CN116781618A

CN116781618A - Route generation method, data message forwarding method and device

Info

Publication number: CN116781618A
Application number: CN202210459509.7A
Authority: CN
Inventors: 庞东磊; 王海波
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-03-11
Filing date: 2022-04-27
Publication date: 2023-09-19

Abstract

The application provides a route generation method, a data message forwarding method and a data message forwarding device, and belongs to the technical field of communication. The object of the routing calculation is the address information corresponding to the first protocol stack, and the result of the routing calculation comprises the address information corresponding to the second protocol stack, namely, the object of the routing calculation and the result of the routing calculation are allowed to have different address family types. In this way, a method of supporting dual stack hybrid route computation is achieved. Compared with the single-stack route calculation mode in the prior art, the method can support the requirement of dual-stack service by configuring one address of the IPv4 address or the IPv6 address on the interface corresponding to the link without configuring the addresses of two protocol stacks, thereby saving IP address resources.

Description

Route generation method, data message forwarding method and device

The application claims priority from chinese patent application No. 202210239542.9, entitled "a BGP SPF method for supporting V6 and V4 dual stack hybrid route calculation," filed on 11, 2022, incorporated herein by reference in its entirety.

Technical Field

The present application relates to the field of communications technologies, and in particular, to a route generating method, a data packet forwarding method and a device.

Background

Currently, various routing protocols generally adopt a single-stack routing calculation mode. That is, in the route calculated by the network device for an internet protocol version 4 (internet protocol version, IPv 4) prefix, the outgoing interface is an interface configured with an IPv4 address of the network device itself, and the next hop is an IPv4 address configured by an interface of the peer network device; in the route calculated by the network device for an internet protocol version 6 (internet protocol version, IPv 6) prefix, the outgoing interface is an interface of the network device itself configured with an IPv6 address, and the next hop is an IPv6 address configured by an interface of the peer network device. That is, the types of the protocol stacks (or address families) corresponding to the prefix, the next hop and the outgoing interface are the same, and are either IPv4 or IPv6. From the perspective of the routing table and forwarding table descriptions on the network device, the address family type of the prefix and the address family type of the next hop are consistent in the same table entry of the routing table or forwarding table.

However, if the above-mentioned single-stack route calculation method is adopted to implement the dual-stack service, two addresses, that is, an IPv4 address and an IPv6 address, need to be configured on the interface corresponding to each link, which results in a need to consume a large amount of address resources.

Disclosure of Invention

The embodiment of the application provides a route generation method, a data message forwarding method and a device, which are beneficial to saving address resources. The technical scheme is as follows.

In a first aspect, a route generation method is provided, the method including:

the first network device obtains a network topology;

the first network equipment receives a route notification message from the second network equipment, wherein the route notification message is used for issuing address information corresponding to a first protocol stack;

the first network device generates a route including the address information corresponding to the first protocol stack and address information corresponding to a second protocol stack, the address information corresponding to the second protocol stack being address information of an endpoint network device of a first link in the network topology.

In the above method, the object of the routing calculation is address information corresponding to the first protocol stack, and the result of the routing calculation includes address information corresponding to the second protocol stack, that is, the object of the routing calculation is allowed to have a different address family type from the result of the routing calculation. In this way, a method of supporting dual stack hybrid route computation is achieved. Compared with the single-stack route calculation mode in the prior art, the method can support the requirement of dual-stack service by configuring the address information of one protocol stack on the interface corresponding to the link without configuring the addresses of two protocol stacks, thereby saving the address resources of internet protocol (internet protocol, IP).

In some embodiments, the address information of the endpoint network devices of all links other than the first link in the network topology is address information corresponding to a second protocol stack.

By the mode, the method is beneficial to supporting the single-stack topology to perform double-stack mixed route calculation under the scene that all links in the network are deployed based on the second protocol stack.

In some embodiments, the network topology further includes a second link, an endpoint network device of the second link including address information corresponding to the first protocol stack.

By the method, the dual-stack hybrid route calculation is supported under the scene that links corresponding to different protocol stacks exist between different network devices.

In some embodiments, the network topology includes a dual stack link, an endpoint network device of which includes address information corresponding to a first protocol stack and address information corresponding to a second protocol stack.

By the method, the dual-stack mixed route calculation is supported in the scene of dual-stack link deployment.

In some implementations, the second network device belongs to a border gateway protocol shortest path first computing (shortest path first with border gateway protocol, BGP SPF) routing domain and to an interior gateway protocol (interior gateway protocol, IGP) routing domain, and the address information corresponding to the first protocol stack is address information of a third network device in the IGP routing domain.

By the mode, the method is beneficial to supporting the introduction of the address information of the network equipment in the IGP routing domain into the BGP SPF routing domain in the scene that the BGP SPF routing domain and the IGP routing domain are spliced to form the basic network.

In some embodiments, the address information corresponding to the first protocol stack is address information of a user equipment to which the second network device accesses.

In some embodiments, the first network device obtains a network topology, comprising:

the first network equipment receives a link notification message, wherein the link notification message is used for issuing address information of endpoint network equipment of the first link;

the first network device obtains the network topology according to address information of endpoint network devices of the first link.

In some embodiments, the route advertisement message is a BGP SPF message.

In some embodiments, the first protocol stack is an IPv4 protocol stack and the second protocol stack is an IPv6 protocol stack; or alternatively, the process may be performed,

the first protocol stack is an IPv6 protocol stack, and the second protocol stack is an IPv4 protocol stack.

In a second aspect, a method for forwarding a data packet is provided, in which method,

the method comprises the steps that first network equipment receives a data message, wherein the data message comprises address information corresponding to a first protocol stack;

The first network device forwards the data message to the address information corresponding to the second protocol stack based on the address information corresponding to the first protocol stack and a route including the address information corresponding to the first protocol stack and the address information corresponding to the second protocol stack.

In the method, after receiving the data message containing the address information of the first protocol stack, the data message is forwarded to the address information corresponding to the second protocol stack by utilizing the route containing the address information of the two protocol stacks, thereby supporting the requirement of dual-stack service, and the addresses of the two protocol stacks are not required to be configured on the interface corresponding to the link, so that IP address resources are saved.

In a third aspect, a route generation device is provided, which has the functionality to implement the above-mentioned first aspect or any of the alternatives of the first aspect. The route generating device comprises at least one unit for implementing the method provided in the first aspect or any of the alternatives of the first aspect.

In some embodiments, the units in the route generation device are implemented in software, and the units in the route generation device are program modules. In other embodiments, the units in the route generation device are implemented in hardware or firmware. The specific details of the route generating device provided in the third aspect may be referred to the above first aspect or any optional manner of the first aspect, which is not described herein.

In a fourth aspect, a forwarding device for a data packet is provided, where the forwarding device for a data packet has a function of implementing the second aspect or any of the optional modes of the second aspect. The forwarding device of the data message comprises at least one unit, and the at least one unit is configured to implement the method provided in the second aspect or any optional manner of the second aspect.

In some embodiments, the units in the forwarding device of the data packet are implemented in software, and the units in the forwarding device of the data packet are program modules. In other embodiments, the units in the forwarding device of the data packet are implemented in hardware or firmware. The details of the forwarding device for data packets provided in the fourth aspect may be found in the second aspect or any of the optional manners of the second aspect, which are not described herein.

In a fifth aspect, there is provided a network device comprising a processor for executing instructions to cause the network device to perform the method provided in the first aspect or any of the alternatives of the first aspect, and a network interface for receiving or sending messages. The specific details of the network device provided in the fifth aspect may be referred to the above first aspect or any optional manner of the first aspect, which is not described herein.

In a sixth aspect, there is provided a network device comprising a processor and a network interface, the processor being configured to execute instructions to cause the network device to perform the method provided in the second aspect or any of the alternatives of the second aspect, the network interface being configured to receive or transmit a message. The details of the network device provided in the sixth aspect may be found in the second aspect or any optional manner of the second aspect, which is not described herein.

In a seventh aspect, there is provided a computer readable storage medium having stored therein at least one instruction that when executed on a processor causes the processor to perform the method provided in the first aspect or any of the alternatives of the first aspect.

In an eighth aspect, there is provided a computer readable storage medium having stored therein at least one instruction that when executed on a processor causes the processor to perform the method provided in the second aspect or any of the alternatives of the second aspect.

In a ninth aspect, there is provided a computer program product comprising one or more computer program instructions which, when loaded and run by a computer, cause the computer to carry out the method as provided in the first aspect or any of the alternatives of the first aspect.

