfy the MSD constraint. On the basis of the established path, the loose LEA algorithm is used to compress the path; then step S17 is entered.
如图3和图4所示，根据本发明实施例的针对具有栈深约束的路径计 算装置，包括：第一算法模块。As shown in Figures 3 and 4, the device for path calculation with stack depth constraints according to an embodiment of the present invention includes: a first algorithm module.
具体而言，第一算法模块设置为基于栈深约束值，采用第一预设算法计算第一路径。若第一路径对应的标签栈列表的深度小于或等于栈深约束值，则输出第一路径。Specifically, the first algorithm module is set to calculate the first path by using the first preset algorithm based on the stack depth constraint value. If the depth of the label stack list corresponding to the first path is less than or equal to the stack depth constraint value, the first path is output.
根据本发明实施例的针对具有栈深约束的路径计算装置，可以通过将栈深约束值输入第一预设算法，作为计算约束条件，直接计算得到标签列表栈深小于等于栈深约束值的第一路径，从而极大提高了计算具有栈深约束值的路径的效率和成功率。According to the embodiment of the present invention for the path calculation device with stack depth constraint, the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition, and the label list stack depth can be directly calculated to be less than or equal to the first preset algorithm of the stack depth constraint value. One path, thereby greatly improving the efficiency and success rate of calculating paths with stack depth constraints.
在本发明的一些实施例中，装置还包括：第二算法模块。第二算法模块可以设置为在第一算模块无法输出第一路径时，采用第二预设算法计算不考虑栈深约束值的第二路径，并对第二路径对应的标签栈列表进行压缩，使压缩后的标签栈列表的深度小于等于栈深约束值，并输出压缩后的标签栈列表对应的路径。In some embodiments of the present invention, the device further includes: a second algorithm module. The second algorithm module may be configured to use the second preset algorithm to calculate the second path without considering the stack depth constraint value when the first calculation module cannot output the first path, and compress the label stack list corresponding to the second path, Make the depth of the compressed label stack list less than or equal to the stack depth constraint value, and output the path corresponding to the compressed label stack list.
需要说明的是，通过将MSD输入第一预设算法，可以通过第一预设算法直接结算得到标签栈列表深度小于或等于MSD的第一路径，但也可能是，通过第一预设算法无法直接计算得到标签列表深度小于或等于MSD的第一路径。It should be noted that by inputting MSD into the first preset algorithm, the first path with the label stack list depth less than or equal to MSD can be directly settled through the first preset algorithm, but it may also be impossible to use the first preset algorithm Directly calculate the first path whose label list depth is less than or equal to MSD.
也就是说，当通过第一预设算法无法直接计算得到标签栈列表的深度小于或等于MSD时，可以通过第二预设算法先计算不考虑MSD的路径并得到第二路径，随后对第二路径的标签栈列表进行压缩，得到标签栈列表深度小于等于MSD的路径。In other words, when the depth of the label stack list cannot be directly calculated by the first preset algorithm to be less than or equal to MSD, the second preset algorithm can be used to first calculate the path that does not consider MSD and obtain the second path, and then the second path The label stack list of the path is compressed to obtain the path whose label stack list depth is less than or equal to MSD.
根据本发明的一些实施例，第二算法模块对第二路径对应的标签栈列表进行压缩时，具体设置为：将标签列表中的至少部分链路标签替换为相应的节点标签，以降低标签栈列表深度。According to some embodiments of the present invention, when the second algorithm module compresses the label stack list corresponding to the second path, it is specifically set to replace at least part of the link labels in the label list with corresponding node labels to reduce the label stack. List depth.
也就是说，可以将标签列表中的全部链路标签替换为相应的节点标签，也可以是将标签列表中的部分链路标签替换为相应的节点标签。由此，可以降低标签列表深度。That is, all link labels in the label list can be replaced with corresponding node labels, or part of the link labels in the label list can be replaced with corresponding node labels. As a result, the depth of the tag list can be reduced.
