WO2024061184A1

WO2024061184A1 - Correspondence acquisition method, parameter notification method, and apparatus, device and medium

Info

Publication number: WO2024061184A1
Application number: PCT/CN2023/119562
Authority: WO
Inventors: 陈思雨; 段方红; 谢经荣; 谷丁云
Original assignee: 华为技术有限公司
Priority date: 2022-09-22
Filing date: 2023-09-19
Publication date: 2024-03-28
Also published as: CN117749700A

Abstract

The present application belongs to the technical field of communications. Provided are a correspondence acquisition method, a parameter notification method, and an apparatus, a device and a medium. In the present application, a second forwarding device receives two parameter sets from a first forwarding device and a third forwarding device in a first station; according to the fact that anycast labels included in the two parameter sets each identify the first station, a BFR-ID of the first forwarding device and a BFR-ID of the third forwarding device are embodied in the same correspondence, that is, a plurality of devices in the same station are bound together by means of anycast labels, such that when a data message is received, if a link which reaches one device in the first station fails, an F-BM in a correspondence can be matched according to a bit string in the data message, and the data message is directly forwarded to the next hop in the correspondence, without the need for recalculating the next hop by means of routing convergence, thereby increasing the speed of convergence switching, and thus realizing flow protection.

Description

Correspondence acquisition methods, parameter notification methods, devices, equipment and media

This application claims the priority of the Chinese patent application with application number 202211550567.7 and the invention title "Correspondence Obtaining Method, Parameter Notification Method, Device, Equipment and Medium" submitted on December 05, 2022, and claims in 2022 The application number 202211160684.2 submitted on September 22 and the invention title is "a BIER Anycast traffic protection method and device" have priority. The entire contents of the above-mentioned patent applications are incorporated by reference into this application.

Technical field

The present application relates to the field of communication technology, and in particular to a method for obtaining a correspondence relationship, a parameter notification method, a device, equipment and a medium.

Background technique

In the scenario of bit indexed explicit replication (BIER), when a BFR that the BIER forwarding path passes through fails or the link where the BFR is located fails, other BFRs need to unicast the route to the BFER one by one. Hop convergence requires packets to be forwarded through the converged route, resulting in slower convergence switching.

Contents of the invention

This application provides a corresponding relationship acquisition method, parameter notification method, device, equipment and medium, which can improve the speed of convergence switching and achieve traffic protection. The technical solution is as follows.

In a first aspect, a method for obtaining a corresponding relationship is provided, including: a second forwarding device in a second site receives a first parameter set from a first forwarding device in a first site, the first parameter set including a first anycast label, a BFR-ID of the first forwarding device, and a BFR prefix of the first forwarding device, and the first anycast label is used to identify the first site; the second forwarding device receives a second parameter set from a third forwarding device in the first site, the second parameter set including a second anycast label, the BFR-ID of the third forwarding device, and the BFR prefix of the third forwarding device, and the second anycast label is used to identify the first site; the second forwarding device receives a second parameter set from a third forwarding device in the first site, the second parameter set including a second anycast label, the BFR-ID of the third forwarding device, and the BFR prefix of the third forwarding device, and the second anycast label is used to identify the first site; the second forwarding device and the BFR-ID of the third forwarding device, wherein the first correspondence includes a forwarding bit mask F-BM matching the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, the first anycast label, and a next hop matching the BFR prefix of the first forwarding device; the second forwarding device obtains a second correspondence based on the second parameter set and the BFR-ID of the first forwarding device, wherein the second correspondence includes an F-BM matching the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, the second anycast label, and a next hop matching the BFR prefix of the third forwarding device.

In the above method, the second forwarding device receives two parameter sets from the first forwarding device and the third forwarding device in the first site. According to the anycast tags contained in the two parameter sets both identify the first site, the first forwarding device The BFR-ID of the device and the third forwarding device are reflected in the same corresponding relationship, which is equivalent to binding multiple devices in the same site together through anycast labels. Then when a data packet is received, if it arrives If one of the devices in the first site has a link failure, it can match the F-BM in the corresponding relationship based on the bit string in the data message, and forward the data message directly to the next hop in the corresponding relationship without going through routing. Convergence recalculates the next hop, thus increasing the speed of convergence switching and achieving traffic protection.

In some implementations, the second forwarding device obtains the first corresponding relationship based on the first parameter set and the BFR-ID of the third forwarding device, including: the second forwarding device based on the first any broadcast tag and the second anycast tag, and determine that the first forwarding device and the third forwarding device belong to the first site; the second forwarding device is based on the BFR-ID of the first forwarding device and The BFR-ID of the third forwarding device obtains the F-BM; the second forwarding device obtains the BFR prefix based on the F-BM, the first anycast tag and the first forwarding device. The first correspondence relationship includes the F-BM, the first anycast label, and the BFR prefix of the first forwarding device.

In some implementations, the second forwarding device obtains the BFR-ID based on the first parameter set and the third forwarding device. The first correspondence relationship includes: the second forwarding device determines that the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag. ; The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device; the second forwarding device obtains the F-BM based on the first forwarding device The BFR prefix determines the first outbound interface on the second forwarding device that reaches the first forwarding device; the second forwarding device is based on the F-BM, the first anycast label, the first The BFR prefix of the forwarding device and the first outbound interface are used to obtain the first corresponding relationship. The first corresponding relationship includes the F-BM, the first anycast label, and the BFR of the first forwarding device. prefix and the first outbound interface.

In some implementations, the second forwarding device obtains the second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device, including: the second forwarding device based on the first any The broadcast tag and the second anycast tag determine that the first forwarding device and the third forwarding device both belong to the first site; the second forwarding device is based on the BFR-ID of the first forwarding device and The BFR-ID of the third forwarding device obtains the F-BM; the second forwarding device obtains the BFR prefix based on the F-BM, the second anycast tag and the third forwarding device. The second correspondence relationship includes the F-BM, the second anycast label, and the BFR prefix of the third forwarding device.

In some implementations, the second forwarding device obtains the second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device, including: the second forwarding device based on the first any The broadcast tag and the second anycast tag determine that the first forwarding device and the third forwarding device both belong to the first site; the second forwarding device is based on the BFR-ID of the first forwarding device and The BFR-ID of the third forwarding device is used to obtain the F-BM; the second forwarding device determines that the third forwarding device is reached on the second forwarding device based on the BFR prefix of the third forwarding device. The second outbound interface; the second forwarding device obtains the second corresponding response based on the F-BM, the second anycast label, the BFR prefix of the third forwarding device and the second outbound interface The second corresponding relationship includes the F-BM, the second anycast label, the BFR prefix of the third forwarding device, and the second outbound interface.

In some embodiments, both the first anycast label and the second anycast label are labels; or, the first anycast label and the second anycast label are both IPv6 destination addresses.

In some implementations, the first parameter set further includes the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the BIER subdomain in which the first forwarding device is located. One or more of the identifiers; the second parameter set also includes the bit string length BSL of the third forwarding device, the set identifier SI to which the third forwarding device belongs and the location where the third forwarding device is located. Identifier of one or more of the BIER subdomains.

In some embodiments, the second forwarding device in the second site receiving the first parameter set from the first forwarding device in the first site includes: the second forwarding device receiving the first parameter set from the first forwarding device. A notification message, the first notification message includes a BIER information sub-TLV, the BIER information sub-TLV includes the first anycast label; the second forwarding device receives a third forwarding message from the first site The second parameter set of the device includes: the second forwarding device receives a second notification message from the first forwarding device in the first site, the second notification message includes a BIER information sub-TLV, and the BIER The information sub-TLV includes the second anycast tag.

In some implementations, the first notification message and the second notification message are IGP messages; or the first notification message and the second notification message are BGP messages.

In some implementations, the first forwarding device is a BFER, and the second forwarding device is a transit BFR; or, the first forwarding device is a transit BFR, and the second forwarding device is a BFIR; or, the The first forwarding device and the second forwarding device are adjacent transit BFRs.

In some implementations, the second forwarding device obtains the BFR-ID based on the first parameter set and the third forwarding device. After the first correspondence, the method further includes: the second forwarding device obtains a first BIER message, where the first BIER message includes a first bit string, a label of the second forwarding device, and multicast data message, the first bit string corresponds to one or more of the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

The second forwarding device obtains a second BIER message based on the first BIER message and the first corresponding relationship. The second BIER message includes a second bit string, the first anycast label and the first anycast label. In the multicast data message, the second bit string is obtained based on the F-BM in the first bit string and the first correspondence; the second forwarding device sends the second BIER message .