In a tenth aspect, there is provided a computer program product comprising one or more computer program instructions which, when loaded and run by a computer, cause the computer to carry out the method as provided in the second aspect or any of the alternatives of the second aspect described above.

In an eleventh aspect, a chip is provided, comprising a memory for storing computer instructions and a processor for calling and executing the computer instructions from the memory for performing the method of the first aspect and any possible implementation of the first aspect.

In a twelfth aspect, there is provided a chip comprising a memory for storing computer instructions and a processor for calling and executing the computer instructions from the memory to perform the method provided in the second aspect or any of the alternatives of the second aspect.

In a thirteenth aspect, there is provided a network device comprising: the main control board and the interface board further comprise a switching network board. The network device is configured to perform the method of the first aspect or any possible implementation of the first aspect. In particular, the network device comprises means for performing the method of the first aspect or any possible implementation of the first aspect.

In a fourteenth aspect, there is provided a network device comprising: the main control board and the interface board further comprise a switching network board. The network device is configured to perform the method of the second aspect or any possible implementation of the second aspect. In particular, the network device comprises means for performing the method of the second aspect or any possible implementation of the second aspect.

Drawings

Fig. 1 is a schematic diagram of a network deployment scenario provided in an embodiment of the present application;

Fig. 2 is a flowchart of a route generation method according to an embodiment of the present application;

fig. 3 is a schematic format diagram of a BGP SPF prefix NLRI according to an embodiment of the present application;

fig. 4 is a schematic diagram of a format of a prefix descriptor field in a BGP SPF prefix NLRI according to an embodiment of the present application;

fig. 5 is a schematic diagram of a format of a BGP SPF link NLRI according to an embodiment of the present application;

fig. 6 is a schematic diagram of a format of a BGP SPF node NLRI according to an embodiment of the present application;

fig. 7 is a schematic view of a scenario in which BGP SPF routing domains and IGP routing domains are spliced and deployed according to an embodiment of the present application;

fig. 8 is a schematic diagram of a scenario in which another BGP SPF routing domain provided by an embodiment of the present application is spliced and deployed with an IGP routing domain;

fig. 9 is a schematic diagram of a scenario in which another BGP SPF routing domain and an IGP routing domain are spliced and deployed according to an embodiment of the present application;

fig. 10 is a schematic diagram of a scenario in which another BGP SPF routing domain provided by an embodiment of the present application is spliced and deployed with an IGP routing domain;

fig. 11 is a schematic diagram of a scenario in which a BGP SPF routing domain is deployed for a dual-stack link according to an embodiment of the present application;

FIG. 12 is a schematic diagram of an IPv4 topology provided by an embodiment of the present application;

FIG. 13 is a schematic diagram of an IPv6 topology provided by an embodiment of the present application;

FIG. 14 is a schematic diagram of a hybrid dual stack topology provided by an embodiment of the present application;

fig. 15 is a schematic view of a scenario in which BGP SPF routing domains are deployed for splicing an IPv4 link and an IPv6 link according to an embodiment of the present application;

fig. 16 is a schematic structural diagram of a route generating device 600 according to an embodiment of the present application;

fig. 17 is a schematic structural diagram of a forwarding device 700 for data packets according to an embodiment of the present application;

fig. 18 is a schematic structural diagram of a network device 800 according to an embodiment of the present application;

fig. 19 is a schematic structural diagram of a network device 900 according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in further detail with reference to the accompanying drawings.

The following describes a network deployment scenario provided by an embodiment of the present application.

Fig. 1 is a schematic diagram of a network deployment scenario provided in an embodiment of the present application. The scenario illustrated in fig. 1 includes network device D, network device C, network device E, network device F, and Customer Edge (CE).

Any of network device D, network device C, network device E, and network device F includes, but is not limited to, a router, a switch, and the like. Network device D, network device C, network device E and network device F belong to one routing domain. Routing domains, autonomous systems, in one routing domain a group of routers exchange routing information via the same routing protocol.

The scenario shown in fig. 1 is a scenario based on an IPv6 network deployment. Network device D is connected to network device E via an IPv6 link. Network device C is connected to network device F via an IPv6 link. In addition, both the network device E and the network device F are connected to the CE.

As shown in fig. 1, the network device D has an interface 3, the interface 3 being configured with an IPv6 address 10:20. The network device E has an interface 4, the interface 4 being configured with an IPv6 address 10:10. An IPv6 link is established between interface 3 and interface 4. That is, for an IPv6 link between network device D and network device E, the end point network device of the IPv6 link includes network device D and network device E, and the information of the IPv6 link includes IPv6 address 10::20 and IPv6 address 10::10.

The network device C has an interface 6, the interface 6 being configured with an IPv6 address 30::20. The network device F has an interface 5, the interface 5 being configured with an IPv6 address 30:10. An IPv6 link is established between interface 6 and interface 5. That is, for an IPv6 link between network device C and network device F, the end point network device for this IPv6 link includes network device C and network device F, and the information for this IPv6 link includes IPv6 address 30::20 and IPv6 address 30::10.

The inventor of the present application found that the conventional technology based on single-stack topology routing computation has a plurality of defects when implementing dual-stack service.

By dual stack, it is meant two sets of protocol stacks, e.g., IPv4 and IPv 6. The dual stack service refers to that a network device can forward data packets corresponding to two protocol stacks. In many scenarios, there is a need to implement dual stack services. Taking two protocol stacks as an IPv4 protocol stack and an IPv6 protocol stack as an example, in an exemplary scenario, when an operator upgrades a basic (underlay) network from an IPv4 network to an IPv6 network, a transition process is generally required, that is, there is both an IPv 4-capable network device and an IPv4 link and an IPv 6-capable network device and an IPv6 link in the underlay network. In another exemplary scenario, there is also a case where a terminal device that installs an application has both an IPv4 address and an IPv6 address for a long period of time, in the process of an application's gradual upgrade from IPv 4-based communication to IPv 6-based communication. In these two scenarios, it relates to coexistence and interworking between an IPv4 network and an IPv6 network, where network devices are required to be able to forward data packets to either an IPv6 network device or an IPv6 terminal, or to forward data packets to either an IPv4 network device or an IPv4 terminal.

In the conventional technology, when implementing the dual-stack service, all links need to be configured as dual-stack links, so as to form dual-stack physical topologies, namely an IPv4 network topology and an IPv6 network topology. For an IPv4 prefix, the network device calculates a route based on the IPv4 network topology. For an IPv6 prefix, the network device calculates a route based on the IPv6 network topology.

However, this approach consumes a significant amount of internet protocol (internet protocol, IP) address resources. Specifically, when each link in the network is configured as a dual stack link, a pair of IPv4 addresses and a pair of IPv6 addresses need to be configured, for example, configuring one link between interface 1 of device a and interface 2 of device B as a dual stack link requires that IPv4 addresses and IPv6 addresses be configured on interface 1, and that IPv4 addresses and IPv6 addresses also be configured on interface 2. Then, the device A establishes a link based on the IPv4 address of the interface 1 and the device B establishes a link based on the IPv4 address of the interface 2; device a establishes a link based on the IPv6 address of interface 1 and device B establishes a link based on the IPv6 address of interface 2. As traffic progresses, networks grow larger in size, and a large number of IP addresses are certainly required. In addition, each network device needs to deploy two sets of protocol stacks of IPv4 and IPv6 protocols to support dual stack service, so that deployment and maintenance are complex, and the processing pressure of the network device is high.

Based on this, some embodiments of the application provide a way to support dual stack hybrid route computation. Taking two protocol stacks as an IPv4 protocol stack and an IPv6 protocol stack as examples, for example, optionally, in a route calculated by the network device for an IPv4 prefix, an outgoing interface is an interface configured with an IPv6 address of the network device itself, and a next hop is an IPv6 address configured by an interface of the peer network device; as another example, in the route calculated by the network device for an IPv6 prefix, the outgoing interface is an interface configured with an IPv4 address of the network device itself, and the next hop is an IPv4 address configured by an interface of the peer network device. That is, the types of the IP protocol stacks corresponding to the prefix, the next hop and the outgoing interface are inconsistent. From the perspective of the routing table and forwarding table descriptions on the network device, the address family type of the prefix and the address family type of the next hop are different in the same table entry of the routing table or forwarding table. For example, the prefix is an IPv4 prefix and the next hop is an IPv6 address, or the prefix is an IPv6 prefix and the next hop is an IPv4 address.

