CN114389996B

CN114389996B - Method and device for SRv SID distribution in multi-topology environment based on resources

Info

Publication number: CN114389996B
Application number: CN202210005948.0A
Authority: CN
Inventors: 何建
Original assignee: Nanjing Third Generation Communication Technology Co ltd; Fiberhome Telecommunication Technologies Co Ltd
Current assignee: Nanjing Third Generation Communication Technology Co ltd; Fiberhome Telecommunication Technologies Co Ltd
Priority date: 2022-01-04
Filing date: 2022-01-04
Publication date: 2023-06-09
Anticipated expiration: 2042-01-04
Also published as: CN114389996A

Abstract

The invention relates to a method and a device for SRv SID allocation in a multi-topology environment based on resources. The method mainly comprises the following steps: dividing SID into topology ID and resource ID; searching corresponding service resources according to the received SID allocation request and allocating the resource IDs; setting the VTN topology bitmap of the request; the assigned SID is returned using a combination of Locator + topology ID + resource ID. The invention can greatly reduce memory occupation and improve allocation and release efficiency when the VTN corresponding to the multi-network slice allocates SIDs in VPN+ application deployment. On the other hand, the invention also solves the problem puzzled in the industry at present, namely the problem of carrying the VTN ID.

Description

Method and device for SRv SID distribution in multi-topology environment based on resources

[ field of technology ]

The invention relates to the field of data communication SRv6, in particular to a SRv SID allocation method and device under a multi-topology environment based on resources.

[ background Art ]

With the deployment of network slicing and VPN (Virtual Private Network ) +services in a SRv (Segment-Routing IPv6, IPv6 Segment Routing) network environment, multiple VTN (Virtual Terminal Network, network virtual terminal) networks are introduced, and each VTN network has its own independent topology and performs Routing according to a specific algorithm (constraint conditions such as delay and packet loss). Each topology on a device node programs an independent Locator (location identification). This results in the assignment of SIDs (Segment Identifier, segment identifiers) on a per topology basis on the device basis.

As shown in fig. 1, a diagram of SRv6 multi-topology network is illustrated: there are two topologies in this network illustrated in the figure, namely the upper (

nodes

1, 2, 3, 4) network topology applying the flex-algo 128 algorithm and the lower (

nodes

5, 6, 7, 8) network topology applying the flex-algo 129 algorithm.

Nodes

0 and 9 exist in two network topologies at the same time, and corresponding equipment nodes have the requirement of distributing SIDs for two different Locator segments in which the two network topologies are located at the same time.

Whether conventional MPLS (Multi-Protocol Label Switching, multiprotocol label switching) label allocation or existing SRv SID allocation is a method for performing resource allocation based on a Locator space, the allocation algorithm is based on a segment+bitmap index allocation release algorithm. When the SID is allocated to multiple locators, more SIDs are allocated, and the problems of low allocation efficiency and high resource occupation are highlighted.

As shown in fig. 2, a conventional SRv SID allocation scheme is shown. First, it is described that: when SID (format is similar to IPv6 address format) is allocated from one Locator segment, the whole Locator segment is divided into an area that has been allocated and an area that has not been allocated, and the SID in the area that has been allocated is occupied by another applicant, and a new SID can be allocated only in the area that has not been allocated. There are two Locator segments, 100:64 and 200:64, respectively, for the same resource, such as vpn1, 100:64, assigned a SID of the END.DT4 type 100:1, and 200:64 assigned a SID of the END.DT4 type 200:2. Thus, the assignment relation between SIDs maintained in the Locator section and service resources is 100:64: 1END.DT4 to vpn1; 200:64 the distribution relation between SID maintained by the Locator section and service resources is as follows: 200:2END.DT4 to vpn1. It can be seen that, for different Locator segments, the existing allocation method needs to maintain allocation relations (SID < - - - > service resources) respectively, which occupies huge memory. The consequences of this are: each time of allocation and release, a plurality of time-consuming management resources of the Locator segments are needed, and the efficiency is low.