In some implementations, the second forwarding device sends the second BIER message, including: if the next hop matching the BFR prefix of the first forwarding device is in a fault state, the second forwarding device The device sends the second BIER message to the next hop in the second correspondence relationship that matches the BFR prefix of the third forwarding device; or, if the BFR prefix of the third forwarding device matches the The next hop matching the prefix is in a fault state, and the second forwarding device sends the second BIER message to the next hop matching the BFR prefix of the first forwarding device in the first correspondence relationship. ; Or, if neither the next hop matching the BFR prefix of the first forwarding device nor the next hop matching the BFR prefix of the third forwarding device is in a fault state, the second forwarding The device sends the second forwarding device to the next hop that matches the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the third forwarding device, whichever has the smallest link cost. BIER message; or, if neither the next hop matching the BFR prefix of the first forwarding device nor the next hop matching the BFR prefix of the third forwarding device is in a fault state, the The second forwarding device sends a message to the next hop that matches the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the third forwarding device, whichever has the highest link network quality. The second BIER message; or, if neither the next hop matching the BFR prefix of the first forwarding device nor the next hop matching the BFR prefix of the third forwarding device is faulty status, the second forwarding device sends to any one of the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device. The second BIER message.

In a second aspect, a parameter notification method is provided, including: a first forwarding device in a first site obtains a first parameter set, where the first parameter set includes a first anycast label, a BFR- ID and the BFR prefix of the first forwarding device, the first anycast label is used to identify the first site; the first forwarding device sends the first parameter set to the second forwarding device in the second site .

In some implementations, the first anycast label is a label or an IPv6 destination address.

In some implementations, the first parameter set further includes the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the BIER subdomain in which the first forwarding device is located. identifies one or more of them.

In some implementations, the first forwarding device sending the first parameter set to a second forwarding device in the second site includes: the first forwarding device sending a first notification message to the second forwarding device. , the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the first anycast label.

In some implementations, the first notification message is an IGP message or a BGP message.

In some implementations, the method further includes: the first forwarding device receiving a third parameter set from a third forwarding device in the first site, where the third parameter set includes a first bypass label, the The BFR-ID of the third forwarding device and the BFR prefix of the third forwarding device, the first bypass label is used to identify the third forwarding device; the first forwarding device obtains the third forwarding device based on the third parameter set. Three correspondences, the third correspondence includes the first bypass label, the F-BM matching the BFR-ID of the third forwarding device, and the next hop matching the BFR prefix of the third forwarding device .

In some implementations, after the first forwarding device sends the first parameter set to a second forwarding device in the second site, the method further includes: the first forwarding device receives the first BIER message, and The first BIER message includes a first bit string corresponding to the BFR-ID of the third forwarding device, the first anycast label and a multicast data message; the first forwarding device is based on the first BIER message and the third corresponding relationship to obtain a second BIER message. The second BIER message includes a second bit string, the first bypass label and the multicast data message. The second bit string It is a bit string obtained based on the F-BM in the first bit string and the third corresponding relationship; the first forwarding device sends the second BIER message to the third forwarding device.

In some implementations, the method further includes: the first forwarding device obtaining a fourth parameter set, the fourth parameter set including a second bypass label, the BFR-ID of the first forwarding device and the third A BFR prefix of a forwarding device, the second bypass label is used to identify the first forwarding device; the first forwarding device sends the fourth parameter set to the third forwarding device.

In the third aspect, a corresponding relationship acquisition device is provided, which is located in the second forwarding device in the second site and includes:

A receiving unit configured to receive a first parameter set from a first forwarding device in the first site, where the first parameter set includes a first anycast label, the BFR-ID of the first forwarding device, and the first forwarding device. The BFR prefix of the device, the first anycast label is used to identify the first site;

The receiving unit is further used to receive a second parameter set from a third forwarding device in the first site, the second parameter set including a second anycast label, a BFR-ID of the third forwarding device, and a BFR prefix of the third forwarding device, the second anycast label being used to identify the first site;

A processing unit configured to obtain a first corresponding relationship based on the first parameter set and the BFR-ID of the third forwarding device, where the first corresponding relationship includes the BFR-ID of the first forwarding device and the The forwarding bit mask F-BM matched by the BFR-ID of the third forwarding device, the first anycast label and the next hop matching the BFR prefix of the first forwarding device;

The processing unit is further configured to obtain a second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device, where the second corresponding relationship includes the BFR-ID of the first forwarding device. and the F-BM matching the BFR-ID of the third forwarding device, the second anycast label, and the next hop matching the BFR prefix of the third forwarding device.

In some embodiments, the processing unit is configured to determine that the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag. ; Based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, obtain the F-BM; Based on the F-BM, the first anycast tag and the first The BFR prefix of the forwarding device is used to obtain the first corresponding relationship, which includes the F-BM, the first anycast label, and the BFR prefix of the first forwarding device.

In some embodiments, the processing unit is configured to determine that the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag. ; Based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, obtain the F-BM; Based on the BFR prefix of the first forwarding device, determine the second forwarding device Reach the first outbound interface of the first forwarding device; based on the F-BM, the first anycast label, the BFR prefix of the first forwarding device and the first outbound interface, obtain the first Correspondence, the first correspondence includes the F-BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outbound interface.

In some implementations, the processing unit is configured to determine that both the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag. ; Based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, obtain the F-BM; Based on the F-BM, the second anycast tag and the third The BFR prefix of the forwarding device is used to obtain the second corresponding relationship. The second corresponding relationship includes the F-BM, the second anycast label, and the BFR prefix of the third forwarding device.

In some implementations, the processing unit is configured to determine that both the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag. ; Based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, obtain the F-BM; Based on the BFR prefix of the third forwarding device, determine the second forwarding device Reach the second outbound interface of the third forwarding device; based on the F-BM, the second anycast label, the BFR prefix of the third forwarding device and the second outbound interface, obtain the second Correspondence, the second correspondence includes the F-BM, the second anycast label, the BFR prefix of the third forwarding device, and the second outbound interface.

In some implementations, the first anycast label and the second anycast label are both labels; or the first anycast label and the second anycast label are both IPv6 destination addresses.

In some embodiments, the receiving unit is configured to receive a first notification message from the first forwarding device, the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the The first anycast tag; receiving a second notification message from the first forwarding device in the first site, the second notification message including the BIER information sub-TLV, the BIER information sub-TLV including the second anycast broadcast tag.

In some embodiments, the processing unit is further configured to: obtain a first BIER message, where the first BIER message includes a first bit string, a label of the second forwarding device, and a multicast data message, The first bit string corresponds to one or more of the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device; based on the first BIER message and the first correspondence The relationship is to obtain a second BIER message. The second BIER message includes a second bit string, the first anycast label and the multicast data message. The second bit string is based on the first bit string. The string is obtained from the F-BM in the first corresponding relationship; the device further includes: a sending unit configured to send the second BIER message.

In some embodiments, the sending unit is configured to, if the next hop matching the BFR prefix of the first forwarding device is in a fault state, send a message to the second hop in the second correspondence relationship that matches the BFR prefix of the first forwarding device. The next hop matching the BFR prefix of the third forwarding device sends the second BIER message; or, if the next hop matching the BFR prefix of the third forwarding device is in a fault state, sending the second BIER message to the first corresponding The next hop in the relationship that matches the BFR prefix of the first forwarding device sends the second BIER message; or, if the next hop that matches the BFR prefix of the first forwarding device and None of the next hops matching the BFR prefix of the third forwarding device is in a fault state, and the next hop matching the BFR prefix of the first forwarding device and the third forwarding device The next hop with the smallest link cost that matches the BFR prefix of the device sends the second BIER message; or, if the next hop that matches the BFR prefix of the first forwarding device and the next hop with the smallest link cost, None of the next hops that match the BFR prefix of the third forwarding device are in a fault state, and the next hop that matches the BFR prefix of the first forwarding device and the BFR of the third forwarding device The next hop that matches the prefix and the one with the highest link network quality sends the second BIER message; or, if the next hop that matches the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the first forwarding device, the next hop with the highest link network quality sends the second BIER message. None of the next hops matching the BFR prefix of the third forwarding device are processed. In the fault state, send the second forwarding device to any one of the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device. BIER message.