In this way, the route is calculated, and the two protocol stacks are respectively described as an IPv4 protocol stack and an IPv6 protocol stack, and in the data plane forwarding stage, when the network device receives an IPv4 data packet, the network device can address to an IPv6 next hop when searching for the route based on a destination IPv4 address in the IPv4 data packet, and forward the IPv4 data packet to the IPv6 next hop through an configured egress interface of the IPv6 address, without using an IPv4 address local to the network device, and basically without requiring the network device to establish a link with an opposite-end network device and maintain communication based on the IPv4 protocol. Therefore, the method reduces the number of the IP addresses required to be configured by the network equipment for supporting the dual-stack service, and saves the IP address resources. And moreover, the workload of deployment and maintenance caused by maintaining two sets of IP protocol stacks is reduced, and the cost of network equipment is reduced.

Fig. 2 is a flowchart of a route generating method according to an embodiment of the present application. The method shown in fig. 2 includes the following S201 to S204.

The method shown in fig. 2 involves interactions between a plurality of network devices. To distinguish between different network devices, a plurality of different network devices are described with a "first network device", "second network device" distinction.

The method shown in fig. 2 involves dual protocol stack hybrid routing computation, and in order to distinguish between different protocol stacks, a plurality of different protocol stacks are described with "first protocol stack", "second protocol stack" distinction. For example, the first protocol stack is an IPv4 protocol stack, and the second protocol stack is an IPv6 protocol stack. For another example, the first protocol stack is an IPv6 protocol stack, and the second protocol stack is an IPv4 protocol stack. It should be understood that the present application is not limited to the type of the protocol stack, and hereinafter, the description will be given taking the first protocol stack as an IPv4 protocol stack and the second protocol stack as an IPv6 protocol stack as an example.

The network deployment scenario on which the method of fig. 2 is based is optionally as described above with respect to fig. 1. For example, as seen in connection with fig. 1, the first network device in the method shown in fig. 2 is network device D in fig. 1, and the second network device in the method shown in fig. 2 is network device E in fig. 1.

S201, the first network device obtains a network topology.

The network topology is used to indicate network devices and links present in the routing domain. In some embodiments, the network topology includes address information of endpoint network devices of at least one link. Optionally, the network topology further comprises an identification of endpoint network devices of the at least one link. The first network device generates a route based on some or all of the information in the network topology by obtaining the network topology.

The above network topology is illustrated below in connection with different network deployment scenarios, see scenario one through scenario four below.

Scene one, pure IPv6 base network deployment scene

In the scene, all links in the network topology are IPv6 links. In other words, the address information of the endpoint network devices of all links in the network topology is an IPv6 address.

For example, network device a and network device B are deployed in a network. The interface a of the network device a is configured with an IPv6 address a, and the interface B of the network device B is configured with an IPv6 address B. Network device a establishes a link 1 based on IPv6 address a and network device B establishes a link based on IPv6 address B. In this example, link 1 is an IPv6 link, and the end point network devices of link 1 include network device a and network device B. The address information of the endpoint network devices of link 1 includes IPv6 address a and IPv6 address B. Similarly, each link in the network except for link 1 is an IPv6 link, which corresponds to a pure IPv6 network.

Scene two, pure IPv4 base network deployment scene

In scenario two, the address information of the endpoint network devices of all links in the network topology is an IPv4 address. In other words, all links in the network topology are IPv4 links.

For example, network device a and network device B are deployed in a network. The interface a of the network device a is configured with an IPv4 address a, and the interface B of the network device B is configured with an IPv4 address B. Network device a establishes a link 1 based on IPv4 address a and network device B establishes a link based on IPv4 address B. In this example, link 1 is an IPv4 link, and the end point network devices of link 1 include network device a and network device B. The address information of the endpoint network devices of link 1 includes IPv4 address a and IPv4 address B. Similarly, each link in the network except for link 1 is an IPv4 link, which corresponds to a pure IPv4 network.

Scene three, IPv6 link and IPv4 link splicing deployment scene

In scenario three, links between different network devices have different address family types, some of which correspond to a first protocol stack and some of which correspond to a second protocol stack.

For example, network device a, network device B, and network device C are deployed in the network. The interface a of the network device a is configured with an IPv6 address a, the interface B1 of the network device B is configured with an IPv6 address B1, and the interface B2 of the network device B is configured with an IPv4 address B2. The interface C of the network device C is configured with an IPv4 address C. Network device a establishes a link 1 based on IPv6 address a and network device B establishes a link based on IPv6 address B1. Network device B establishes a link 2 based on IPv4 address B2 and network device C based on IPv4 address C. In this example, link 1 is an IPv4 link, and the end point network devices of link 1 include network device a and network device B. The address information of the endpoint network devices of link 1 includes IPv4 address a and IPv4 address B. In this example, link 1 is an IPv6 link, and the end point network devices of link 1 include network device a and network device B. The address information of the endpoint network devices of link 1 includes IPv6 address a and IPv6 address B1. Link 2 is an IPv4 link and the end point network devices of link 2 include network device B and network device C. The address information of the endpoint network devices of link 2 is included in IPv4 address B2 and IPv4 address C.

Scene four, dual stack link deployment scene

In scenario four, the network topology includes a dual stack link, and an endpoint network device of the dual stack link includes address information corresponding to a first protocol stack and address information corresponding to a second protocol stack.

S202, the second network equipment generates a route notification message based on address information to be issued, and the second network equipment sends the route notification message to the first network equipment.

There are various possible situations for the address information to be issued. From the viewpoint of the form of the address information, the address information optionally includes at least one of a prefix or an IP address. From the viewpoint of the address family type, the above-mentioned address information is optionally IPv4 address information, for example, the above-mentioned address information includes at least one of an IPv4 prefix or an IPv4 address. Alternatively, the address information is IPv6 address information, and for example, the address information includes at least one of an IPv6 prefix or an IPv6 address.

The apparatus to which the above address information belongs includes various cases, and is exemplified below in conjunction with three cases.

In case one, the address information is address information of the user equipment.

In one exemplary scenario, the second network device has access to a user device, which transmits address information of the user device to the second network device. The second network equipment receives the address information of the user equipment, takes the address information of the user equipment as the address information to be issued, carries the address information in a route notification message, and sends the route notification message to the first network equipment, so that the first network equipment is triggered to calculate the route reaching the user equipment, and the service requirement of forwarding the data message to the user equipment is met. The user equipment is for example a CE, and for example a terminal.

In the second case, the address information is address information configured on one interface of the second network device, that is, address information of the local end of the second network device.

In case three, the address information is address information of a third network device.

For example, the third network device and the second network device belong to a first routing domain, and the second network device and the first network device belong to a second routing domain. The third network device transmits address information of the third network device to the second network device. The second network device receives the address information from the third network device, takes the address information of the third network device as the address information to be issued, carries the address information in a route notification message, and sends the route notification message to the first network device. In this way, the address information of the network equipment in one routing domain is introduced into the other routing domain, so that the requirement of mutual introduction of the address information between different routing domains is met. Optionally, the first routing domain is an IGP routing domain, and the second routing domain is a BGP SPF routing domain. Alternatively, the first routing domain is a BGP SPF routing domain, and the second routing domain is an IGP routing domain.

The route announcement message is used for publishing address information corresponding to the first protocol stack. In some embodiments, the route advertisement message includes an identification of the second network device and address information corresponding to the first protocol stack. For example, referring to fig. 1, the address information to be issued is the IPv4 address 10.1.1.2 of the CE. The network device E (second network device) generates a route advertisement message based on the IPv4 address 10.1.1.2 and the identity of the network device E. The network device E sends a route advertisement message to the network device D through the IPv6 link.

From a protocol type perspective, the route advertisement messages are optionally BGP SPF messages. Alternatively, the route advertisement message is an IGP message. For example, the route advertisement message IS an open shortest path first (open shortest path first, OSPF) message or an intermediate system-to-intermediate system (intermediate system to intermediate system, IS-IS) protocol message. The format and content of the route announcement message are illustrated below by taking the route announcement message as a BGP SPF message as an example.

Optionally, the route advertisement message includes BGP SPF prefix network layer reachability messages (network layer reachability information, NLRI). For example, referring to fig. 3, the second network device sends the BGP SPF prefix NLRI shown in fig. 3 to the first network device, where the local node descriptor field includes an identification of the second network device and the prefix descriptor field includes a prefix corresponding to the first protocol stack.

S203, the first network device receives the route notification message from the second network device.