In view of this, how to overcome the defects existing in the prior art, and solve the problems of low allocation efficiency and high occupied resources in the multi-topology multi-Locator network environment in the existing SRv SID allocation technology, is a difficult problem to be solved in the technical field.

[ invention ]

In order to meet the above defects or improvement needs of the prior art, the present invention provides a method and a device for SRv SID allocation in a multi-topology environment based on resources, which divide the variable function+structures during SRv SID allocation into two parts: the topology ID and the resource ID are subjected to resource abstraction on the allocation formula, so that the advantage that the resource ID can be applied to a plurality of network topologies only by being allocated once is obtained, and the allocation and release efficiency of SRv SIDs is greatly improved.

The embodiment of the invention adopts the following technical scheme:

in a first aspect, the present invention provides a method for SRv SID allocation in a multi-topology resource-based environment, including:

dividing SID into topology ID and resource ID;

searching corresponding service resources according to the received SID allocation request and allocating the resource IDs;

setting the VTN topology bitmap of the request;

the assigned SID is returned using a combination of Locator + topology ID + resource ID.

Further, the searching for the corresponding service resource and allocating the resource ID according to the received SID allocation request specifically includes:

receiving SID allocation request of a certain VTN topology;

searching an allocation relation table according to a service resource key in the received SID allocation request, and judging whether the service resource corresponding to the VTN topology is allocated with a resource ID or not;

if no resource ID is allocated, a resource ID is allocated to the resource ID, and if the resource ID is already allocated, the resource ID does not need to be reallocated.

Further, the VTN topology bitmap of the set request specifically includes:

and modifying the original topology bitmap according to the SID allocation request of the newly added VTN topology so as to record that the service resources corresponding to the newly added VTN topology are allocated and referenced by the new VTN topology.

Further, the method also comprises a SID release process:

resetting the corresponding VTN topology bitmap, if the topology bitmap in the allocation relation is 0, releasing the SID, otherwise, not releasing the SID.

Further, the SID release procedure specifically includes:

receiving SID release request of a certain VTN topology;

searching an allocation relation table according to the service resource key, and judging whether the service resource corresponding to the VTN topology is allocated with a resource ID or not;

if so, resetting the corresponding VTN topology bitmap, and checking whether the topology bitmap in the allocation relation is 0;

and if the topology bitmap is 0, releasing the SID.

Further, in the SID release process, if the service resources corresponding to the VTN topology are not allocated with the resource ID, the process is directly ended; if the topology bitmap is not 0, the process is directly ended.

Further, the Locator segment of the SID remains fixed as a prefix.

Further, for the same service resource, under different topologies, the resource IDs are the same, and the topology IDs are different.

Further, the topology ID is a VTN ID in a network slice, and the resource ID is an ID based on sub-interface, next hop, VPN instance and EVPN instance resource allocation.

On the other hand, the invention provides a SRv SID allocation device under a multi-topology environment based on resources, which comprises the following specific steps: the method comprises the steps of connecting at least one processor and a memory through a data bus, wherein the memory stores instructions executed by the at least one processor, and the instructions are used for completing the method for SRv SID allocation in the resource-based multi-topology environment in the first aspect after being executed by the processor.

Compared with the prior art, the embodiment of the invention has the beneficial effects that: in VPN+ application deployment, when the VTN corresponding to the multi-network slice distributes SIDs, memory occupation is greatly reduced, and distribution and release efficiency is improved. On the other hand, the invention also solves the problem puzzled in the industry at present, namely the problem of carrying the VTN ID.