In a fourth aspect, a parameter notification device is provided, which is located in the first forwarding device in the first site and includes: a processing unit for obtaining a first parameter set, where the first parameter set includes a first anycast tag, all The BFR-ID of the first forwarding device and the BFR prefix of the first forwarding device, the first anycast label is used to identify the first site; the sending unit is used to send a message to the second forwarding device in the second site Send the first set of parameters.

In some embodiments, the sending unit is configured to send a first notification message to the second forwarding device, where the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the third An Anycast tag.

In some implementations, the first advertisement message is an IGP message or a BGP message.

In some implementations, the apparatus further includes: a receiving unit configured to receive a third parameter set from a third forwarding device in the first site, where the third parameter set includes a first bypass label, the third The BFR-ID of the third forwarding device and the BFR prefix of the third forwarding device, the first bypass tag is used to identify the third forwarding device; the processing unit is also used to obtain the The third correspondence relationship includes the first bypass tag, the F-BM matching the BFR-ID of the third forwarding device, and the next F-BM matching the BFR prefix of the third forwarding device. Jump.

In some embodiments, the receiving unit is further configured to receive a first BIER message, where the first BIER message includes a first bit string corresponding to the BFR-ID of the third forwarding device, the first anycast label and multicast data message; the processing unit is also configured to obtain a second BIER message based on the first BIER message and the third corresponding relationship, where the second BIER message includes a second A bit string, the first bypass label and the multicast data message, the second bit string is a bit string obtained based on the F-BM in the first bit string and the third correspondence relationship; The sending unit is also configured to send the second BIER message to the third forwarding device.

In some embodiments, the processing unit is further configured to obtain a fourth parameter set, the fourth parameter set including a second bypass label, the BFR-ID of the first forwarding device, and the BFR-ID of the first forwarding device. BFR prefix, the second bypass label is used to identify the first forwarding device; the sending unit is also used to send the fourth parameter set to the third forwarding device.

In a fifth aspect, a forwarding device is provided. The forwarding device includes a processor and a network interface. The forwarding device executes the above first aspect or any one of the first aspects through the processor and the network interface. Select the method provided by the method.

In a sixth aspect, a forwarding device is provided. The forwarding device includes a processor and a network interface. The forwarding device performs the above second aspect or any one of the second aspects through the processor and the network interface. Optional methods provided.

A seventh aspect provides a network system, which includes the device in the third aspect and the device in the fourth aspect.

An eighth aspect provides a network system, which includes the device of the fifth aspect and the device of the sixth aspect.

In a ninth aspect, a computer-readable storage medium is provided. At least one instruction is stored in the storage medium. When the instruction is run on a computer, it causes the computer to execute the above-mentioned first aspect or any one of the optional first aspects. method provided.

In a tenth aspect, a computer-readable storage medium is provided, at least one instruction is stored in the storage medium, and the instruction is stored in the computer readable storage medium. When running on a computer, the computer is caused to execute the method provided by the above second aspect or any of the optional methods of the second aspect.

In an eleventh aspect, a computer program product is provided. The computer program product includes one or more computer program instructions. When the computer program instructions are loaded and run by a computer, they cause the computer to execute the above first aspect or Methods provided by any optional method in the first aspect.

In a twelfth aspect, a computer program product is provided. The computer program product includes one or more computer program instructions. When the computer program instructions are loaded and run by a computer, they cause the computer to execute the above second aspect or The method provided by any optional method in the second aspect.

In a thirteenth aspect, a chip is provided. The chip includes programmable logic circuits and/or program instructions. When the chip is run, it is used to implement the method provided by the above-mentioned first aspect or any alternative method of the first aspect. .

In a fourteenth aspect, a chip is provided. The chip includes programmable logic circuits and/or program instructions. When the chip is run, it is used to implement the method provided in the above-mentioned second aspect or any of the optional modes of the second aspect. .

Description of the drawings

Figure 1 is a schematic diagram of a networking scenario provided by an embodiment of the present application;

Figure 2 is a schematic diagram of another networking scenario provided by an embodiment of the present application;

Figure 3 is a schematic diagram of yet another networking scenario provided by an embodiment of the present application;

Figure 4 is a flow chart of a multicast configuration method provided by an embodiment of the present application;

Figure 5 is a flow chart of a method for processing multicast data packets provided by an embodiment of the present application;

Figure 6 is a flow chart of a method for obtaining a correspondence relationship provided by an embodiment of the present application;

Figure 7 is a flow chart of a data packet processing method provided by an embodiment of the present application;

Figure 8 is a flow chart of another data packet processing method provided by an embodiment of the present application;

Figure 9 is a schematic diagram of the format of the BIER information sub-TLV provided by the embodiment of the present application;

Figure 10 is a schematic diagram of the format of BIER-MPLS encapsulated sub-sub-TLV provided by the embodiment of the present application;

Figure 11 is a schematic diagram of the format of a sub-sub-TLV carrying anycast label provided by the embodiment of the present application;

Figure 12 is a schematic diagram of a parameter configuration scenario provided by an embodiment of the present application;

Figure 13 is a schematic diagram of another parameter configuration scenario provided by the embodiment of the present application;

Figure 14 is a schematic diagram of another parameter configuration scenario provided by the embodiment of the present application;

Figure 15 is a schematic diagram of another parameter configuration scenario provided by the embodiment of the present application;

Figure 16 is a schematic diagram of a message format provided by an embodiment of the present application;

Figure 17 is a schematic diagram of another message format provided by the embodiment of the present application;

Figure 18 is a schematic diagram of yet another message format provided by an embodiment of the present application;

Figure 19 is a schematic diagram of a parameter configuration scenario provided by an embodiment of the present application;

Figure 20 is a schematic diagram of another parameter configuration scenario provided by the embodiment of the present application;

Figure 21 is a schematic diagram of another parameter configuration scenario provided by the embodiment of the present application;

FIG22 is a schematic diagram of a scenario of another parameter configuration provided in an embodiment of the present application;

Figure 23 is a schematic diagram of a network deployment scenario provided by an embodiment of this application;

Figure 24 is a schematic diagram of a message format provided by an embodiment of the present application;

Figure 25 is a schematic diagram of another message format provided by the embodiment of the present application;

Figure 26 is a schematic diagram of yet another message format provided by an embodiment of the present application;

Figure 27 is a schematic diagram of a network deployment scenario provided by an embodiment of the present application;

Figure 28 is a schematic diagram of another network deployment scenario provided by an embodiment of the present application;

Figure 29 is a schematic diagram of another network deployment scenario provided by the embodiment of the present application;

Figure 30 is a schematic diagram of yet another network deployment scenario provided by an embodiment of the present application;

Figure 31 is a schematic diagram of another network deployment scenario provided by an embodiment of the present application;

Figure 32 is a schematic diagram of yet another network deployment scenario provided by an embodiment of the present application;

Figure 33 is a schematic diagram of a message format provided by an embodiment of the present application;

Figure 34 is a schematic diagram of another message format provided by the embodiment of the present application;

Figure 35 is a schematic diagram of yet another network deployment scenario provided by the embodiment of the present application;

Figure 36 is a schematic diagram of another network deployment scenario provided by the embodiment of the present application;

Figure 37 is a schematic diagram of yet another network deployment scenario provided by the embodiment of the present application;

Figure 38 is a schematic diagram of a message format provided by an embodiment of the present application;

Figure 39 is a schematic diagram of another message format provided by the embodiment of the present application;

Figure 40 is a schematic diagram of a network deployment scenario provided by an embodiment of the present application;

Figure 41 is a schematic diagram of another network deployment scenario provided by the embodiment of the present application;

Figure 42 is a schematic structural diagram of a device for obtaining a correspondence relationship provided by an embodiment of the present application;

Figure 43 is a schematic structural diagram of a parameter notification device provided by an embodiment of the present application;

Figure 44 is a schematic structural diagram of a forwarding device provided by an embodiment of the present application.

Detailed ways

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

Some terms and concepts involved in the embodiments of this application are explained below.

(1)site

A site is a logical area, and a site includes one or more forwarding devices with IP connectivity. For example, a site includes two forwarding devices.

(2) Forwarding equipment

A forwarding device refers to any device with routing and forwarding functions. For example, forwarding devices include but are not limited to routers, switches, firewalls, servers, or hosts.