Optionally, the second network device sends the route announcement message to the first network device through an outbound interface configured with address information of the second protocol stack. The first network device receives the route announcement message through an outbound interface configured with address information of the second protocol stack. For example, the second network device sends a route advertisement message containing an IPv4 prefix to the first network device via an IPv6 interface. The first network device receives a route announcement message containing an IPv4 prefix through an IPv6 interface. For another example, the second network device sends a route advertisement message containing an IPv6 prefix to the first network device via an IPv4 interface. The first network device receives a route announcement message containing an IPv6 prefix through an IPv4 interface.

S204, the first network device generates a route.

The route includes address information corresponding to the first protocol stack and address information corresponding to the second protocol stack.

Regarding address information in the route corresponding to the first protocol stack, the address information in the route corresponding to the first protocol stack is obtained from the route advertisement message. That is, the address information corresponding to the first protocol stack in the route is address information issued by the second network device to the first network device. For example, the route includes a destination prefix, where the destination prefix in the route is a prefix corresponding to the first protocol stack. As another example, the route includes a destination address, where the destination address in the route is an address corresponding to the first protocol stack.

Regarding address information in the route corresponding to the second protocol stack, the address information in the route corresponding to the second protocol stack is obtained based on the network topology. For example, the route includes a next hop, where the next hop in the route is an IP address corresponding to the second protocol stack. The address information in the route corresponding to the second protocol stack is, for example, address information of an endpoint network device of the first link in the network topology.

In some embodiments, the route includes a next hop and an egress interface. For example, a first link is established between a first outgoing interface of a first network device and a second outgoing interface of a second network device. The first network device generates a route. The next hop in the route is the opposite interface address, i.e. the IP address corresponding to the second protocol stack, configured on the second outgoing interface. The route outgoing interface is a first outgoing interface. Alternatively, the next hop is included in the route without the outbound interface.

For example, referring to fig. 1, after receiving an IPv4 address 10.1.1.2 issued by a network device E (a second network device), a network device D (a first network device) generates a route based on the IPv4 address and an opposite interface address (i.e., IPv6 address 10:: 10) of a link DE in a network topology, where a destination address is the IPv4 address 10.1.1.2, and a next hop is an opposite interface address (i.e., IPv6 address 10:: 10) of the link DE, and an outgoing interface is a local interface (i.e., interface 3) of the link DE.

Optionally, the first network device generates the route based on an SPF algorithm. For example, the first network device obtains an identification of the second network device from the route advertisement message. The first network device locates the location of the second network device in the network topology based on the identification of the second network device. The first network device determines a shortest path from the first network device to the second network device from the network topology. The first network device takes the next network device of the first network device on the shortest path as the next hop, and takes the prefix in the route notification message as the destination prefix, thereby generating a route.

The route generation flow of the control plane is described in S201 to S204 above, and based on the route generation flow, the method shown in fig. 2 may further include a packet forwarding flow of the data plane, see S205 to S206 below.

S205, the first network equipment receives the data message.

The data message includes address information corresponding to the first protocol stack. For example, the destination address field of the data packet includes an IP address corresponding to the first protocol stack.

S206, the first network device forwards the data message to the address information corresponding to the second protocol stack based on the address information corresponding to the first protocol stack and the route.

For example, the first network device searches the routing table with the address information corresponding to the first protocol stack as an index, and obtains the address information corresponding to the second protocol stack. The first network device uses the address information corresponding to the second protocol stack as the next hop, and forwards the data message to the address information corresponding to the second protocol stack.

The method provided in this embodiment, the object of the routing computation is address information corresponding to the first protocol stack, and the result of the routing computation includes address information corresponding to the second protocol stack, that is, the object of the routing computation is allowed to have a different address family type from the result of the routing computation. In this way, a method of supporting dual stack hybrid route computation is achieved. Compared with the single-stack route calculation mode in the prior art, the embodiment configures one of the IPv4 address and the IPv6 address on the interface corresponding to the link, thereby being capable of supporting the requirement of dual-stack service without configuring the addresses of two protocol stacks, and saving IP address resources.

The process of obtaining the network topology by the first network device in the method shown in fig. 2 is illustrated below.

In some embodiments, the first network device obtains the network topology based on information of the at least one link. The information of one link includes, for example, a pair of IP addresses including address information of two end point network devices of the link. The information of how the first network device obtains the link includes a number of ways. For example, the first network device obtains information of each link to which the device is directly connected. Alternatively, the information of the link is advertised to the first network device by a neighbor network device of the first network device. Alternatively, the information of the link is configured on the first network device by means of a static configuration.

Taking the example that the second network device announces the information of the first link to the first network device, for example, the second network device generates a link announcement message, and the second network device sends the link announcement message to the first network device. The first network device receives a link notification message, and the first network device obtains the network topology according to address information of endpoint network devices of the first link.

The link notification message is used for publishing address information of the endpoint network equipment of the first link; in some embodiments, the link advertisement message includes address information of two endpoint network devices of the first link. From the perspective of protocol type, optionally, the link advertisement message is a BGP SPF message. Alternatively, the link advertisement message is an IGP message. For example, the link advertisement message IS an OSPF message or an IS-IS message.

The format and content of the link advertisement message are illustrated below by taking the link advertisement message as a BGP SPF message as an example.

Optionally, the link advertisement message includes BGP SPF link NLRI. For example, referring to fig. 5, the second network device sends the BGP SPF link NLRI shown in fig. 5 to the first network device, where the local node descriptor field includes an identification of the second network device and the link descriptor field includes an IP address of an interface on the second network device corresponding to the first link.

Optionally, the first network device further obtains a network topology based on the identification of the at least one network device. For example, the second network device generates a node advertisement message, and the second network device sends the node advertisement message to the first network device. The first network device receives the node advertisement message. The node advertisement message includes an identification of the second network device. The first network device obtains the identification of the second network device from the node notification message, and obtains the network topology according to the identification of the second network device. Optionally, the node advertisement message includes BGP SPF node NLRI shown in fig. 6.

Optionally, the node information, the link information and the prefix information are advertised by three different messages. In other words, the node advertisement message, the link advertisement message, and the route advertisement message are three different messages. Alternatively, the node information, the link information, and the prefix information are advertised through the same message. For example, the node information, the link information, and the prefix information are advertised by three different types of length values (type length value, TLVs) in the same message.

Some alternative embodiments of the present application relate to the application of BGP SPF protocol, which is briefly described below to aid understanding.

(1) BGP SPF protocol

BGP SPF protocol is a new type of routing protocol. The BGP SPF protocol computes paths based on a shortest path first (shortest path first, SPF) algorithm in an interior gateway protocol (interior gateway protocol, IGP) protocol, and uses a BGP link-state (BGP-LS) protocol-defined NLRI and TLV.

(2) Relationship between BGP SPF protocol and border gateway protocol (border gateway protocol, BGP) protocol

The BGP SPF protocol is an extension of the BGP protocol. The BGP SPF protocol corresponds to a new family of addresses in the BGP protocol.

Regarding the commonality of these two routing protocols, BGP SPF protocols use many mechanisms in BGP protocols, including but not limited to finite state machines in BGP protocols, encoding formats of BGP messages, processing of BGP messages, BGP attributes, BGP NLRI, and error handling mechanisms, among others. These mechanisms in the BGP protocol may be referred to in the introduction of RFC4271 and RFC 7606.

Regarding the distinction between these two routing protocols, BGP protocol is mainly used to support the transfer of routes between autonomous systems (autonomous system, AS). BGP protocols are not generally responsible for computing routes, and make decisions on paths based on policies and various attributes using routes provided by other routing protocols. BGP protocol is an overlay (overlay) protocol, and the underlay protocol of BGP protocol is typically an interior gateway protocol (interior gateway protocol, IGP) protocol. The BGP SPF protocol supports calculating the paths, and replaces the path decision process in the BGP protocol with calculating the paths based on the SPF algorithm. The BGP SPF protocol may be used as an underlay protocol. BGP SPF protocol may replace IGP protocol to some extent.

(3) Advantages of BGP SPF protocol over IGP protocol

The technical effects achieved by route calculation based on BGP SPF protocol include, but are not limited to, the following four aspects as compared to route calculation based on IGP.

A. Without requiring domain division

In large networks, it is often necessary to divide an autonomous system into different areas when IGP protocols are applied. The area is logically divided into different groups, each identified by an area number (area ID). The boundary of the area is a router, not a link. For example, the OSPF protocol may divide an autonomous system into different types of areas, such as a normal area, a tip (stub) area, a tip node area (NSSA), etc., and the IS-IS protocol may divide a routing domain into a backbone network and a non-backbone network. Whereas BGP SPF protocols generally do not have the concept of domain splitting, no domain splitting is required.