[ description of the drawings ]

In order to more clearly illustrate the technical solution of the embodiments of the present invention, the drawings that are required to be used in the embodiments of the present invention will be briefly described below. It is evident that the drawings described below are only some embodiments of the present invention and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 is a diagram of an exemplary SRv6 multi-topology network in the background of the invention;

FIG. 2 is a diagram showing the distribution of SRv SIDs in the prior art;

fig. 3 is a flowchart of a method for SRv SID allocation in a multi-topology environment based on resources according to embodiment 1 of the present invention;

FIG. 4 is a schematic diagram of SID value division provided in embodiment 1 of the present invention;

fig. 5 is a comparative schematic diagram of a SRv SID allocation method provided in embodiment 1 of the present invention;

FIG. 6 is a flowchart showing the steps 200 according to embodiment 1 of the present invention;

FIG. 7 is a flowchart of SID release provided in embodiment 1 of the present invention;

FIG. 8 is a block diagram of a system module for SRv SID assignment in a multi-topology resource-based environment according to embodiment 2 of the present invention;

fig. 9 is a schematic diagram of a device structure for SRv SID allocation in a multi-topology environment based on resources according to embodiment 3 of the present invention.

[ detailed description ] of the invention

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

The present invention is an architecture of a specific functional system, so that in a specific embodiment, functional logic relationships of each structural module are mainly described, and specific software and hardware implementations are not limited.

In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other. The invention will be described in detail below with reference to the drawings and examples.

Example 1:

as shown in fig. 3, the embodiment of the invention provides a method for SRv SID allocation in a multi-topology environment based on resources, which comprises the following specific steps.

Step 100: variable functions+images at SID allocation are divided into topology id+resource ID. That is, this step divides the SID into topology id+resource ID.

Step 200: and searching corresponding service resources according to the received SID allocation request and allocating the resource IDs.

Step 300: the VTN topology bitmap of the request is set.

Step 400: the assigned SID is returned using a combination of Locator + topology ID + resource ID.

In this embodiment, the variable function+structures in SRv SID allocation in multi-topology environment are divided into two parts by the steps described above: the topology ID and the resource ID are used for abstracting the service resources, so that the service resources can be applied to a plurality of different network topologies only by distributing the resource ID once under the condition of the same service resources, thereby greatly improving the distribution efficiency of SRv SIDs.

Specifically, each step in this embodiment will be described in detail below.

First, in SRv network, the common SIDs are of the following types:

1) Node-related: and END.

2) The outgoing interface is next hop dependent: end.x/end.dx4/end.dx6/end.dx2/end.dx2l.

3) Service instance related: end.dt4/end.dt6/end.dt2u/end.dt2m.

When the SIDs are allocated to the Locator segments corresponding to different VTNs, if the SIDs correspond to the same service resource: for example, the end.x is allocated to the same subinterface resource or the end.dt4 is allocated to the same vpn resource, and the corresponding service resource is one when allocated, but the allocation is performed in different Locator segments.

As shown in fig. 4, the present patent divides the variable function+structures at SID assignment into two parts: topology ID (in the figure), resource ID (in the figure), and Locator is fixed as a prefix with respect to the subsequent fields.

Topology ID: in network slices, the VTN ID is typically the same. Through the design of the topology ID, the invention solves the problem of carrying the VTN ID in the prior art.

Resource ID: based on the ID of the resource allocation like subinterface, next hop, VPN instance, EVPN instance, etc.

In the prior art, the SID is originally allocated through variable function+domains, so that when different Locator segments are allocated, the existing allocation method needs to maintain allocation relations (SID < - - > service resources in the background art) respectively, thereby occupying more resources and memory and having lower efficiency.

For the technical scheme, for the same service resource, the resource IDs are the same under different topologies, and only the topology IDs are different. Therefore, the field behind the Locator section is divided into the topology ID and the resource ID when the SID is allocated, so that the aim of quickly applying the topology to another VTN topology by only allocating the resource ID for the same service resource once is fulfilled.

After the SRv SID allocation method is adopted, as shown in fig. 5, two SIDs on the left side of fig. 5 are allocated in the allocation manner in the prior art, and the SID allocation manner on the right side is the allocation manner of the embodiment. Each row of text under the box in fig. 5 represents one resource allocated in the allocated area, and for the allocation manner in the prior art, as for the background art, it is required to maintain respective allocation relationships (SID < - - > service resources), but in the allocation manner in this embodiment, for the SIDs of the plurality of Locator segments, only one allocation relationship needs to be maintained: resource ID (resource ID) +topology bitmap+traffic resources.