(3) bit indexed explicit replication (BIER)

BIER is a new type of multicast forwarding technology that encapsulates the set of destination nodes for multicast messages in the form of bit strings and sends them in the header of the message. This eliminates the need for intermediate nodes in the network to sense multicast services and maintain multicast flows. state. The effects of BIER include but are not limited to: First, it has good multicast service scalability; BIFT established using BIER technology on BFR is a public forwarding table independent of specific multicast services, so that intermediate nodes in the network do not need to be aware of multicast services. , there is no need to maintain the multicast flow status of specific multicast services. Both public network multicast and private network multicast packets can be forwarded through BIFT, which has good multicast service scalability. Second, simplify business deployment and operation and maintenance. Since intermediate nodes in the network are not aware of multicast services, the deployment of multicast services usually does not involve intermediate nodes. Changes in multicast services have little impact on intermediate nodes, simplifying network deployment and operation and maintenance. Third, it is conducive to the evolution of software-defined network (SDN) architecture networks. Specifically, deploying multicast services does not require operating network intermediate nodes. You only need to add a BIER header to multicast packets at the entry node to indicate subsequent multicast replication. The BIER header carries a bit string that identifies the multicast outlet node, and the intermediate node implements multicast replication based on the bit string. control and forwarding, thus conducive to the evolution of SDN architecture networks.

(4)BIER network

A BIER network refers to a logical area that supports BIER forwarding. A BIER network includes multiple BFRs. Optionally, a BIER network is a BIER domain, or a BIER network is a BIER subdomain.

(5)BIER subdomain (BIER sub-domain).

A BIER domain can be divided into one or more BIER subdomains, which can also be referred to as SD. Each BIER subdomain is identified by a unique sub-domain ID.

(6) bit-forwarding router (BFR)

BFR refers to a device that supports BIER forwarding. BFR product forms include but are not limited to routers, switches, firewalls or other network equipment. BFR is divided into bit forwarding ingress router (BFIR), intermediate BFR (transit BFR) and bit forwarding egress router (BFER).

(7)BFIR

BFIR is the node through which multicast data flows enter the BIER network. BFIR is used to BIER encapsulate multicast data packets entering the BIER network to obtain BIER packets containing multicast data packets and BIER headers.

(8)transit BFR

transit BFR is an intermediate node for forwarding multicast data packets in the BIER network. It is used to forward BIER packets based on bit strings. transit BFR is an optional device deployed in the BIER network. In some embodiments, BFIR and BFER are deployed in the BIER network without transit BFR. For example, BFIR and BFER are directly connected physically; another example is that BFIR and BFER are directly connected, and BFER is the next hop of BFIR; another example is that BFIR and BFER are connected through one or more hops that do not support BIER, and BFIR sends BIER messages. Finally, the BIER packet passes through the MPLS encapsulation or IPv6 unicast route in the outer layer of the BIER header and passes through the node that does not support BIER to reach the BFER.

In the embodiment of deploying transit BFR, the number of transit BFR deployed in a BIER network includes multiple situations. Two situations are given as examples below. In some embodiments, a transit BFR is deployed in a BIER network. The transit BFR is located between the BFIR and the BFER in the BIER forwarding path. BIER messages are forwarded from the BFIR to the BFER via the transit BFR. In other embodiments, two or more transit BFRs are deployed in a BIER network. There is an up-and-down hop relationship between different transit BFRs. BIER messages are forwarded from BFIR to another transit BFR via one transit BFR. Then forward it from another transit BFR to BFER. For example, if BFIR, transit BFR 1, transit BFR 2 and BFER are deployed in the BIER network, the forwarding path of BIER packets is BFIR→transit BFR 1→transit BFR 2→BFER.

transit BFR is an optional device deployed in the BIER network. In some embodiments, BFIR and BFER are deployed in the BIER network without transit BFR. For example, BFIR and BFER are physically directly connected, and BFER is the next hop of BFIR; another example, BFIR and BFER are connected through one or more hops that support BIER; another example, BFIR and BFER are connected through one or more hops that do not support BIER. The nodes are connected. After BFIR sends a BIER message, the BIER message passes through the MPLS encapsulation or IPv6 unicast route in the outer layer of the BIER header and reaches BFER through the node that does not support BIER.

In the embodiment of deploying transit BFR, the number of transit BFR deployed in a BIER network includes multiple situations. Two situations are given as examples below.

In some embodiments, a transit BFR is deployed in a BIER network. The transit BFR is located between the BFIR and the BFER in the BIER forwarding path, and the BIER message is forwarded from the BFIR to the BFER via the transit BFR.

In other embodiments, two or more transit BFRs are deployed in a BIER network. There is an up-and-down hop relationship between different transit BFRs. BIER messages are forwarded from BFIR to another transit BFR via one transit BFR. Then from another transit BFR forwards to BFER. For example, if BFIR, transit BFR 1, transit BFR 2, and BFER are deployed in the BIER network, the forwarding path of BIER packets is BFIR→transit BFR 1→transit BFR 2→BFER.

(9)BFER

BFER is the node through which multicast data flows out of the BIER network. It is used to decapsulate BIER packets and forward the obtained multicast data packets to multicast receivers.

(10)Edge BFR

Edge BFR refers to the BFR located at the edge of the BIER network. Edge BFR is the collective name of BFIR and BFER.

(11) bit forwarding router identifier (BFR-ID)

Regarding the role of BFR-ID, BFR-ID is used to identify the BFR located at the edge of the BIER network in a BIER network (such as a BIER subdomain or a BIER domain).

For the form of BFR-ID, BFR-ID is usually an integer, for example, a positive integer in the range of 1 to 65535.

Regarding the relationship between BFR-ID and bit string, in some embodiments, one BFR-ID corresponds to one bit in the bit string. For example, BFR-ID is 1, which corresponds to the rightmost bit (or the lowest bit) in the bit string; BFR-ID is 2, which corresponds to the second bit from right to left (or the second lowest bit) in the bit string. ; By analogy, BFR-ID is i, corresponding to the i-th bit from right to left in the bit string, where i is a positive integer.

Regarding the meaning of BFR-ID, if the bit string carried by a message contains the BFR-ID of a device, or the bit position corresponding to the BFR-ID of the device is set, it means that the device is the destination BFER of the message.

(12)BFR prefix(BFR prefix)

BFR prefix refers to an IP address of BFR. Optionally, the BFR prefix is the IP address of a loopback interface on the BFR. For example, the BFR prefix is a reachable IP address in the BIER network. For example, BFR prefix is a 32-bit IPv4 address; another example, BFR prefix is a 128-bit IPv6 address. Optionally, in the BIERv4 scenario, use an IPv4 address of the device as the BFR prefix; in the BIERv6 scenario, use an IPv6 address of the device as the BFR prefix.

(13) Set Identifier (SI)

SI refers to the identifier of the set to which the BFR-ID belongs. The form of SI is usually one or a series of numbers. For example, a BIER network includes set 0 and set 1. Set 0 includes BFRs with BFR IDs from 1 to 256, and set 1 includes BFRs with BFR IDs from 257 to 512. Then each BFR in the BFRs with BFR IDs from 1 to 256 The SI is 0, and the SI of each BFR in BFR IDs 257 to 512 is 1.

(14)SI maximum value (max SI, also called max-SI, MAX-SI or MAX SI)

max-SI refers to the maximum value of the set identifier (SI).

(15) bit string

The bit string is used to identify the destination BFER set of the BIER message. The bit string starts from the lowest bit (that is, the first bit from the right), and each bit corresponds to a BFR ID. Bit position 1 indicates that the BFER identified by the BFR ID corresponding to this bit is the destination BFER for multicast data packet forwarding.

(16) Bit string length (BS length, BSL)

BSL refers to the length of the bit string. For example, if the BSL is 64, it means that the length of the bit string is 64 bits.

(17) bit index routing table (BIRT)

BIRT is used to indicate the correspondence between the BFR prefix of a BFER in a BIER network, the BFR-ID of the BFER, and the next hop to the BFER on the forwarding path. For the detailed definition of BIRT, please refer to the introduction in Section 6.3 of RFC 8279.

(18) bit index forwarding table (BIFT)

BIFT is a forwarding table based on BIRT. BIFT is used to represent each BFER node that can be reached through BFR neighbors, including Nbr (BFR Neighbor, BFR neighbor) and forwarding bit mask (forwarding bit mask, F-BM). Each BIFT is usually determined by a triplet (BSL, SD, SI). For example, BIFT is generated by BFR by merging different entries in BIRT entries that pass through the same neighbor. Optionally, each BIFT entry includes a BFR neighbor and the corresponding F-BM.