B. Aperiodic link state update

IGP protocols typically update link states throughout an area periodically. Flooding means that one router announces its own link state to adjacent routers, and the adjacent routers send the link state to other adjacent routers until all routers in the whole area have the same link state. The overhead of the device is large because the device needs to update the link state periodically. Whereas in BGP SPF protocols, the updating of link state is typically aperiodic, reducing the overhead of the device.

C. Incremental route advertisement

BGP SPF protocols typically advertise routes in an incremental manner, i.e., if the route is unchanged, no messages need to be sent to advertise the route. If the route is added, the route added to the neighbor is advertised, and if the route is deleted, the route deleted to the neighbor is advertised. By advertising routes incrementally, the number of route entries delivered by a full-volume advertising route can be avoided from being huge, affecting efficiency.

D. Flow control based on transmission control protocol (transmission control protocol, TCP)

IGP usually transmits routing protocol messages based on non-connection oriented protocols, so some additional mechanisms are required to ensure the transmission reliability of the routing protocol messages, for example, a master-slave negotiation mechanism is designed in the OSPF protocol to ensure the transmission reliability, and a periodic retransmission mode is designed in the routing information protocol (routing information protocol, RIP) to ensure the transmission reliability. The BGP SPF protocol is usually based on the TCP protocol to transmit routing protocol packets, so that the transmission reliability is high, and no additional design mechanism is usually required to ensure the transmission reliability.

(4)BGP SPF NLRI

BGP SPF NLRI is a type of Network Layer Reachability Information (NLRI) in BGP LS protocol for performing route computation. BGP SPF NLRI has an encapsulated format defined by RFC 7752. BGP SPF NLRI is further divided into three types, BGP SPF prefix NLRI, BGP SPF link NLRI, and BGP SPF node NLRI, respectively.

(5) BGP SPF prefix NLRI (BGP SPF prefix-NLRI)

BGP SPF prefix NLRI is used to publish prefix information. Fig. 3 is a schematic diagram of a format of a BGP SPF prefix NLRI provided in this embodiment, and as shown in fig. 3, the BGP SPF prefix NLRI includes a protocol ID (protocol-ID) field, an identifier (identifier) field, a local node descriptor (local node descriptors) field, and a prefix descriptor (prefix descriptors) field.

The local node descriptor field is used to carry the identity of the network device that issued the prefix (or source device of the prefix). For example, the local node descriptor field carries the AS number (autonomous system number) of the network device and the router-ID (router-ID).

Since the BGP SPF prefix NLRI carries the local node descriptor field and the prefix descriptor field, so as to indicate a binding relationship between the prefix and the network device that issues the prefix, a receiving end of the BGP SPF prefix NLRI can not only obtain the prefix, but also obtain which network device the prefix comes from, thereby triggering the receiving end to perform route calculation with the network device as a destination end.

The prefix descriptor field is used to carry an IP address prefix, for example, an IPv4 prefix or an IPv6 prefix. Optionally, the prefix descriptor field has an encoded structure of TLV. For example, the prefix descriptor field includes IP reachability information TLV (IP reachability information TLV) described in RFC 7752.

Fig. 4 is a schematic diagram of a prefix descriptor field according to the present embodiment. The prefix descriptor field shown in fig. 4 is, for example, the prefix descriptor field in the BGP SPF prefix NLRI shown in fig. 3. As shown in fig. 4, the prefix descriptor field specifically includes a type (type) field, a length (length) field, a prefix length (prefix length) field, and an IP prefix (IP prefix) field. Optionally, the value of the type (type) field in the prefix descriptor field, i.e., TLV type, is 265. Optionally, the IP prefix field carries a specific IPv4 prefix, and the prefix length field carries the length of the IPv4 prefix. Optionally, the IP prefix field carries a specific IPv6 prefix, and the prefix length field carries the length of the IPv6 prefix.

(6) BGP SPF link NLRI

BGP SPF links NLRI are used to publish link information. Fig. 5 is a schematic diagram of a format of a BGP SPF link NLRI provided in this embodiment, and as shown in fig. 5, the BGP SPF link NLRI includes a protocol ID (protocol-ID) field, an identifier (identifier) field, a local node descriptor (local node descriptors) field, a remote node descriptor (remote node descriptors), and a link descriptor (link descriptor) field.

The local node descriptor field in the BGP SPF link NLRI is used to carry the identity of the local end of the link (local end) network device. The remote node descriptor field is used to carry the identity of the remote end point (remote end) network device of the link.

For example, the local node descriptor field is used to carry the AS number of the local endpoint network device of the link and the router-ID of the local endpoint network device, while the remote node descriptor field carries the AS number of the remote endpoint network device of the link and the router-ID of the remote endpoint network device. Optionally, the link descriptor field includes a pair of IP addresses, i.e., an interface address of a local endpoint network device of the link and an interface address of a remote endpoint network device of the link.

For example, network device a transmits BGP SPF link NLRI to publish link AB between network device a and network device B. Link AB is the link between interface a of network device a and interface B of network device B. In BGP SPF link NLRI, the local node descriptor field includes an identification of network device a, the remote node descriptor field includes an identification of network device B, and the link descriptor field includes an IP address of interface a and an IP address of interface B.

(7) BGP SPF node NLRI

BGP SPF node NLRI is used to publish node information. Fig. 6 is a schematic diagram of a format of a BGP SPF node NLRI provided in this embodiment, and as shown in fig. 6, the BGP SPF node NLRI includes a protocol ID (protocol-ID) field, an identifier (identifier) field, and a local node descriptor (local node descriptors) field.

The method shown in fig. 2 is illustrated below in conjunction with a specific scenario, which illustrates a scenario in which BGP SPF routing domains are spliced and deployed with IGP routing domains.

Fig. 7 is a schematic view of a scenario in which BGP SPF routing domains and IGP routing domains are spliced and deployed according to the present embodiment. In the scenario shown in fig. 7, each link between network devices in the IGP routing domain is an IPv4 link, and each link between network devices in the BGP SPF routing domain is an IPv6 link. The CE1 is accessed with an IPv4 user and an IPv6 user, and the CE2 is also accessed with the IPv4 user and the IPv6 user.

For inter-domain splice nodes of the BGP SPF routing domain and the IGP routing domain, such as network equipment C and network equipment D, the inter-domain splice nodes introduce routing prefixes such as IGP routing prefixes 10.1.1.1, 10.1.1.2, 20.1.1.1, 20.1.1.2 and access user address prefixes 200.1.1.2, 200:2 on network equipment A and network equipment B into the BGP SPF routing domain; after the prefixes are introduced by the network device C and the network device D, the prefixes are issued to other network devices in the BGP SPF routing domain through a BGP SPF protocol. After other network devices receive the prefixes, the network devices which issue the prefixes search corresponding nodes in the IPv6 topology which is matched with the BGP SPF routing domain, and an IPv4 prefix destination route or an IPv6 prefix destination route which takes the IPv6 address as the next hop is generated.

Fig. 8 is a schematic view of a scenario in which another BGP SPF routing domain provided in the present embodiment is spliced and deployed with an IGP routing domain. In the scenario shown in fig. 8, the IGP routing domain includes IPv4 links and IPv6 links, which corresponds to the IGP routing domain deployed based on a hybrid protocol stack. The BGP SPF routing domain also includes an IPv4 link and an IPv6 link, which is equivalent to BGP SPF routing domain deployment based on a hybrid protocol stack. The CE1 is accessed with an IPv4 user and an IPv6 user, and the CE2 is also accessed with the IPv4 user and the IPv6 user. For inter-domain splice nodes of the BGP SPF routing domain and the IGP routing domain, such as network equipment C and network equipment D, introducing routing prefixes of 10.1.1.1, 10.1.1.2, 30:10, 30:20, access user address prefixes 200.1.1.2 on network equipment A and network equipment B, 200:2 and the like into the BGP SPF routing domain; after the prefixes are introduced into the network equipment C and the network equipment D, the prefixes are issued to other nodes in the BGP SPF routing domain through the BGP SPF protocol, and after the other nodes receive the prefixes, the corresponding nodes in the mixed topology containing the IPv6 link and the IPv4 link of the BGP SPF routing domain are searched according to the nodes for issuing the prefixes, and an IPv4 prefix destination route or an IPv6 prefix destination route taking the IPv6 address as a next hop or an IPv6 prefix destination route taking the IPv6 address as the next hop or an IPv4 prefix destination route taking the IPv4 address as the next hop is generated.