The topology bitmap in the above allocation relationship refers to that if the same service resource is allocated and used by multiple topologies, the topology bitmap records all managed topologies. For example, topology 1 and topology 2 have the same traffic resource vpn1, and then topology bitmap can express this information using binary 11. For example, topology 1 has no traffic resource vpn2, and topology 2 has traffic resource vpn2, then 01 can be used to express this information. Similarly, if there is a traffic resource in topology 1 and there is no traffic resource in topology 2, it can be represented by 10. It should be noted that, in this embodiment, the bit number of the bitmap is variable, and generally, when implementing, an integer size has 32 bits, which can represent 32 topology IDs, and depending on the number of topologies, for example, only two topologies are needed, which is represented by 0 and 1 of two bits (0 represents that the topology has no corresponding service resource, and 1 represents that the topology has a corresponding service resource), and how many topologies are represented by 0 and 1 of how many bits, and when the number of topologies exceeds 32, variable length expansion of the similar array can be performed.

Based on the above description, it is obvious that in the new SRv SID allocation method, in a multi-topology environment, on one hand, the SRv SID allocation efficiency can be greatly improved, and on the other hand, the occupation of allocation resources can be reduced.

On the basis of the topology ID and resource ID division in step 100, the corresponding SID allocation procedure may be represented as steps 200-400, which are specifically described below.

As shown in fig. 6, in the present preferred embodiment, step 200 (searching for a corresponding service resource and allocating a resource ID according to the received SID allocation request) specifically includes:

step 201: a SID assignment request for a certain VTN topology is received.

Step 202: and searching an allocation relation table according to the service resource key in the received SID allocation request, and judging whether the service resource corresponding to the VTN topology is allocated with a resource ID. In the above allocation relation: for example, the resource ID) +topology bitmap+service resource, this step finds the corresponding allocation relationship through the key value of the service resource, and then determines whether the service resource corresponding to the VTN topology that receives the SID allocation request has allocated the resource ID.

Step 203: if no resource ID is allocated, a resource ID is allocated to the resource ID, and if the resource ID is already allocated, the resource ID does not need to be reallocated.

In the preferred embodiment, step 300 (set the VTN topology bitmap of the request) specifically includes: and modifying the original topology bitmap according to the SID allocation request of the newly added VTN topology so as to record that the service resources corresponding to the newly added VTN topology are allocated and referenced by the new VTN topology. The topology bitmap records the corresponding relation between a service resource and a plurality of topologies, which means that the service resource is referenced by all VTN topologies represented by the bitmap, and setting the VTN topology bitmap means that new VTNs are newly added to record the topology bitmap corresponding to the service resource to reference the service resource.

Specifically, for example, there are three

topologies

1, 2 and 3, and at the beginning, only

topology

1 and 2 have corresponding resource allocation SID, at this time, topology bitmap expresses it as binary 011, and now also needs to be configured with SID in topology 3, after setting, the corresponding topology bitmap expression is binary 111, and the binary expression records that the service resource is allocated and referenced by the new VTN topology.

Finally, step 400 is performed: the assigned SID is returned using a combination of Locator + topology ID + resource ID. It should be noted that, the final returned SID is also in a standard SID format, which is the format of an IPv6 address, and the SID of the IPv 6-like address is formed by combining a locator+topology id+resource ID.

In the present preferred embodiment, in addition to the SID allocation procedure described above, the SID release procedure is included: resetting the corresponding VTN topology bitmap, if the topology bitmap in the allocation relation is 0, releasing the SID, otherwise, not releasing the SID.

Specifically, as shown in fig. 7, the SID release procedure specifically includes:

step 501: a SID release request for a certain VTN topology is received.

Step 502: and searching an allocation relation table according to the service resource key, and judging whether the service resource corresponding to the VTN topology is allocated with a resource ID. This step is an optional step, and in general, even if only one topology is used, the resource ID will be allocated first, so that the topology will be known to have been allocated with the resource ID without judgment, but in order to prevent system errors, the SID is released more tightly, and this step can be reserved, so that judgment is more strict.