如图4所示，若MSD为2，假设通过第二预设算法计算不考虑MSD得到节点1到节点4的第二路径为：1->2->5->3->4，对应的标签列表为{“1->2”，“2->5”，“5->3”，“3->4”}，栈深为4，不满足MSD约束要求。对第二路径的标签列表进行压缩，将标签列表中的链路标签替换为相应的节点标签得到标签栈列表为{“5”，“4”}，栈深为2，满足MSD约束要求。解释为，请求的完整路径分为了两部分，一部分是起始节点1到节点5的最短路径1->2->5，另一部分是节点5到节点4的最短路径5->4->3。As shown in Figure 4, if the MSD is 2, assuming that the second path from node 1 to node 4 is obtained by calculating the second preset algorithm without considering MSD, the second path from node 1 to node 4 is: 1->2->5->3->4, the corresponding The label list is {"1->2", "2->5", "5->3", "3->4"}, and the stack depth is 4, which does not meet the MSD constraint requirements. The label list of the second path is compressed, and the link label in the label list is replaced with the corresponding node label. The label stack list is {"5", "4"}, and the stack depth is 2, which meets the MSD constraint requirements. The explanation is that the complete path of the request is divided into two parts, one part is the shortest path 1->2->5 from the starting node 1 to node 5, and the other part is the shortest path 5->4->3 from node 5 to node 4 .
如图3和图4所示，在本发明的一些实施例，装置还可以包括：资源准备模块，资源准备模块设置为在进行第一路径计算之前，准备路径计算资源；由此，可以基于路径计算资源，进行第一路径或第二路径的计算。As shown in Figures 3 and 4, in some embodiments of the present invention, the device may further include: a resource preparation module, which is configured to prepare path calculation resources before performing the first path calculation; Computing resources to perform the calculation of the first path or the second path.
可以理解的是，通过在计算路径之前，预先准备路径计算资源，可以提高路径计算效率。It can be understood that by pre-preparing path calculation resources before calculating the path, the path calculation efficiency can be improved.
如图3和图4所示，根据本发明的一些实施例，资源准备模块可以包括：拓扑加载模块和路径缓存模块As shown in Figures 3 and 4, according to some embodiments of the present invention, the resource preparation module may include: a topology loading module and a path caching module
拓扑加载模块可以设置为向控制器上报网络拓扑信息；The topology loading module can be set to report network topology information to the controller;
路径缓存模块可以设置为基于网络拓扑信息进行路径缓存计算以得到路径计算资源。The path cache module may be configured to perform path cache calculation based on network topology information to obtain path calculation resources.
例如，如图2所示，在进行路径计算之前，首先可以基于转发设备层面链路权值进行路径缓存，当控制器第一次启动或者重启时，转发设备通过协议上报给控制器每个IGP域的网络拓扑信息，控制器对IGP域进行路径缓存计算。由此，当进行路径计算时，可以直接从缓存中读取两节点之 间的最短路径，提高了路径计算效率。For example, as shown in Figure 2, before path calculation, path caching can be performed based on the link weight of the forwarding device level. When the controller starts or restarts for the first time, the forwarding device reports to each IGP of the controller through the protocol. For the network topology information of the domain, the controller performs path cache calculation for the IGP domain. Therefore, when performing path calculation, the shortest path between two nodes can be directly read from the cache, which improves the efficiency of path calculation.
在本发明的一些实施例，第一预设算法可以为Bellman算法，第二预设算法可以为Dijkstra算法或Floyed算法。In some embodiments of the present invention, the first preset algorithm may be the Bellman algorithm, and the second preset algorithm may be the Dijkstra algorithm or the Floyed algorithm.
需要说明的是，使用Bellman算法计算带有MSD约束的最优路径，Bellman算法作为最短路径算法的一种，与最大跳数约束下的算路天然适配，这也是其它路径算法所不具备的。使用Bellman计算得到的标签栈列表深度等于路径中所有链路条数总数，此时标签栈列表中所有标签都为链路的Adj-SID。当标签列表栈深小于等于MSD时，认为路经计算成功，返回结果，算法到此结束。It should be noted that the Bellman algorithm is used to calculate the optimal path with MSD constraints. As a shortest path algorithm, the Bellman algorithm naturally adapts to the path calculation under the maximum hop number constraint, which is also not available in other path algorithms . The depth of the label stack list calculated by Bellman is equal to the total number of all links in the path. At this time, all the labels in the label stack list are the Adj-SID of the link. When the label list stack depth is less than or equal to MSD, the path calculation is considered successful, the result is returned, and the algorithm ends.