The method illustrated in fig. 2 above is illustrated below in connection with four examples. In the following examples, network device E is an illustration of a second network device in the method of fig. 2, and network device D, network device F, or network device C is an illustration of a first network device in the method of fig. 2. BGP SPF prefix-NLRI is an illustration of the route advertisement message in the method shown in fig. 2.

Example one: BGP SPF routing domain is pure IPv6 base network deployment

Example one includes the following steps one to four.

Step one, introducing an IPv4 prefix 100.1.1.2 from an IPv6 edge network device E of the BGP SPF routing domain. Network device E encapsulates this IPv4 prefix 100.1.1.2 into BGP SPF prefix-NLRI. Network device E publishes (including network device D, network device F, and network device C) BGP SPF prefix-NLRI to network devices other than network device E in the BGP SPF routing domain. After each network device in the BGP SPF routing domain (including network device D, network device F, and network device C) receives the BGP SPF prefix-NLRI, the routing computation to the destination address 100.1.1.2 is performed.

The BGP SPF prefix-NLRI is encapsulated according to RFC7752, in the format shown in fig. 3. The prefix descriptors TLV format in BGP SPF prefix-NLRI is shown in fig. 4.

And step two, each network device in the BGP SPF routing domain calculates an IPv4 routing with a destination address of 100.1.1.2. Each network device in the BGP SPF routing domain generates an IPv4 forwarding table based on the IPv4 route. The next hop in the IPv4 forwarding table entry is an IPv6 address, and the outgoing interface in the IPv4 forwarding table entry is an interface to the neighbor node. For example, network device C calculates a destination address 100.1.1.2 route with a next hop of 30:10 and an egress interface of interface 6.

And thirdly, receiving the traffic with the destination address of 100.1.1.2 by a network device in the BGP SPF routing domain, and inquiring an IPv4 forwarding table item by the network device according to the destination address of the traffic to obtain an IPv6 next hop and an outgoing interface. And the network equipment forwards the flow to the next network equipment after encapsulating the message according to the IPv6 next hop and the outgoing interface until the flow reaches the destination address.

Step four, for the scene of splicing the IPv6 type BGP SPF routing domain and the IPv4 type IGP routing domain shown in fig. 9, introducing the IPv4 address information of the IGP routing domain into the BGP SPF routing domain on the network device D or the network device C, and calculating the IPv4 routing of the IGP routing domain to which the destination address belongs on each network device, such as the network device E or the network device F, in the BGP SPF routing domain, where the calculation process is the same as that described in step one to step three.

By the method of the first example, a scene is deployed for the IPv 6-only basic network in the BGP SPF routing domain, so that the BGP SPF routing protocol supports single-stack topology to perform IPv4 and IPv6 dual-stack mixed routing calculation.

Example two: BGP SPF routing domain is pure IPv4 base network deployment

Example two includes the following steps one to four.

Step one, introducing an IPv6 prefix 100:2 from IPv4 edge network equipment F of the BGP SPF routing domain, and encapsulating the IPv6 prefix 100:2 into a BGP SPF prefix NLRI (BGP SPF prefix-NLRI) by the network equipment F. Network device F issues BGP SPF prefix-NLRI to other network devices (including network device D, network device E, and network device C) in the BGP SPF routing domain other than network device F. After each network device (including network device D, network device E and network device C) in the BGP SPF routing domain receives BGP SPF prefix-NLRI, the routing calculation to the destination address 100:2 is carried out respectively.

And step two, each network device in the BGP SPF routing domain calculates the IPv6 routing of the destination address 100:2. Each network device of the BGP SPF routing domain generates an IPv6 forwarding table based on the IPv6 route. The next hop in the IPv6 forwarding table entry is an IPv4 address, and the outgoing interface in the IPv6 forwarding table entry is an interface to the neighbor node. For example, network device D calculates the destination address 100:2 route, the next hop in the route is 50.1.1.1, and the egress interface is interface 3.

And thirdly, a network device in the BGP SPF routing domain receives the flow with the destination address of 100:2, queries an IPv6 forwarding table item according to the destination address of the flow to obtain an IPv4 next hop and an IPv outlet interface, and forwards the flow to the next network device until the flow reaches the destination address after the network device encapsulates the message according to the IPv4 next hop and the IPv outlet interface.

Step four, for the scene of splicing the IPv4 type BGP SPF routing domain and the IPv6 type IGP routing domain shown in fig. 10, introducing the IPv6 address information of the IGP routing domain into the BGP SPF routing domain on the network device D or the network device C, and calculating the IPv6 routing of the IGP routing domain to which the destination address belongs on each network device, such as the network device E or the network device F, in the BGP SPF routing domain, where the calculation process is the same as that described in step one to step three.

By the method provided by the second example, the BGP SPF routing domain is a pure IPv4 basic network deployment scene, and the BGP SPF routing protocol supports single stack topology to perform IPv4 and IPv6 dual stack mixed routing calculation.

Example three: BGP SPF routing domains are deployed for dual stack links, i.e., dual stack addresses are configured for a link interface between network devices.

As shown in fig. 11, the interface of the same link between the network device C and the network device F configures an IPv4 address and an IPv6 address, i.e., a dual stack address. BGP SPF routing domain collection forms a topology. Optionally, the network device generates an IPv4 topology and an IPv6 topology, respectively. Alternatively, the network device generates a topology that includes IPv4 links and IPv6 links, which may be referred to as a hybrid dual stack topology.

Illustratively, the IPv4 topology generated by the network device is shown in fig. 12, the IPv6 topology generated by the network device is shown in fig. 13, and the hybrid dual stack topology generated by the network device is shown in fig. 14.

When the network equipment calculates the IPv4 route or the IPv6 route, matching is carried out according to the topology result, and the IPv4 next hop or the IPv6 next hop is used. The route forwarding behavior is handled as in instance one and instance two.

By the method provided by the third example, the BGP SPF routing domain is a dual-stack link deployment scene, can simultaneously support IPv4 or IPv6 prefix route calculation, and the next hop of the route is matched according to a topology result to use the next hop of IPv4 or IPv 6.

Example four: BGP SPF routing domains are deployed for IPv4 links and IPv6 links, i.e., there are different link address family types between different network devices.

As shown in fig. 15, there are IPv4 links, IPv6 links, and dual stack links between different network devices in the BGP SPF routing domain; optionally, the network device calculates the topology independently based on the IPv4 link or the IPv6 link, respectively, or the network device calculates the topology based on a hybrid of the IPv4 link and the IPv6 link. When the network equipment calculates the IPv4 prefix route or the IPv6 prefix route, the network equipment performs matching according to the topology result, and uses the IPv4 next hop or the IPv6 next hop. The route forwarding behavior is handled as in instance one and instance two.

By the method provided by the fourth example, the IPv4 link and the IPv6 link are spliced and deployed in the BGP SPF routing domain, so that IPv4 or IPv6 prefix route calculation can be supported at the same time, and the next hop of the route is matched according to the topology result to use the next hop of IPv4 or IPv 6.

Summarizing, the method provided by the four examples saves IPv4/IPv6 address resources. In addition, the single-stack network supports the double-stack service requirement, simplifies the network operation and maintenance and reduces the network equipment overhead. In addition, a smooth evolution scheme is provided for upgrading and reforming the IPv6 network for the IPv4 base network of the existing network.

Fig. 16 is a schematic structural diagram of a route generating device 600 according to an embodiment of the present application. The route generating device 600 includes an obtaining unit 601, a receiving unit 602, and a generating unit 603. Optionally, the route generating device 600 further comprises a sending unit 604.

Optionally, in view of the application scenario shown in fig. 1, the route generating device 600 shown in fig. 16 is provided in the network device D in the method flow shown in fig. 1, the receiving unit 602 is configured to receive the route advertisement packet shown in fig. 1, the generating unit 603 is configured to generate a route in the routing table or forwarding table shown in fig. 1, and the obtaining unit 601 is configured to obtain the network topology shown in fig. 1.

Alternatively, as seen in connection with the method flow shown in fig. 2, the route generating device 600 shown in fig. 16 is provided in the first network device in the method flow shown in fig. 2, the obtaining unit 601 is configured to execute S201, the receiving unit 602 is configured to execute S203, and the generating unit 603 is configured to execute S204. Optionally, the receiving unit 602 is further configured to perform S205, and the transmitting unit 604 is further configured to perform S206.

The embodiment of the apparatus depicted in fig. 16 is merely illustrative, and for example, the division of the above units is merely a logical function division, and there may be other manners of division in actual implementation, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. The functional units in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The various elements in route generation device 600 may be implemented, in whole or in part, by software, hardware, firmware, or any combination thereof.