Step 503: if so, resetting the corresponding VTN topology bitmap, and checking whether the topology bitmap in the allocation relation is 0; if not, directly ending the release process. It should be noted that resetting the VTN topology bitmap here means that, for the topology bitmap corresponding to the service resource, the reference relationship between the VTN topology and the service resource is released.

Step 504: under the condition that the resource ID is allocated, if the topology bitmap is 0, releasing the SID; if the topology bitmap is not 0, the release process is directly ended. The assignment and release of SIDs are manifested as an increase and decrease in topology, respectively.

Obviously, under the above design, compared with the prior art, the SID release process in this embodiment has the beneficial effects of reducing memory occupation and improving release efficiency.

As can be seen from the above description of the present embodiment, compared with the prior art, in the vpn+application deployment, when the SID is allocated to the VTN corresponding to the multiple network slices, the memory occupation is greatly reduced, and the allocation and release efficiency is improved. On the other hand, the invention also solves the problem puzzled in the industry at present, namely the problem of carrying the VTN ID.

Example 2:

based on the method for SRv SID allocation in the multi-topology resource-based environment provided in embodiment 1, embodiment 2 provides a system for SRv SID allocation in the multi-topology resource-based environment corresponding to embodiment 1, as shown in fig. 8, where the system includes a SID value dividing module, a resource ID allocating module, a set topology bitmap module, a SID allocating module, and a SID releasing module. The SID value dividing module is used for dividing variable functions and images during SID allocation into topology IDs and resource IDs; the resource ID allocation module is used for searching corresponding service resources according to the received SID allocation request and allocating the resource IDs; the setting topology bitmap module is used for setting the VTN topology bitmap of the request; the SID allocation module is used for returning the allocated SID by using the combination of the Locator + topology ID + resource ID; the SID release module is used for executing SID release request of the VTN topology.

Corresponding to embodiment 1, the SID value dividing module of this embodiment 2 is responsible for the function corresponding to step 100 in embodiment 1; the function for which the resource ID allocation module is responsible corresponds to step 200 in embodiment 1; the function for setting the topology bitmap module to be responsible corresponds to step 300 in embodiment 1; the function for which the SID assignment module is responsible corresponds to step 400 in embodiment 1; the function for which the SID release module is responsible corresponds to the SID release procedure in embodiment 1.

Specifically, the resource ID allocation module may be further subdivided into the following: the device comprises an allocation request acquisition module, a resource ID judgment module and a resource ID allocation module. The distribution request acquisition module is used for receiving SID distribution requests of the VTN topology; the resource ID judging module is used for searching an allocation relation table according to the service resource key and judging whether the service resource corresponding to the VTN topology is allocated with a resource ID or not; the resource ID allocation module is used for allocating a resource ID to the service resource when the service resource is not allocated with the resource ID.

The SID release module can also be subdivided into the following: the device comprises a release request acquisition module, a resource ID judgment module, a topology bitmap inspection module and a release SID module. The release request acquisition module is used for acquiring SID release requests of the VTN topology; the resource ID judging module is used for searching an allocation relation table according to the service resource key and judging whether the service resource corresponding to the VTN topology is allocated with a resource ID or not; the topology bitmap checking module is used for resetting the corresponding VTN topology bitmap under the condition of allocated resource ID, and checking whether the topology bitmap in the allocation relation is 0; the releasing SID module is used for releasing SID under the condition that the topology bitmap is 0.

In this embodiment, the above modules are cooperatively processed to realize allocation and release of SRv SID in a multi-topology environment, so as to achieve the technical effects of greatly reducing memory occupation and improving allocation and release efficiency. The flow and steps of the cooperative processing between the modules in this embodiment are detailed in embodiment 1, and are not described herein.