当采用Bellman无法计算得到标签列表栈深小于等于MSD时，首先可以选用普通路径算法，如Dijkstra算法或Floyed算法等计算出一条不考虑MSD约束的最优路径，然后，使用严格LEA算法对该条路径进行压缩，思路为使用Node-SID来代替批量的Adj-SID。值得注意的是，利用Node-SID来引导路由转发路径时，当全网路径缓存中查询到两点之间最短路径只有一条时，才会使用Node-SID来代替批量的Adj-SID，这样可以保证标签栈列表中的Node-SID和Adj-SID元素可以表示唯一一条完整的起始节点到终节点的路径。当标签栈深小于等于MSD时，认为路径计算成功，返回结果，算法至此结束。When Bellman cannot calculate that the label list stack depth is less than or equal to MSD, you can first use ordinary path algorithms, such as Dijkstra algorithm or Floyed algorithm, to calculate an optimal path that does not consider MSD constraints, and then use strict LEA algorithm for this The path is compressed, and the idea is to use Node-SID instead of batch Adj-SID. It is worth noting that when using Node-SID to guide the routing and forwarding path, when there is only one shortest path between two points in the path cache of the entire network, Node-SID will be used instead of batch Adj-SID. Ensure that the Node-SID and Adj-SID elements in the label stack list can represent the only complete path from the start node to the end node. When the label stack depth is less than or equal to MSD, the path calculation is considered successful, the result is returned, and the algorithm ends.
或者，首先使用普通路径算法如Dijkstra、Floyed等计算出一条不考虑MSD约束的最优路径，同样使用Node-SID来批量代替的Adj-SID，与上述方法不同的是，利用Node-SID来引导转发路径时，当全网路径缓存中查询到两点之间存在多条等价最短路径时，即ECMP场景，也会使用Node-SID来代替批量的Adj-SID，此时，与严格LEA相反，标签栈列表中的Node-SID和Adj-SID元素不能做到表示唯一一条完整的起始节点到 终节点的路径。当标签栈深小于等于MSD时，认为路径计算成功，返回结果，若标签栈深大于MSD，路径计算失败，返回失败结果。Or, first use ordinary path algorithms such as Dijkstra, Floyed, etc. to calculate an optimal path that does not consider MSD constraints, and also use Node-SID to replace Adj-SID in batches. Different from the above method, use Node-SID to guide When forwarding paths, when there are multiple equivalent shortest paths between two points in the query of the entire network path cache, that is, in ECMP scenarios, Node-SID will also be used instead of batch Adj-SID. In this case, it is contrary to strict LEA , The Node-SID and Adj-SID elements in the label stack list cannot represent the only complete path from the start node to the end node. When the label stack depth is less than or equal to MSD, it is considered that the path calculation is successful and the result is returned. If the label stack depth is greater than MSD, the path calculation fails and a failed result is returned.
根据本发明实施例的分段路由路径标签处理装置，包括：存储器、处理器及存储在存储器上并可在处理器上运行的计算机程序，计算机程序被处理器执行时实现如上述的方法的步骤。The segment routing path label processing device according to the embodiment of the present invention includes: a memory, a processor, and a computer program stored in the memory and running on the processor. The computer program is executed by the processor to implement the steps of the above method .
根据本发明实施例的分段路由路径标签处理装置，首先可以通过Bellman算法计算具有栈深约束的路径，若得到符合栈深约束值条件的第一路径，则输出第一路径；若得不到符合栈深约束值条件的第一路径，则通过基本算法先计算不考虑栈深约束值进行路径计算，并对计算得到的第二路径的标签栈列表进行压缩，得到符合栈深约束值条件的路径，从而极大提高了计算具有栈深约束值的路径成功率。According to the segment routing path label processing device of the embodiment of the present invention, the path with the stack depth constraint can be calculated by Bellman algorithm first, and if the first path that meets the stack depth constraint value condition is obtained, then the first path is output; The first path that meets the stack depth constraint value condition is first calculated by the basic algorithm without considering the stack depth constraint value for path calculation, and the calculated label stack list of the second path is compressed to obtain the stack depth constraint value condition Path, which greatly improves the success rate of calculating paths with stack depth constraints.