(19) Bit Indexed Forwarding Table Identification (BIFT-ID)

BIFT-ID is used to identify a BIFT. BIFT ID is usually determined based on three parameters: BSL, SD and SI. For example, BIFT-ID is obtained by splicing three parameters: BSL, SD and SI. For another example, BIFT-ID is the hash value obtained by hashing the three parameters BSL, SD and SI.

(20)BFR neighbor (BFR Nbr)

The BFR neighbor represents the next hop BFR. Optionally, the BFR neighbor is represented by the BFR prefix of the next hop BFR.

(21) Forwarding bit mask (F-BM)

F-BM is used to indicate the set of BFERs in the BIER network that can be reached through the BFR neighbor when the BFR copies and sends multicast data packets to the BFR neighbor. F-BM is, for example, BFR obtained by ORing the bit strings of all BFERs reachable by the BFR neighbor. FBM is represented by a bit string, and the length of the bit string used by FBM and packet forwarding is the same. For example, the length of the bit string carried in the message is 256 bits, and the length of the F-BM is also 256 bits. During the message forwarding process, the bit string carried in the message will perform an AND operation with the F-BM.

(22)End.BIER SID

End.BIER SID is the IPv6 address of BFR and is also a SID in SRv6. End.BIER SID is usually carried in the destination address field of the IPv6 basic header. End.BIER SID usually includes a locator field and a function field, and optionally also includes an argument field. The locator field occupies the high-order bits of the SID. The locator field is used to carry the location information of the device to guide packet forwarding to the device. The locator field usually contains the block field and the node ID field. The block field is used to indicate the IP address block to which the SID belongs. This IP address block is generally allocated to a subnet by the operator. The node ID field is used to carry the identification of the device, usually used to distinguish different devices within a subnet. The function field is used to carry the function identifier, and the function identifier is used to indicate that multicast packets are forwarded in BIER mode. The form of the function identifier is, for example, a string. The function identifier has a binding relationship with the BIER forwarding instruction saved on the device. Therefore, the forwarding device reads the End.BIER SID in the destination address field. According to the function in the End.BIER SID If the command to perform BIER forwarding is matched, the forwarding device will forward the multicast data packet according to the BIER method, that is, copy and forward the packet based on the bit string in the packet header and BIFT. The function field is located after the locator field. The parameter field is an optional field in the SID. The parameter field is used to carry function-related parameters.

Through End.BIER SID, the reachability of IPv6 unicast routing can be well utilized to span IPv6 nodes that do not support BIER. For example, in a BIERv6 scenario, the End.BIER SID is carried in the destination address field in the data packet header to indicate that BIERv6 forwarding processing needs to be performed on this node, and the forwarding plane will continue to process the BIERv6 extension header. After the forwarding device determines the BFR neighbor by comparing the bit string with the F-BM, the destination address of the outer IPv6 message needs to be replaced with the End.BIER SID of the next hop node, and the BIERv6 message is copied to the End.BIER SID. BFR. When the device does not support BIER, the End.BIER SID can be used as a normal IPv6 address and forwarded using the unicast function.

(23)BIER-MPLS label

BIER-MPLS label is an MPLS label and also the index of BIFT on BFR. The BIER-MPLS label is usually carried in the BIFT-ID field in the BIER packet header. BIER-MPLS label is usually a label assigned according to <Sub-domain, SI, BSL>. For example, When a BFR receives a BIER message, it first parses the BIER-MPLS Label in the message header and uses the Label to index into the corresponding local BIFT table. Because there may be multiple <sub-domain, SI, BSL> on one BFR, different forwarding tables will be generated. The mapping relationship between different <Sub-domain, SI, BSL> and BIER-MPLS Label is one-to-one correspondence. Through the BIER-MPLS Label field in the current packet header, the corresponding BIER forwarding table can be indexed, and compared with the F-BM in the forwarding table one by one, the BFR-neighbors can be calculated. Based on the calculated different BFR-neighbors, Replace the BIER-MPLS Label in the BIER packet header with a different label, and then forward the packet.

(24)Multicast group

A multicast group refers to a collection identified by a multicast address. When a host (or other device that needs to receive multicast data packets) joins a multicast group, it becomes a member of the multicast group and can identify and receive multicast data sent to the multicast group.

(25)Multicast source

The sender of multicast data packets is called a "multicast source". One multicast source can send data to multiple multicast groups at the same time, and multiple multicast sources can also send packets to one multicast group at the same time. Multicast sources usually do not need to join a multicast group.

The application scenarios of the embodiments of this application are illustrated below with examples.

The embodiment of this application is applied to the scenario where multicast BIER is configured, for example, it is applied to the scenario where there are multiple devices in a site, and each device is configured with multicast BIER. According to some embodiments of the present application, by configuring anycast labels on multiple devices in the same site, the anycast label is used to identify the site to which the device belongs. Therefore, each device uses anycast label, BFR-ID and BFR prefix. After the parameters are announced together, the device that receives the parameters will reflect the BFR-IDs of multiple forwarding devices in the same site to the F-BM based on the anycast label when generating the correspondence between the devices arriving at the site. In the same entry, when a data packet containing the bit string corresponding to the BFR-ID of any device in the site is received, it can be matched to the F-BM based on the bit string, and forwarded to the next hop corresponding to the F-BM. message. If a node failure or link failure occurs on one of the devices in the site, it can also match the corresponding F-BM to another device and forward the packets, thereby avoiding traffic interruption and realizing rapid switchover and traffic protection in fault scenarios.

The embodiments of this application are applicable to many networking scenarios. The following is an example of three networking scenarios.

Networking Scenario 1: Deploy root nodes and leaf nodes, but do not deploy intermediate nodes.

Figure 1 is a schematic diagram of a networking scenario provided by an embodiment of the present application. In the scenario shown in Figure 1, the BIER network includes a forwarding device 110, a forwarding device 121 and a forwarding device 122. Forwarding device 110 is located within site A. The forwarding device 121 and the forwarding device 122 are located in site B. Forwarding device 110 communicates with the multicast source. From a multicast perspective, forwarding device 110 is the root node. From a BIER perspective, the forwarding device 110 is a BFIR in the BIER network. Forwarding device 121 communicates with multicast receiver 1. From a multicast perspective, the forwarding device 121 is a leaf node. From a BIER perspective, the forwarding device 121 is a BFER in the BIER network. Forwarding device 122 communicates with multicast receiver 2. From a multicast perspective, the forwarding device 122 is a leaf node. From a BIER perspective, the forwarding device 122 is a BFER in the BIER network. Forwarding device 110 communicates with one or more of forwarding device 121 and forwarding device 122 . In some embodiments, the forwarding device 110 communicates with the forwarding device 121, and the forwarding device 110 communicates with the forwarding device 122. That is, the forwarding device 110 can communicate with two forwarding devices in site B. In other embodiments, the forwarding device 110 communicates with the forwarding device 121, but the forwarding device 110 and the forwarding device 122 cannot communicate, or the forwarding device 110 communicates with the forwarding device 122, but the forwarding device 110 and the forwarding device 121 cannot communicate, that is, Forwarding device 110 communicates with a forwarding device within site B.

Networking scenario 2: Deploy root nodes, leaf nodes and one-hop intermediate nodes.

Figure 2 is a schematic diagram of another networking scenario provided by the embodiment of the present application. The scenario shown in Figure 2 is based on the scenario shown in Figure 1 and further deploys a forwarding device 131. The forwarding device 131 is located within site C. Forwarding device 131 communicates with forwarding device 110 . Forwarding device 131 communicates with forwarding device 121 and forwarding device 122 . From a multicast perspective, the forwarding device 131 is an intermediate node. From BIER From this perspective, the forwarding device 131 is the transit BFR in the BIER network.

Networking scenario three: deploy root nodes, leaf nodes and multi-hop intermediate nodes.

Figure 3 is a schematic diagram of another networking scenario provided by the embodiment of the present application. The scenario shown in Figure 3 is based on the scenario shown in Figure 2 and further deploys a forwarding device 141. The forwarding device 141 is located within site D. Forwarding device 141 communicates with forwarding device 110 . The forwarding device 141 and the forwarding device 131 are connected through a network. From the perspective of multicast, forwarding device 141 and forwarding device 131 are adjacent two-hop intermediate nodes in the forwarding path. The forwarding device 141 is an upstream node of the forwarding device 131 , and the forwarding device 131 is a downstream node of the forwarding device 141 . From the perspective of BIER, forwarding device 141 and forwarding device 131 are adjacent two-hop transit BFRs.