Example 3:

on the basis of the method and system for SRv SID allocation in the multi-topology resource-based environment provided in the foregoing embodiments 1 to 2, the present invention further provides a device for SRv SID allocation in the multi-topology resource-based environment, which can be used to implement the method and system, as shown in fig. 9, and is a schematic device architecture of an embodiment of the present invention. The apparatus for SRv SID allocation in a resource-based multi-topology environment of this embodiment includes one or more processors 21 and memory 22. In fig. 9, a processor 21 is taken as an example.

The processor 21 and the memory 22 may be connected by a bus or otherwise, which is illustrated in fig. 9 as a bus connection.

The memory 22 is used as a non-volatile computer readable storage medium for storing non-volatile software programs, non-volatile computer executable programs, and modules, such as the method and system for SRv SID assignment in the resource-based multi-topology environment of embodiments 1-2. The processor 21 executes various functional applications and data processing of the apparatus for SRv SID allocation in the resource-based multi-topology environment, that is, implements the method and system for SRv SID allocation in the resource-based multi-topology environment of embodiments 1 to 2, by running the nonvolatile software programs, instructions, and modules stored in the memory 22.

The memory 22 may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, memory 22 may optionally include memory located remotely from processor 21, which may be connected to processor 21 via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

Program instructions/modules are stored in the memory 22 that, when executed by the one or more processors 21, perform the methods, systems, and methods of SRv SID assignment in a resource-based multi-topology environment in embodiments 1-2 described above, e.g., performing the various steps/module functions illustrated in fig. 1-8 described above.

Those of ordinary skill in the art will appreciate that all or a portion of the steps in the various methods of the embodiments may be implemented by a program that instructs associated hardware, the program may be stored on a computer readable storage medium, the storage medium may include: read Only Memory (ROM), random Access Memory (RAM), magnetic disk or optical disk.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. A method for SRv SID allocation in a multi-topology resource-based environment, comprising:

setting the VTN topology bitmap of the request; the method specifically comprises the following steps: modifying an original topology bitmap according to SID allocation request of the newly added VTN topology to record that service resources corresponding to the newly added VTN topology are referenced by the new VTN topology allocation, wherein the topology bitmap records the corresponding relation between one service resource and a plurality of topologies, which means that the service resource is referenced by all VTN topologies represented by the bitmap;

returning the allocated SID by using a combination of a locator+topology ID+resource ID;

wherein, the variable function+domains in the allocation of SRv SID in the multi-topology environment are re-divided into two parts: the topology ID and the resource ID abstract the service resources, so that the service resources can be applied to a plurality of different network topologies only by distributing the resource ID once under the condition of the same service resources.

2. The method for SRv SID allocation in a multi-topology resource-based environment according to claim 1, wherein said searching for the corresponding service resource and allocating the resource ID according to the received SID allocation request specifically comprises:

receiving SID allocation request of a certain VTN topology;

3. The method of SRv SID assignment in a resource-based multi-topology environment of claim 1, further comprising a SID release procedure:

4. The method for SRv SID assignment in a multi-topology resource-based environment of claim 3, wherein said SID release procedure specifically comprises:

receiving SID release request of a certain VTN topology;

and if the topology bitmap is 0, releasing the SID.

5. The method for SRv SID assignment in a multi-topology resource-based environment according to claim 4, wherein in the SID release procedure, if the service resources corresponding to the VTN topology are not assigned with the resource ID, directly ending the procedure; if the topology bitmap is not 0, the process is directly ended.

6. The method of SRv SID assignment in a multi-topology resource based environment according to any one of claims 1-5, wherein the Locator segment of said SID remains fixed as a prefix.

7. The method of SRv SID assignment in a multi-topology resource-based environment according to any one of claims 1-5, wherein said topology ID is VTNID in a network slice and said resource ID is an ID based on subinterface, next hop, VPN instance, EVPN instance resource assignment.

8. An apparatus for SRv SID allocation in a multi-topology resource-based environment, comprising:

comprising at least one processor and a memory connected by a data bus, the memory storing instructions for execution by the at least one processor, the instructions, when executed by the processor, for performing the method of SRv SID allocation in a resource-based multi-topology environment according to any one of claims 1-7.