根据本发明实施例的计算机存储介质，计算机存储介质上存储有计算机程序，计算机程序被处理器执行时实现如上述的针对具有栈深约束的路径计算方法的步骤。According to the computer storage medium of the embodiment of the present invention, a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, the steps of the above-mentioned path calculation method with stack depth constraints are implemented.
根据本发明实施例的计算机存储介质，首先可以通过Bellman算法计算具有栈深约束的路径，若得到符合栈深约束值条件的第一路径，则输出第一路径；若得不到符合栈深约束值条件的第一路径，则通过基本算法先计算不考虑栈深约束值进行路径计算，并对计算得到的第二路径的标签栈列表进行压缩，得到符合栈深约束值条件的路径，从而极大提高了计算具有栈深约束值的路径成功率。According to the computer storage medium of the embodiment of the present invention, the path with the stack depth constraint can be calculated by Bellman algorithm. If the first path that meets the stack depth constraint value condition is obtained, the first path is output; if the stack depth constraint is not obtained For the first path of the value condition, the basic algorithm is used to first calculate the path calculation without considering the stack depth constraint value, and the calculated label stack list of the second path is compressed to obtain the path that meets the stack depth constraint value. It greatly improves the success rate of calculating paths with stack depth constraints.
下面以具体的实施例详细描述根据本发明的针对具有栈深约束的路径计算方法：The following specific embodiments describe in detail the path calculation method with stack depth constraint according to the present invention:
如图4所示为一个具有10个节点、13条链路的网络拓扑，每条链路有它对应的权值，令链路A->B的Adj-SID为“A->B”，令节点A的Node-SID为“A”，为了简单说明问题，忽略了链路的带宽资源信息，但不影响算法的主流程。认为该网络拓扑为单个IGP域，这里以单个IGP域进行展示流程。Figure 4 shows a network topology with 10 nodes and 13 links. Each link has its corresponding weight. Let the Adj-SID of link A->B be "A->B", Let the Node-SID of node A be "A". In order to explain the problem simply, the bandwidth resource information of the link is ignored, but the main flow of the algorithm is not affected. The network topology is considered to be a single IGP domain, and a single IGP domain is used here for the presentation process.
通过转发层面上报，控制器获得了单个IGP网络拓扑，以链路权值为准则，进行全局路径缓存，如下表所示(表中只列出了部分结果作为示例)：Through reporting at the forwarding level, the controller obtains a single IGP network topology, and uses the link weight as the criterion to perform global path caching, as shown in the following table (only some results are listed as examples in the table):
Figure PCTCN2020099017-appb-000001
Figure PCTCN2020099017-appb-000001
假设当前有一个算路请求，起点为节点1，终点为节点4，当该请求携带的最大栈深约束为一下几种情况时，分别讨论：Assuming that there is a path calculation request, the starting point is node 1 and the end point is node 4. When the maximum stack depth constraint carried by the request is the following situations, discuss separately:
(1)最大栈深约束MSD＝4时：此时使用图2中的步骤S14中的Bellman算法可得到最优路径为1->2->5->3->4或者1->6->8->3->4，直接算路成功，返回结果，假设为前者，此时标签栈列表为{“1->2”,“2->5”，“5->3”，“3->4”}。值得注意的是，此时即使是使用普通算路算法，也可以得到满足MSD约束的最优路径。而本发明实施例中提出的标签压缩方法就是为了解决工程中MSD约束比较小的情况，事实上，实际工程中MSD都不大。(1) When the maximum stack depth constraint MSD=4: At this time, the Bellman algorithm in step S14 in Figure 2 can be used to obtain the optimal path as 1->2->5->3->4 or 1->6- >8->3->4, the direct calculation is successful, and the result is returned. Assuming the former, the label stack list is {"1->2", "2->5", "5->3", " 3->4”}. It is worth noting that at this time, even if the common path calculation algorithm is used, the optimal path that satisfies the MSD constraint can be obtained. The label compression method proposed in the embodiment of the present invention is to solve the situation that the MSD constraint in the project is relatively small. In fact, the MSD in the actual project is not large.
(2)最大栈深约束MSD＝3时：此时使用图2中步骤S14中的Bellman算法可得到跳数为3时的最优路径：1->6->7->4，算路成功，返回结果，此时标签栈列表为{“1->6”,“6->7”,“7->4”}；而使用普通算路算法得到的最 优路径还是1->2->5->3->4或者1->6->8->3->4，此时跳数为4大于MSD，算路失败。(2) When the maximum stack depth constraint MSD=3: At this time, the Bellman algorithm in step S14 in Figure 2 can be used to obtain the optimal path when the number of hops is 3: 1->6->7->4, the calculation is successful , Returns the result, the label stack list at this time is {"1->6", "6->7", "7->4"}; and the optimal path obtained by the ordinary path calculation algorithm is still 1->2- >5->3->4 or 1->6->8->3->4, when the hop count is 4 greater than MSD, the path calculation fails.