The communication relationship between the various devices described above is represented by the lines between the devices in the figure. The communication relationship between the devices includes but is not limited to physical direct connection, connection through one or more layer 2 switches, connection through IP overlay tunnel, and connection through label switching path (LSP). Physical direct connection includes but is not limited to connection through cable, optical fiber or other transmission media. Connection through label switching path is achieved through MPLS, for example, in Figure 2, forwarding device 131 and forwarding device 121 can be connected through a label switching path, forwarding device 131 and forwarding device 121 are two endpoints of the label switching path, and one or more label switching routers (LSRs) are passed between forwarding device 131 and forwarding device 121.

The following is an example of the method flow of the embodiment of the present application.

Some embodiments of the present application involve multiple site scenarios. In order to distinguish different sites, "first site" and "second site" are used to describe different sites.

Some embodiments of the present application involve interaction between multiple forwarding devices. In order to distinguish different forwarding devices, "first forwarding device", "second forwarding device" and "third forwarding device" are used to distinguish and describe multiple different forwarding devices. The first forwarding device and the third forwarding device are both devices in the first site. The second forwarding device is a device in the second site. The roles of the first forwarding device, the second forwarding device, and the third forwarding device include multiple situations, which are illustrated below with examples from Situation 1 to Situation 3.

Case 1: The first forwarding device is BFER, the third forwarding device is BFER, and the second forwarding device is transit BFR. That is, the first forwarding device and the third forwarding device are both leaf nodes, and the second forwarding device is an intermediate node. For example, looking at the scenario shown in Figure 2, the first forwarding device is the forwarding device 121 in Figure 2, the third forwarding device is the forwarding device 122 in Figure 2, and the second forwarding device is the forwarding device 131 in Figure 2.

Case 2: The first forwarding device is transit BFR, the second forwarding device is BFIR, and the third forwarding device is transit BFR. That is, the first forwarding device and the third forwarding device are both intermediate nodes, and the second forwarding device is the root node. For example, looking at the scenario shown in Figure 2, the first forwarding device is the forwarding device 131 in Figure 2, the third forwarding device is the forwarding device 132 in Figure 2, and the second forwarding device is the forwarding device 110 in Figure 2.

Case 3: The first forwarding device and the second forwarding device are adjacent transit BFRs. For example, the first forwarding device is the transit BFR located downstream of the second forwarding device on the BIER forwarding path, and the second forwarding device is the transit BFR located upstream of the first forwarding device on the BIER forwarding path. For example, looking at the scenario shown in Figure 3, the first forwarding device is the forwarding device 131 in Figure 3, the third forwarding device is the forwarding device 132 in Figure 3, and the second forwarding device is the forwarding device 141 in Figure 2.

In some embodiments of the present application, an anycast label is configured on the forwarding device, and the site to which the forwarding device belongs is identified through the anycast label. In a scenario where multiple forwarding devices exist in a site, anycast labels configured on different forwarding devices in the site identify the same site. The expression form of anycast tag includes many possible forms. The following three forms are given as examples.

Form 1 of anycast label, IPv6 destination address

For example, the anycast label is End.BIER SID, multicast policy reserved address (MPRA) or IPv6 link-local address. For example, configure the End.BIER SID of the first forwarding device in the first site As the first anycast label, configure the End.BIER SID of the third forwarding device in the first site as the second anycast label. By using the End.BIER SID as the anycast tag, on the one hand, it is compatible with scenarios where BIER is run on IPv6 networks, such as BIERv6 scenarios. On the other hand, the anycast label can not only identify the site, but also instruct the device to forward multicast packets in the BIER manner; on the other hand, because the End.BIER SID is in the form of an IPv6 address, the links between sites pass through When there is an IPv6 node that does not support BIER in one or more hops, using the reachability of IPv6 unicast routing, the data packet can cross the IPv6 node that does not support BIER and be transmitted to another site, thus making it compatible between sites through the IPv6 node that does not support BIER. Networking scenario of IPv6 nodes. By using MPRA as anycast label, it can be compatible with G-BIER encapsulation method. By using the link-local address as the anycast label, it can be compatible with the BIERin6 encapsulation method.

Anycast tag form 2. Tag

For example, anycast labels are labels assigned to devices in a site based on BSL, SD, and SI. Different sites have different values for the anycast tag. If different BFRs in the same site are configured with different BSL, SD, and SI, the values of anycast labels corresponding to different BFRs in the same site are different. Only when each BFR in the same site has the same BSL, SD, and SI, each BFR in the same site will have the same anycast label. Anycast labels can be MPLS labels in MPLS scenarios, or non-MPLS labels allocated in other encapsulation scenarios besides MPLS.

The third form of anycast tag is a number or a series of numbers assigned according to the number of sites in the BIER network.

For example, the network administrator or controller assigns a number or a series of numbers as anycast tags based on the number of sites in the BIER network. For example, the controller assigns anycast tags to each site in order from small to large. For example, if the BIER network contains two sites, site A and site B, site A is assigned "1" as the anycast label of the equipment in site A, and site B is assigned "2" as the anycast label of the equipment in site B. Label; for another example, site A is assigned "111" as the anycast label of the equipment in site A, and site B is assigned "222" as the anycast label of the equipment in site B.

The three forms described above are only examples of the forms of anycast tags, and anycast tags may also have other forms. For example, the anycast label is an IPv6 address in a non-SID format, or the anycast label is an IPv4 address, or the anycast label is an MPLS label in a non-BIER-MPLS label format. This embodiment does not limit the format of the anycast label.

In some embodiments, the anycast label of each forwarding device within the same site is configured in the same form and with the same value. For example, a first anycast label is configured for the first forwarding device in the first site, and a second anycast label is configured for the third forwarding device in the first site. The second anycast tag and the first anycast tag have the same value. For example, the second anycast tag and the first anycast tag are both in the form of End.BIER SID. The value of the second anycast tag is 1::1, and the value of the first anycast tag is also 1::1. For another example, the second anycast label and the first anycast label are both MPLS labels. The value of the second anycast label is 10, and the value of the first anycast label is also 10.

Since the anycast label of each forwarding device in the same site is configured with the same value, after each forwarding device in the site advertises the parameter set containing the anycast label, the receiving end of the parameter set carries the parameter set based on the received multiple parameters. If the same anycast label is found, it can be determined that the devices from multiple parameter sets belong to the same site, and then it is determined to merge the BFR-IDs included in multiple parameter sets into the same F-BM, with low implementation complexity. .

The anycast label described above can be reflected in the correspondence obtained by the forwarding device. The correspondence can be used to forward data packets. Optionally, the forwarding device saves the obtained correspondence in the form of table entries and uses the obtained correspondence by looking up the table. For example, a correspondence is a row of table entries or a collection of multiple rows of table entries in a table on the forwarding device. The tables on the forwarding device are usually divided into a routing information base (Routing information Base, RIB) and a forwarding information base (forwarding information base, FIB). The specific form of the correspondence can be a table entry in the RIB table or a table entry in the FIB table.

The anycast labels described above can be flooded in the BIER network through any dynamic routing protocol, so that each BFR in the BIER network receives anycast labels from other BFRs. In some embodiments, anycast labels are advertised through IGP messages, such as IS-IS messages Or OSPF packets advertise anycast labels. In other embodiments, anycast labels are advertised through BGP messages.

In some embodiments, the anycast label and BFR prefix described above are carried in one advertisement message and thus flooded together in the BIER network. For example, the forwarding device sends a notification message. The notification message includes a prefix TLV, the prefix TLV includes the BFR prefix, and the sub-TLV of the prefix TLV includes the anycast label. For another example, the forwarding device sends a notification message. The notification message includes a network reachability information (NLRI) field and a path attribute field. The NLRI field includes the BFR prefix, and the path attribute field includes the anycast label.

In some embodiments, the anycast tag described above is flooded not only with the BFR prefix, but also with other parameters of the BIER. The BIER parameters flooded together with the anycast label include, but are not limited to, one or more of the BFR-ID, the bit string length BSL, the set identifier SI, and the identifier of the BIER subdomain. In some embodiments, the three parameters of anycast label, BFR-ID, and BFR prefix are advertised through the same message; for example, the forwarding device sends an announcement message, and the announcement message includes anycast label, BFR-ID, and BFR prefix; in other embodiments, the forwarding device advertises the anycast label and BFR prefix through one message, and the BFR prefix and BFR-ID through another message.