Some possible implementations using hardware or software to implement the various functional units in the route generation device 600 are described below in connection with the network device 800 described below.

In the case of a software implementation, for example, the above-described obtaining unit 601 and generating unit 603 are implemented by software functional units generated after the program codes stored in the memory 802 are read by at least one processor 801 in fig. 18.

In the case of a hardware implementation, for example, each of the units described above in fig. 16 is implemented by different hardware in a network device, respectively, for example, the obtaining unit 601 is implemented by a part of processing resources (for example, one core or two cores in a multi-core processor) in at least one processor 801 in fig. 18, and the generating unit 603 is implemented by the rest of processing resources (for example, other cores in the multi-core processor) in at least one processor 801 in fig. 18, or is implemented by a programmable device such as a field-programmable gate array (field-programmable gate array, FPGA) or a coprocessor. The receiving unit 602 is implemented by the network interface 803 in fig. 18.

Fig. 17 is a schematic structural diagram of a forwarding device 700 for data packets according to an embodiment of the present application. The forwarding device 700 of the data packet includes a receiving unit 701 and a transmitting unit 702.

Optionally, as seen in connection with the method flow shown in fig. 2, the forwarding apparatus 700 of the data packet shown in fig. 17 is provided in the first network device in the method flow shown in fig. 2, the receiving unit 701 is configured to execute S205, and the sending unit 702 is configured to execute S206.

The embodiment of the apparatus depicted in fig. 17 is merely illustrative, and for example, the division of the above units is merely a logical function division, and there may be other manners of division in actual implementation, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. The functional units in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The various elements in the forwarding device 700 of the data packet are implemented in whole or in part by software, hardware, firmware, or any combination thereof.

Some possible implementations of implementing the respective functional units in the forwarding device 700 of the data packet using hardware or software are described below in connection with the network device 800 described below.

In the case of a software implementation, for example, the receiving unit 701 and the transmitting unit 702 are implemented by software functional units generated after the program codes stored in the memory 802 are read by at least one processor 801 in fig. 18.

In the case of a hardware implementation, for example, each of the units described above in fig. 17 is implemented by different hardware in a network device, for example, the receiving unit 701 and the transmitting unit 702 are implemented by the network interface 803 in fig. 18, respectively.

The basic hardware structure of the network device is illustrated below.

Fig. 18 is a schematic structural diagram of a network device 800 according to an embodiment of the present application. The network device 800 includes at least one processor 801, memory 802, and at least one network interface 803.

Alternatively, the network device 800 shown in fig. 18 is the network device D in fig. 1, as seen in connection with the application scenario shown in fig. 1.

Alternatively, as seen in connection with fig. 2, the network device 800 shown in fig. 18 is the first network device in the flow of the method shown in fig. 2, the processor 801 is configured to execute S201 and S204, and the network interface 803 is configured to execute S203, S205, and S206.

The processor 801 is, for example, a general-purpose central processing unit (central processing unit, CPU), a network processor (network processer, NP), a graphics processor (graphics processing unit, GPU), a neural-network processor (neural-network processing units, NPU), a data processing unit (data processing unit, DPU), a microprocessor, or one or more integrated circuits for implementing aspects of the present application. For example, the processor 801 includes application-specific integrated circuits (application-specific integrated circuit, ASICs), programmable logic devices (programmable logic device, PLDs), or combinations thereof. PLDs are, for example, complex programmable logic devices (complex programmable logic device, CPLD), field-programmable gate arrays (field-programmable gate array, FPGA), general-purpose array logic (generic array logic, GAL), or any combination thereof.

The Memory 802 is, for example, but not limited to, a read-only Memory (ROM) or other type of static storage device that can store static information and instructions, as well as a random access Memory (random access Memory, RAM) or other type of dynamic storage device that can store information and instructions, as well as an electrically erasable programmable read-only Memory (electrically erasable programmable read-only Memory, EEPROM), compact disc read-only Memory (compact disc read-only Memory) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media, or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Optionally, the memory 802 is independent and is connected to the processor 801 by an internal connection 804. Alternatively, memory 802 and processor 801 are integrated together.

The network interface 803 uses any transceiver-like device for communicating with other devices or communication networks. The network interface 803 includes, for example, at least one of a wired network interface or a wireless network interface. The wired network interface is, for example, an ethernet interface. The ethernet interface is, for example, an optical interface, an electrical interface, or a combination thereof. The wireless network interface is, for example, a wireless local area network (wireless local area networks, WLAN) interface, a cellular network interface, a combination thereof, or the like.

In some embodiments, processor 801 includes one or more CPUs, such as CPU0 and CPU1 shown in fig. 18.

In some embodiments, network device 800 optionally includes multiple processors, such as processor 801 and processor 805 shown in fig. 18. Each of these processors is, for example, a single-core processor (single-CPU), and is, for example, a multi-core processor (multi-CPU). A processor herein may optionally refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

In some embodiments, network device 800 also includes internal connection 804. The processor 801, the memory 802 and the at least one network interface 803 are connected by an internal connection 804. The internal connections 804 include vias that communicate information between the components described above. Optionally, the internal connection 804 is a board or bus. Optionally, the internal connections 804 are divided into address buses, data buses, control buses, and the like.

In some embodiments, network device 800 also includes an input-output interface 806. An input-output interface 806 is connected to the internal connection 804.

Alternatively, the processor 801 implements the method in the above embodiment by reading the program code 810 stored in the memory 802, or the processor 801 implements the method in the above embodiment by internally storing the program code. In the case where the processor 801 implements the method in the above embodiment by reading the program code 810 stored in the memory 802, the program code implementing the method provided by the embodiment of the present application is stored in the memory 802.

For more details on the implementation of the above-described functions by the processor 801, reference is made to the description of the previous method embodiments, which is not repeated here.

Referring to fig. 19, fig. 19 is a schematic structural diagram of a network device according to an embodiment of the present application. The network device 900 includes: a main control board 910 and an interface board 930.

Alternatively, the network device 900 shown in fig. 19 is the network device D in fig. 1, as viewed in connection with the application scenario shown in fig. 1.

Optionally, as seen in connection with fig. 2, the network device 900 shown in fig. 19 is a first network device in the method flow shown in fig. 2, the main control board 910 is used to execute S201, S203, and S204, and the interface board 930 is used to execute S205 and S206.

The main control board is also called a main processing unit (main processing unit, MPU) or a routing processing card (route processor card), and the main control board 910 is used for controlling and managing various components in the network device 900, including routing computation, device management, device maintenance, and protocol processing functions. The main control board 910 includes: a central processing unit 911 and a memory 912.

The interface board 930 is also referred to as a line interface unit card (line processing unit, LPU), line card, or service board. The interface board 930 is used to provide various service interfaces and to implement forwarding of data packets. The service interfaces include, but are not limited to, ethernet interfaces, such as flexible ethernet service interfaces (flexible ethernet clients, flexE clients), POS (packet over sONET/SDH) interfaces, etc. The interface board 930 includes: central processor 931, network processor 932, forwarding table entry memory 934, and physical interface cards (physical interface card, PIC) 933.

The central processor 931 on the interface board 930 is used to control and manage the interface board 930 and communicate with the central processor 911 on the main control board 910.

The network processor 932 is configured to implement forwarding processing of the packet. The network processor 932 is in the form of, for example, a forwarding chip. Specifically, the network processor 932 is configured to forward the received packet based on the forwarding table stored in the forwarding table entry memory 934, and if the destination address of the packet is the address of the network device 900, upload the packet to the CPU (e.g. the central processing unit 911) for processing; if the destination address of the message is not the address of the network device 900, the next hop and the outbound interface corresponding to the destination address are found from the forwarding table according to the destination address, and the message is forwarded to the outbound interface corresponding to the destination address. The processing of the uplink message comprises the following steps: processing a message input interface and searching a forwarding table; and (3) processing a downlink message: forwarding table lookup, etc.

The physical interface card 933 is used to implement the docking function of the physical layer, from which the original traffic enters the interface board 930, and from which the processed messages are sent out from the physical interface card 933. A physical interface card 933, also referred to as a daughter card, may be mounted on the interface board 930 and is responsible for converting the optical signals into messages and forwarding the messages to the network processor 932 for processing after a validity check. In some embodiments, the central processor may also perform the functions of the network processor 932, such as implementing software forwarding based on a general purpose CPU, so that the network processor 932 is not needed in the physical interface card 933.