(3)最大栈深约束MSD＝2时：此时使用图2中步骤S14中的Bellman算法，算路失败，因为在最大跳数约束为2的情况下，无可行路径；接下来使用普通算路算大得到一条不含有跳数约束的最优路径，假设该路径为：1->2->5->3->4，使用严格LEA算法，得到的标签栈列表为{“5”，“4”}，满足MSD约束要求。解释为，请求的完整路径分为了两部分，一部分是起始节点1到节点5的最短路径1->2->5，另一部分是节点5到节点4的最短路径5->4->3，这也是充分利用了Segment Routing技术的特点，即通过Node-SID来引导路由沿着最短路径方向转发。值得注意的是，此时的完整路径是可以唯一表示的，转发设备进行路由转发时候路径确定为1->2->5->3->4。(3) When the maximum stack depth constraint MSD=2: At this time, the Bellman algorithm in step S14 in Fig. 2 is used, and the path calculation fails, because there is no feasible path when the maximum hops constraint is 2; Road calculation is large and obtains an optimal path without hop constraints. Assuming that the path is: 1->2->5->3->4, using the strict LEA algorithm, the resulting label stack list is {"5", "4"}, to meet the MSD constraint requirements. It is explained that the complete path of the request is divided into two parts, one part is the shortest path 1->2->5 from the starting node 1 to node 5, and the other part is the shortest path 5->4->3 from node 5 to node 4 , This also makes full use of the characteristics of the Segment Routing technology, that is, the Node-SID is used to guide the routing along the shortest path. It is worth noting that the complete path at this time can be uniquely represented, and the path is determined as 1->2->5->3->4 when the forwarding device performs routing and forwarding.
(4)最大栈深约束MSD＝1时：使用图2中步骤S14中的Bellman算法和步骤S15中的严格LEA算法都不能得到满足要求的标签栈列表。而使用图2中步骤S16中松散LEA算法，得到的标签栈列表为{“4”}，算路成功。解释为，转发设备进行路由转发的时候将从节点1开始沿着到节点4的最短路径进行，值得注意的是，此时节点1到节点4的最短路径有两条：1->2->5->3->4和1->6->8->3->4，所以并不能唯一标示转发路径。(4) When the maximum stack depth constraint MSD=1: neither the Bellman algorithm in step S14 nor the strict LEA algorithm in step S15 in FIG. 2 can obtain a label stack list that meets the requirements. Using the loose LEA algorithm in step S16 in Figure 2, the label stack list obtained is {"4"}, and the path calculation is successful. It is explained that when the forwarding device performs routing and forwarding, it will start from node 1 and proceed along the shortest path to node 4. It is worth noting that there are two shortest paths from node 1 to node 4 at this time: 1->2-> 5->3->4 and 1->6->8->3->4, so the forwarding path cannot be uniquely indicated.
本发明实施例综合了三种基于栈深约束的算路方案，极大提高了算路成功率。The embodiment of the present invention integrates three path calculation schemes based on stack depth constraints, which greatly improves the path calculation success rate.
通过具体实施方式的说明，应当可对本发明为达成预定目的所采取的技术手段及功效得以更加深入且具体的了解，然而所附图示仅是提供参考与说明之用，并非用来对本发明加以限制。Through the description of the specific embodiments, it should be possible to have a more in-depth and specific understanding of the technical means and effects adopted by the present invention to achieve the intended purpose. However, the attached drawings are only for reference and explanation, and are not used to describe the present invention. limit.
工业实用性Industrial applicability
如上所述，本发明实施例提供的一种针对具有栈深约束的路径计算方法及装置具有以下有益效果：可以通过将栈深约束值输入第一预设算法，作为计算约束条件，直接计算得到标签列表栈深度小于等于栈深约束值的第一路径，提高了计算具有栈深约束值的路径的效率和成功率。As described above, the method and device for path calculation with stack depth constraint provided by the embodiments of the present invention have the following beneficial effects: the stack depth constraint value can be input into the first preset algorithm as the calculation constraint condition and directly calculated The first path whose label list stack depth is less than or equal to the stack depth constraint value improves the efficiency and success rate of calculating the path with the stack depth constraint value.