The specific fields where the anycast label is located in the notification message include various situations. Optionally, use the BIER information sub-TLV to advertise the anycast label. Optionally, the anycast label is advertised using a sub-sub-TLV in the BIER information sub-TLV. For example, the forwarding device sends a notification message. The notification message includes a prefix TLV. The prefix TLV includes a BIER information sub-TLV. The BIER information sub-TLV includes a sub-sub-TLV. The sub-sub-TLV includes an anycast label.

Figure 4 is a flow chart of a multicast configuration method provided by an embodiment of the present application. The method shown in Figure 4 includes the following steps S201 to S208.

Step S201: The first forwarding device in the first site obtains the first parameter set.

The first parameter set includes the first anycast label, the BFR-ID of the first forwarding device, and the BFR prefix of the first forwarding device. The first anycast tag is used to identify the first site. In some embodiments, the first anycast label is the IPv6 address of the first forwarding device, for example, the End.BIER SID of the first forwarding device. In some embodiments, the first anycast label is a label, such as a BIER-MPLS label of the first forwarding device. In some embodiments, the first parameter set further includes one or more of the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the identifier of the BIER subdomain where the first forwarding device is located. .

Step S202: The first forwarding device sends a first parameter set to a second forwarding device in a second site.

In some embodiments, the first forwarding device sends the first parameter set by flooding. For example, the first forwarding device and the second forwarding device are in the same BIER network. The first forwarding device in the BIER network floods the first parameter set in the BIER network, so that the second forwarding device in the BIER network can receive the first parameter set.

In some embodiments, the first forwarding device generates the first notification message, and the first forwarding device sends the first notification message to the second forwarding device. The first advertisement message includes the first anycast label. In some embodiments, the first advertisement message also includes other parameters other than the first anycast label in the first parameter set. For example, the first notification message includes the BFR-ID of the first forwarding device, the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the identifier of the BIER subdomain where the first forwarding device is located. one or more of.

Regarding the field carrying the first anycast label, in some embodiments, the first advertisement message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the first anycast label. In a possible implementation, the BIER information sub-TLV includes the BFR-ID of the first forwarding device, the identifier of the BIER subdomain where the first forwarding device is located, and a sub-sub-TLV. The BIER information sub-TLV includes the sub- The sub-TLV includes the first anycast label, the BSL of the first forwarding device, and the set identity SI to which the first forwarding device belongs.

Regarding the message type used to send the first parameter set, in some embodiments, the first advertisement message is an IGP message. For example, the first advertisement message is an intermediate system to intermediate system (IS-IS) message or an (open shortest path first, OSPF) message. In other embodiments, the first advertisement message is a border gateway protocol (BGP) message. For example, the first advertisement message is a border gateway protocol ethernet virtual private network (BGP EVPN) message.

How the first forwarding device obtains the first parameter set includes multiple implementation methods. In a possible implementation, the first parameter set is obtained through static configuration. For example, the network administrator performs a configuration operation on the first forwarding device through a command line or a web interface, and inputs the above first parameter set. The first forwarding device responds to the configuration operation of the network administrator and obtains the first parameter set input by the network administrator. In another possible implementation, the first parameter set is obtained by being issued by the controller. For example, the controller allocates a first parameter set to the first forwarding device. The controller sends the first parameter set to the first forwarding device. The first forwarding device receives the first parameter set sent by the controller.

Step S203: The second forwarding device in the second site receives the first parameter set from the first forwarding device in the first site.

For example, the second forwarding device receives a first notification message from the first forwarding device, the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes a first parameter set. The second forwarding device obtains the first parameter set from the BIER information sub-TLV in the first advertisement message.

Step S204: The third forwarding device in the first site obtains the second parameter set.

The second parameter set includes the second anycast label, the BFR-ID of the third forwarding device, and the BFR prefix of the third forwarding device. The second anycast tag is used to identify the first site. Since both the second anycast label and the first anycast label identify the first site, the receiving end of the parameter set can determine the third forwarding device and the first forwarding device based on the second anycast label and the first anycast label. The devices belong to the same site.

In some embodiments, the second anycast label is the End.BIER SID or MPLS label.

In some embodiments, the second parameter set further includes one or more of the bit string length BSL of the third forwarding device, the set identifier SI to which the third forwarding device belongs, and the identifier of the BIER subdomain where the third forwarding device is located. .

Step S205: The third forwarding device sends the second parameter set to the second forwarding device in the second site.

In some embodiments, the third forwarding device generates a second notification message, the third forwarding device sends the second notification message to the second forwarding device, and the second notification message includes the second parameter set.

In some embodiments, the second advertisement message includes a BIER information sub-TLV, and the BIER information sub-TLV includes a second anycast label.

In some embodiments, the second advertisement message is an IGP message. For example, the second advertisement message is an IS-IS message or an OSPF message. In other embodiments, the first advertisement message is a BGP message. For example, the first advertisement message is a BGP EVPN message.

Regarding the field carrying the second anycast label, in some embodiments, the second advertisement message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the second anycast label. In a possible implementation, the BIER information sub-TLV includes the BFR-ID of the second forwarding device and the identification of the BIER subdomain where the second forwarding device is located and a sub-sub-TLV, and the sub-sub-TLV includes the second forwarding device. The anycast label, the BSL of the second forwarding device, and the set identifier SI to which the second forwarding device belongs.

Step S206: The second forwarding device receives the second parameter set from the third forwarding device in the first site.

For example, the second forwarding device receives the second advertisement message from the third forwarding device in the first site. The second notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes a second parameter set. The second forwarding device obtains the second parameter set from the BIER information sub-TLV in the second advertisement message.

Step S207: The second forwarding device obtains the first correspondence based on the first parameter set and the BFR-ID of the third forwarding device.

The first corresponding relationship includes the F-BM matching the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, the first anycast label, and the next hop matching the BFR prefix of the first forwarding device. The first corresponding relationship can be realized through one table entry or through multiple related table entries. The following is an example of implementation method 1 and implementation method 2.

Implementation method 1: The first corresponding relationship is a table item.

When implementation method 1 is adopted, the second forwarding device stores the F-BM, the first anycast label, and the same information as the first forwarding device through the same entry. The next hop that matches the BFR prefix of the device. For example, the first correspondence relationship includes a first field, a second field, and a third field. The first field includes F-BM, the second field includes a first anycast label, and the third field includes a BFR prefix matching the first forwarding device. the next hop. The first field is, for example, the F-BM field, the second field is, for example, the next hop field, and the third field is, for example, the BFR-NBR field.

Based on implementation method 1, it supports adding fields in the BIFT format defined by BIER related standards, carrying anycast tags through the new fields, and carrying F-BM and next hop through the F-BM field and BFR-NBR field defined by BIFT. In this way, when forwarding on the data plane, the parameters required for forwarding can be obtained by looking up a table entry.

Implementation method 2: The first correspondence relationship includes multiple associated entries.

When using the second implementation method, the second forwarding device can save the F-BM and the next hop that matches the BFR prefix of the first forwarding device through one entry, and save the first hop through another entry associated with the entry. broadcast tag. For example, the first correspondence relationship includes a first entry and a second entry, the first entry includes an F-BM field and a BFR-NBR field, and the second entry includes a first field and a second field. The F-BM field in the first entry includes an F-BM that matches the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device. The BFR-NBR field in the first entry includes an F-BM that matches the BFR-ID of the first forwarding device. The next hop matched by BFR prefix. The first field in the second entry includes the next hop that matches the BFR prefix of the first forwarding device. The second field in the second entry includes the first anycast label.

Based on the second implementation method, the BIFT format defined by the BIER-related standards is supported to implement the BIER forwarding table. For example, the BIER forwarding table includes the above-mentioned first table item. When forwarding on the data plane, the first table item is first searched. If the bit string matches the F-BM in the first table item, the second table item is searched according to the F-BM in the first table item to obtain the next hop. This method is more compatible with the BIER-related standards.

The next hop that matches the BFR prefix of the first forwarding device in the first correspondence relationship includes multiple situations. The following is an example of case A and case B.

Case A. The next hop in the first correspondence relationship that matches the BFR prefix of the first forwarding device is the BFR prefix of the first forwarding device. Since the BFR prefix of the first forwarding device is the IP address of the first forwarding device, it can play a role in identifying the first forwarding device. By saving the BFR prefix of the first forwarding device in the next hop in the corresponding relationship, the second forwarding device can be identified. When the forwarding device forwards the data message, when it finds that the bit string matches the F-BM in the corresponding relationship, it can determine to forward the message to the first forwarding device. For example, in case A, the process of obtaining the first corresponding relationship includes the following Step (a-1) to step (a-3).