Optionally, the network device 900 includes a plurality of interface boards, for example, the network device 900 further includes an interface board 940, the interface board 940 includes: a central processor 941, a network processor 942, a forwarding table entry memory 944, and a physical interface card 943.

Optionally, the network device 900 further comprises a switch fabric 920. The switching fabric 920 is also referred to as, for example, a switching fabric unit (switch fabric unit, SFU). In the case of a network device having a plurality of interface boards 930, the switch fabric 920 is used to complete data exchange between the interface boards. For example, communication between interface board 930 and interface board 940 is via, for example, switch fabric 920.

The main control board 910 is coupled to the interface board 930. For example. The main control board 910, the interface board 930 and the interface board 940 are connected with the system backboard through a system bus to realize intercommunication among the switching network boards 920. In one possible implementation, an inter-process communication protocol (inter-process communication, IPC) channel is established between the main control board 910 and the interface board 930, and communication is performed between the main control board 910 and the interface board 930 through the IPC channel.

Logically, network device 900 includes a control plane that includes a main control board 910 and a central processor 931, and a forwarding plane that includes various components that perform forwarding, such as a forwarding table entry memory 934, a physical interface card 933, and a network processor 932. The control plane performs the functions of router, generating forwarding table, processing signaling and protocol messages, configuring and maintaining the status of the device, etc., and the control plane issues the generated forwarding table to the forwarding plane, where the network processor 932 forwards the message received by the physical interface card 933 based on the forwarding table issued by the control plane. The forwarding table issued by the control plane is stored, for example, in forwarding table entry memory 934. In some embodiments, the control plane and forwarding plane are, for example, completely separate and not on the same device.

Operations on interface board 940 are consistent with those of interface board 930 and will not be described again for brevity. It should be understood that the network device 900 of the present embodiment may correspond to the first network device in the foregoing method embodiments, and the main control board 910, the interface boards 930 and/or 940 in the network device 900 implement, for example, functions and/or various steps implemented by the first network device in the foregoing method embodiments, which are not described herein for brevity.

The master control board may have one or more pieces, and the plurality of pieces include, for example, a main master control board and a standby master control board. The interface boards may have one or more, the more data processing capabilities the network device is, the more interface boards are provided. The physical interface card on the interface board may also have one or more pieces. The switching network board may not be provided, or may be provided with one or more blocks, and load sharing redundancy backup can be jointly realized when the switching network board is provided with the plurality of blocks. Under the centralized forwarding architecture, the network device may not need to exchange network boards, and the interface board bears the processing function of the service data of the whole system. Under the distributed forwarding architecture, the network device may have at least one switching fabric, through which data exchange between multiple interface boards is implemented, providing high-capacity data exchange and processing capabilities. Therefore, the data access and processing power of the network devices of the distributed architecture is greater than that of the devices of the centralized architecture. Alternatively, the network device may be in the form of only one board card, i.e. there is no switching network board, the functions of the interface board and the main control board are integrated on the one board card, and the central processor on the interface board and the central processor on the main control board may be combined into one central processor on the one board card, so as to execute the functions after stacking the two, where the data exchange and processing capability of the device in this form are low (for example, network devices such as a low-end switch or a router). The specific architecture employed is not limited in any way herein, depending on the specific networking deployment scenario.

In this specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are referred to each other, and each embodiment is mainly described as a difference from other embodiments.

A refers to B, referring to a simple variation where A is the same as B or A is B.

The terms first and second and the like in the description and in the claims of embodiments of the application, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order of the objects, and should not be interpreted to indicate or imply relative importance. For example, a first network device and a second network device are used to distinguish between different network devices, rather than to describe a particular order of network devices, nor should the first network device be understood to be more important than the second network device.

Information (including but not limited to user equipment information, user personal information, etc.), data (including but not limited to data for analysis, stored data, presented data, etc.), and signals, which are all authorized by the user or sufficiently authorized by the parties, and the collection, use, and processing of the relevant data require compliance with relevant laws and regulations and standards of the relevant country and region. For example, address information referred to in the present application is obtained under a sufficient authorization.

The above-described embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, optical fiber, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid State Disk (SSD)), etc.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.

Claims

1. A method of route generation, comprising:

the first network device obtains a network topology;

2. The method of claim 1, wherein the address information of the endpoint network devices of all links in the network topology other than the first link is address information corresponding to a second protocol stack.

3. The method of claim 1, wherein the network topology further comprises a second link, and wherein an endpoint network device of the second link comprises address information corresponding to the first protocol stack.

4. The method of claim 1, wherein the network topology comprises a dual stack link, and wherein an endpoint network device of the dual stack link comprises address information corresponding to a first protocol stack and address information corresponding to a second protocol stack.

5. The method of claim 1, wherein the second network device belongs to a BGPSPF routing domain and to an interior gateway protocol, IGP, routing domain, and wherein the address information corresponding to the first protocol stack is address information of a third network device in the IGP routing domain; or alternatively, the process may be performed,

the address information corresponding to the first protocol stack is address information of a user equipment to which the second network equipment is connected.

6. The method according to any one of claims 1 to 5, wherein the first network device obtains a network topology, comprising:

7. The method according to any one of claims 1 to 6, wherein the route advertisement message is a border gateway protocol shortest path first calculation BGPSPF message.

8. The method according to any of claims 1 to 7, wherein the first protocol stack is an internet protocol version 4 IPv4 protocol stack and the second protocol stack is an internet protocol version 6 IPv6 protocol stack; or alternatively, the process may be performed,

9. The data message forwarding method is characterized by comprising the following steps:

10. The method of claim 9, wherein the first protocol stack is an internet protocol version 4 IPv4 protocol stack and the second protocol stack is an internet protocol version 6 IPv6 protocol stack; or alternatively, the process may be performed,

11. A route generation device, comprising:

an obtaining unit configured to obtain a network topology;

a receiving unit, configured to receive a route advertisement packet from a second network device, where the route advertisement packet is used to issue address information corresponding to a first protocol stack;

and the generating unit is used for generating a route, wherein the route comprises address information corresponding to the first protocol stack and address information corresponding to a second protocol stack, and the address information corresponding to the second protocol stack is the address information of the endpoint network equipment of the first link in the network topology.

12. The apparatus of claim 11, wherein address information of endpoint network devices of all links other than the first link in the network topology is address information corresponding to a second protocol stack.

13. The apparatus of claim 11, wherein the network topology further comprises a second link, an endpoint network device of the second link comprising address information corresponding to the first protocol stack.

14. The apparatus of claim 11, wherein the network topology comprises a dual stack link, and wherein an endpoint network device of the dual stack link comprises address information corresponding to a first protocol stack and address information corresponding to a second protocol stack.

15. The apparatus of claim 11, wherein the second network device belongs to a BGPSPF routing domain and to an interior gateway protocol, IGP, routing domain, and wherein the address information corresponding to the first protocol stack is address information of a third network device in the IGP routing domain; or alternatively, the process may be performed,

16. The apparatus according to any one of claims 11 to 15, wherein the obtaining unit is configured to receive a link advertisement message, where the link advertisement message is configured to issue address information of an endpoint network device of the first link; and obtaining the network topology according to the address information of the endpoint network equipment of the first link.

17. The apparatus according to any one of claims 11 to 16, wherein the route advertisement message is a border gateway protocol shortest path first calculation BGPSPF message.

18. The apparatus according to any one of claims 11 to 17, wherein the first protocol stack is an internet protocol version 4 IPv4 protocol stack and the second protocol stack is an internet protocol version 6 IPv6 protocol stack; or alternatively, the process may be performed,

19. A data message forwarding device, comprising:

a receiving unit, configured to receive a data packet, where the data packet includes address information corresponding to a first protocol stack;

and the sending unit is used for forwarding the data message to the address information corresponding to the second protocol stack based on the address information corresponding to the first protocol stack and the route, wherein the route comprises the address information corresponding to the first protocol stack and the address information corresponding to the second protocol stack.

20. The apparatus of claim 19, wherein the first protocol stack is an internet protocol version 4 IPv4 protocol stack and the second protocol stack is an internet protocol version 6 IPv6 protocol stack; or alternatively, the process may be performed,

21. A network device comprising a processor for executing instructions to cause the network device to perform the method of any one of claims 1 to 10, and a network interface for receiving or transmitting messages.

22. A computer readable storage medium, characterized in that at least one instruction is stored in the storage medium, which instructions, when run on a processor, cause the processor to perform the method according to any of claims 1-10.

23. A computer program product comprising one or more computer program instructions which, when loaded and run by a computer, cause the computer to perform the method of any of claims 1-10.