Claims (12)

  1. 一种针对具有栈深约束的路径计算方法，包括：A method for path calculation with stack depth constraints, including:
    基于栈深约束值，采用第一预设算法计算第一路径；Based on the stack depth constraint value, the first preset algorithm is used to calculate the first path;
    若所述第一路径对应的标签栈列表的深度小于或等于所述栈深约束值，则输出所述第一路径。If the depth of the label stack list corresponding to the first path is less than or equal to the stack depth constraint value, output the first path.
  2. 根据权利要求1所述的针对具有栈深约束的路径计算方法，其中，所述方法还包括：The method for path calculation with stack depth constraints according to claim 1, wherein the method further comprises:
    在所述第一预设算法无法输出所述第一路径时，采用第二预设算法计算不考虑所述栈深约束值的第二路径，并对所述第二路径对应的标签栈列表进行压缩，使压缩后的所述标签栈列表的深度小于等于所述栈深约束值，并输出压缩后的所述标签栈列表对应的路径。When the first preset algorithm cannot output the first path, the second preset algorithm is used to calculate the second path that does not consider the stack depth constraint value, and the label stack list corresponding to the second path is calculated Compression makes the depth of the compressed label stack list less than or equal to the stack depth constraint value, and outputs the path corresponding to the compressed label stack list.
  3. 根据权利要求2所述的针对具有栈深约束的路径计算方法，其中，对所述第二路径对应的标签栈列表进行压缩，包括：The method for path calculation with stack depth constraints according to claim 2, wherein compressing the label stack list corresponding to the second path comprises:
    将所述标签列表中的至少部分链路标签替换为相应的节点标签，以降低标签栈列表深度。Replace at least part of the link labels in the label list with corresponding node labels to reduce the depth of the label stack list.
  4. 根据权利要求2所述的针对具有栈深约束的路径计算方法，其中，所述方法还包括：The method for path calculation with stack depth constraints according to claim 2, wherein the method further comprises:
    在进行第一路径计算之前，向控制器上报网络拓扑信息；Before performing the first path calculation, report network topology information to the controller;
    基于所述网络拓扑信息进行路径缓存计算；Performing path cache calculation based on the network topology information;
    基于所述路径缓存计算数据，进行所述第一路径或所述第二路径的计算。Perform calculation of the first path or the second path based on the path cache calculation data.
  5. 根据权利要求2所述的针对具有栈深约束的路径计算方法，其中，The method for path calculation with stack depth constraints according to claim 2, wherein:
    所述第一预设算法为贝尔曼算法，所述第二预设算法为迪杰斯特拉算法或弗洛伊德算法。The first preset algorithm is Bellman's algorithm, and the second preset algorithm is Dijkstra's algorithm or Freud's algorithm.
  6. 一种针对具有栈深约束的路径计算装置，包括：A path calculation device with stack depth constraint includes:
    第一算法模块，设置为基于栈深约束值，采用第一预设算法计算第一路径；The first algorithm module is set to use the first preset algorithm to calculate the first path based on the stack depth constraint value;
    若所述第一路径对应的标签栈列表的深度小于或等于所述栈深约束值，则输出所述第一路径。If the depth of the label stack list corresponding to the first path is less than or equal to the stack depth constraint value, output the first path.
  7. 根据权利要求6所述的针对具有栈深约束的路径计算装置，其中，所述装置还包括：The device for path calculation with stack depth constraints according to claim 6, wherein the device further comprises:
    第二算法模块，设置为在所述第一算模块无法输出所述第一路径时，采用第二预设算法计算不考虑所述栈深约束值的第二路径，并对所述第二路径对应的标签栈列表进行压缩，使压缩后的所述标签栈列表的深度小于等于所述栈深约束值，并输出压缩后的所述标签栈列表对应的路径。The second algorithm module is configured to use a second preset algorithm to calculate a second path that does not consider the stack depth constraint value when the first calculation module cannot output the first path, and compare the second path The corresponding tag stack list is compressed so that the depth of the compressed tag stack list is less than or equal to the stack depth constraint value, and the path corresponding to the compressed tag stack list is output.
  8. 根据权利要求7所述的针对具有栈深约束的路径计算装置，其中，所述第二算法模块对所述第二路径对应的标签栈列表进行压缩时，具体设置为：8. The device for calculating paths with stack depth constraints according to claim 7, wherein when the second algorithm module compresses the label stack list corresponding to the second path, the specific setting is:
    将所述标签列表中的至少部分链路标签替换为相应的节点标签，以降低标签栈列表深度。Replace at least part of the link labels in the label list with corresponding node labels to reduce the depth of the label stack list.
  9. 根据权利要求7所述的针对具有栈深约束的路径计算装置，其中，所述装置还包括：The device for path calculation with stack depth constraint according to claim 7, wherein the device further comprises:
    拓扑加载模块，设置为在进行第一路径计算之前，向控制器上报网络拓扑信息；The topology loading module is set to report network topology information to the controller before performing the first path calculation;
    路径缓存模块，设置为基于所述网络拓扑信息进行路径缓存计算；A path cache module, configured to perform path cache calculation based on the network topology information;
    所述第一算法模块和所述第二算法模块基于所述路径缓存计算数据，进行所述第一路径和所述第二路径的计算。The first algorithm module and the second algorithm module calculate the first path and the second path based on the path cache calculation data.
  10. 根据权利要求7所述的针对具有栈深约束的路径计算装置，其中，The device for path calculation with stack depth constraint according to claim 7, wherein:
    所述第一预设算法为贝尔曼算法，所述第二预设算法为迪杰斯特拉算法或弗洛伊德算法。The first preset algorithm is Bellman's algorithm, and the second preset algorithm is Dijkstra's algorithm or Freud's algorithm.
  11. 一种分段路由路径标签处理装置，包括：存储器、处理器及存储在所述存储器上并可在所述处理器上运行的计算机程序，所述计算机程序被所述处理器执行时实现如权利要求1至5中任一项所述的针对具有栈深约束的路径计算方法的步骤。A segmented routing path label processing device, comprising: a memory, a processor, and a computer program stored in the memory and capable of running on the processor. The computer program is executed by the processor to achieve The steps of the path calculation method with stack depth constraint described in any one of requirements 1 to 5.
  12. 一种计算机存储介质，所述计算机存储介质上存储有计算机程序，所述计算机程序被处理器执行时实现如权利要求1至5中任一项所述的针对具有栈深约束的路径计算方法的步骤。A computer storage medium having a computer program stored on the computer storage medium, and when the computer program is executed by a processor, implements the method for path calculation with stack depth constraints according to any one of claims 1 to 5 step.
PCT/CN2020/099017 2019-08-08 2020-06-29 Route calculation method involving stack depth constraint, and device WO2021022944A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201910728470.2 2019-08-08
CN201910728470.2A CN112350935B (en) 2019-08-08 2019-08-08 Path calculation method and device for path with stack depth constraint

Publications (1)

Publication Number Publication Date
WO2021022944A1 true WO2021022944A1 (en) 2021-02-11

Family

ID=74367428

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/099017 WO2021022944A1 (en) 2019-08-08 2020-06-29 Route calculation method involving stack depth constraint, and device

Country Status (2)

Country Link
CN (1) CN112350935B (en)
WO (1) WO2021022944A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113242179A (en) * 2021-05-10 2021-08-10 Ut斯达康通讯有限公司 SDN-based SR path calculation and label stack generation method and SDN controller
WO2023155068A1 (en) * 2022-02-16 2023-08-24 Telefonaktiebolaget Lm Ericsson (Publ) Communication device, sdn controller, and methods therein for facilitating path computation

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113132234A (en) * 2019-12-27 2021-07-16 华为技术有限公司 Tunnel segmentation method and device and data transmission system
CN113824632B (en) * 2021-09-03 2023-04-18 比威网络技术有限公司 Method and device for compressing path points in safe hierarchical multipath routing

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105471737A (en) * 2014-09-05 2016-04-06 华为技术有限公司 Tag stack compression method and device and tag stack decompression method and device
WO2017198319A1 (en) * 2016-05-20 2017-11-23 Telefonaktiebolaget Lm Ericsson (Publ) Method and apparatus for segment routing and rsvp-te routing in transport sdn networks
CN108055878A (en) * 2015-07-02 2018-05-18 瑞典爱立信有限公司 Using Border Gateway Protocol maximum segment identifier depth is disclosed to applications
CN109450456A (en) * 2018-10-30 2019-03-08 南京大学 A kind of adaptive storehouse interpretation method and system based on polarization code

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100334837C (en) * 2003-12-24 2007-08-29 华为技术有限公司 A method for assigning path bandwidth in bearing control layer
CN104143991B (en) * 2013-05-06 2018-02-06 华为技术有限公司 The interpretation method and device of polarity Polar codes
EP3497893B1 (en) * 2016-08-15 2020-11-04 Telefonaktiebolaget LM Ericsson (publ) Segment routing based on maximum segment identifier depth
US20180343191A1 (en) * 2017-05-25 2018-11-29 Fang Hao Hop constrained widest path for segment routing

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105471737A (en) * 2014-09-05 2016-04-06 华为技术有限公司 Tag stack compression method and device and tag stack decompression method and device
CN108055878A (en) * 2015-07-02 2018-05-18 瑞典爱立信有限公司 Using Border Gateway Protocol maximum segment identifier depth is disclosed to applications
WO2017198319A1 (en) * 2016-05-20 2017-11-23 Telefonaktiebolaget Lm Ericsson (Publ) Method and apparatus for segment routing and rsvp-te routing in transport sdn networks
CN109450456A (en) * 2018-10-30 2019-03-08 南京大学 A kind of adaptive storehouse interpretation method and system based on polarization code

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113242179A (en) * 2021-05-10 2021-08-10 Ut斯达康通讯有限公司 SDN-based SR path calculation and label stack generation method and SDN controller
WO2023155068A1 (en) * 2022-02-16 2023-08-24 Telefonaktiebolaget Lm Ericsson (Publ) Communication device, sdn controller, and methods therein for facilitating path computation

Also Published As

Publication number Publication date
CN112350935A (en) 2021-02-09
CN112350935B (en) 2023-03-24

Similar Documents

Publication Publication Date Title
WO2021022944A1 (en) Route calculation method involving stack depth constraint, and device
US10432427B2 (en) Border gateway protocol for communication among software defined network controllers
US9203702B2 (en) Path calculation method
US9049131B2 (en) Network system and load balancing method
WO2018049649A1 (en) Network performance measurement method and device
WO2015106729A1 (en) A load balancing method, device, system and computer storage medium
US11632322B2 (en) Preferred path route graphs in a network
US9832121B1 (en) Next hop instruction associations for forwarding unit programming within a network device
CN108476175B (en) Transfer SDN traffic engineering method and system using dual variables
Zheng et al. Sentinel: Failure recovery in centralized traffic engineering
WO2018103737A1 (en) Method and device for establishing route
US10666562B2 (en) Network path computation method, apparatus, and system
WO2023078150A1 (en) Path calculation method, route calculation device, electronic device, and computer storage medium
US20170222934A1 (en) Maintaining information of te link
CN105357124A (en) MapReduce bandwidth optimization method
JP5782999B2 (en) Route determining device, node device, and route determining method
WO2018090852A1 (en) Link state packet transmission method, and routing node
WO2018095438A1 (en) Method and device for processing equal cost multi-path (ecmp)
WO2018219298A1 (en) Method and device for processing failure of path computation requested by path computation client (pcc)
WO2017063166A1 (en) Method and device for establishing label-switched path circumventing disconnected link
WO2018113460A1 (en) Multi-layer lsp control method and apparatus
WO2018153314A1 (en) Method for positioning lsp with error and pcc and pce
CN107295038A (en) A kind of method and device for setting up interface group
WO2016062071A1 (en) Concurrence processing method, apparatus and system for service creation and increment discovery
WO2016000365A1 (en) Method and apparatus for path computation

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20849559

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20849559

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 20849559

Country of ref document: EP

Kind code of ref document: A1