Step (a-1) The second forwarding device determines that the first forwarding device and the third forwarding device belong to the first site based on the first anycast label and the second anycast label. How to determine that the first forwarding device and the third forwarding device belong to the first site based on the anycast label includes multiple implementations. The following is an example of implementations I to implementations II.

Implementation Mode I: The second forwarding device compares the first anycast label with the second anycast label, and the second forwarding device determines the first forwarding device and the third forwarding device based on the same first anycast label and the second anycast label. The device belongs to the first site.

Implementation Mode II: The second forwarding device reads specific fields in the first anycast tag and the second anycast tag respectively. The second forwarding device includes the identity of the first site based on the first anycast tag, and the second anycast tag Including the identification of the first site, it is determined that the first forwarding device and the third forwarding device belong to the first site.

For example, the first anycast label is the End.BIER SID of the first forwarding device, and the function field or parameter field in the first anycast label includes the identity of the first site. The second anycast label is the End.BIER SID of the third forwarding device, and the function field or parameter field in the second anycast label includes the identity of the first site. The second forwarding device reads the function field or parameter field in the first anycast tag to obtain the identity of the first site. The second forwarding device reads the function field or parameter field in the second anycast tag to obtain the identity of the first site. Since the second forwarding device has obtained the identity of the first site from both the first anycast label and the second anycast label, it determines that the first forwarding device and the third forwarding device belong to the first site.

Step (a-2) The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device. For example, the second forwarding device obtains the bit string A corresponding to the BFR-ID of the first forwarding device based on the BFR-ID of the first forwarding device; the second forwarding device obtains the bit string A corresponding to the BFR-ID of the third forwarding device based on the BFR-ID of the third forwarding device. The bit string B corresponding to the BFR-ID of the forwarding device; the second forwarding device combines the bit string A and the bit string B to obtain the F-BM. For example, the second forwarding device performs an OR operation on bit string A and bit string B, so that bit string A and bit string B are combined into F-BM.

As a specific example, the BFR-ID of the first forwarding device is 2, and the BFR-ID of the third forwarding device is 3. Based on the BFR-ID (2) of the first forwarding device, the second forwarding device obtains that the bit string A corresponding to the BFR-ID of the first forwarding device is 0010. Based on the BFR-ID (3) of the third forwarding device, the second forwarding device obtains that the bit string B corresponding to the BFR-ID of the third forwarding device is 0100. The second forwarding device performs an OR operation on the bit string A (0010) and the bit string B (0100) to obtain 0110. 0110 is the F-BM, and 0110 means that the device with BFR-ID 2 and the device with BFR-ID 3 can be reached.

Step (a-3) The second forwarding device obtains the first correspondence based on the F-BM, the first anycast label, and the BFR prefix of the first forwarding device. The first correspondence includes the F-BM, the first anycast label, and BFR prefix of the first forwarding device.

In case B, the next hop that matches the BFR prefix of the first forwarding device is the combination of the identifier of the first forwarding device determined based on the BFR prefix of the first forwarding device and the outbound interface of the second forwarding device. The identifier of the first forwarding device is, for example, the BFR prefix of the first forwarding device, or another IP address other than the BFR prefix of the first forwarding device. For example, in case B, the process of obtaining the first correspondence includes the following steps (b-1) to step (b-4).

Step (b-1) The second forwarding device determines that the first forwarding device and the third forwarding device belong to the first site based on the first anycast label and the second anycast label;

Step (b-2) The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

Step (b-3) The second forwarding device determines the first outbound interface on the second forwarding device that reaches the first forwarding device based on the BFR prefix of the first forwarding device.

In a possible implementation, the second forwarding device communicates with the first forwarding device, and the second forwarding device uses the interface that receives the first parameter set as the first outgoing interface. In another possible implementation, based on the BFR prefix of the first forwarding device, the second forwarding device searches the routing table for the interface through which the device communicates with the BFR prefix of the first forwarding device as the first outgoing interface.

Step (b-4) The second forwarding device obtains the first corresponding relationship based on the F-BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outgoing interface. The first corresponding relationship includes the F-BM, the first anycast label, and the first outgoing interface. An anycast label, the BFR prefix of the first forwarding device, and the first outgoing interface.

Step S208: The second forwarding device obtains the second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device.

The second corresponding relationship includes the F-BM that matches the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, the second anycast label, and the next hop that matches the BFR prefix of the third forwarding device. The second correspondence relationship can be implemented through one entry, or through multiple associated entries. For the implementation method, please refer to the above description of the first correspondence relationship.

The next hop that matches the BFR prefix of the third forwarding device in the second correspondence relationship includes multiple situations. The following uses case A and case B as examples.

In case A, the next hop that matches the BFR prefix of the third forwarding device in the second correspondence is the BFR prefix of the third forwarding device. In case A, the process of obtaining the second correspondence includes the following steps (a-1) to (a-3).

Step (a-1) The second forwarding device determines that the first forwarding device and the third forwarding device both belong to the first site based on the first anycast label and the second anycast label;

Step (a-2) The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

Step (a-3) The second forwarding device obtains the second pair based on the F-BM, the second anycast label and the BFR prefix of the third forwarding device. The second correspondence relationship includes the F-BM, the second anycast label, and the BFR prefix of the third forwarding device.

In case B, the next hop that matches the BFR prefix of the third forwarding device is the combination of the identifier of the third forwarding device determined based on the BFR prefix of the third forwarding device and the outbound interface of the second forwarding device. For example, in case B, the process of obtaining the second correspondence relationship includes the following steps (b-1) to step (b-4).

Step (b-1) The second forwarding device determines that the first forwarding device and the third forwarding device both belong to the first site based on the first anycast label and the second anycast label.

Step (b-2) The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device.

Step (b-3) The second forwarding device determines the second outbound interface on the second forwarding device that reaches the third forwarding device based on the BFR prefix of the third forwarding device.

In a possible implementation, the second forwarding device communicates with the third forwarding device, and the second forwarding device uses the interface that receives the second parameter set as the second outgoing interface. In another possible implementation, based on the BFR prefix of the third forwarding device, the second forwarding device searches the routing table for the interface through which the device communicates with the BFR prefix of the third forwarding device as the second outgoing interface.

Step (b-4) The second forwarding device obtains a second correspondence based on the F-BM, the second anycast label, the BFR prefix of the third forwarding device, and the second outbound interface. The second correspondence includes the F-BM, the The second anycast label, the BFR prefix of the third forwarding device and the second outgoing interface.

From the parameters included in the first correspondence and the second correspondence, it can be seen that since the F-BM in the first correspondence reflects the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, and the second correspondence The F-BM in also reflects the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device. Therefore, if the bit string in the data message contains either the first forwarding device or the third forwarding device, When the BFR-ID is specified, you can choose to forward the packet to the next hop in either the first correspondence or the second correspondence, even if the next hop included in one of the first correspondence or the second correspondence appears. In the event of a fault, packets can also be forwarded to another included next hop without convergence, thereby avoiding traffic interruption and achieving fast switching and traffic protection in fault scenarios.

In the method provided by this embodiment, the second forwarding device receives two parameter sets from the first forwarding device and the third forwarding device in the first site, and according to the anycast labels contained in the two parameter sets both identify the first site, The BFR-IDs of the first forwarding device and the third forwarding device are reflected in the same corresponding relationship, which is equivalent to binding multiple devices in the same site together through anycast labels. Then when a data packet is received , if the link to one of the devices in the first site fails, the F-BM in the corresponding relationship can be matched according to the bit string in the data message, and the data message can be forwarded directly to the next hop in the corresponding relationship. There is no need to recalculate the next hop through route convergence, thus increasing the speed of convergence switching and achieving traffic protection.

The above embodiment of Figure 4 focuses on describing the control plane configuration process and the process of obtaining the corresponding relationship. The corresponding relationship obtained by the embodiment of Figure 4 can be used to forward the data message when receiving the data message. The following uses the diagram of the embodiment of Figure 5 The corresponding relationship in Embodiment 4 is used to illustrate the message forwarding process.

FIG. 5 is a flow chart of a method for processing multicast data packets provided by an embodiment of the present application. The embodiment shown in FIG. 5 includes the following steps S211 to S213.

Step S211: The second forwarding device obtains the first BIER message.

The first BIER message includes a first bit string, a label of the second forwarding device, and a multicast data message. For example, the first BIER message includes a first message header, and the first message header includes a first bit string and a label of the second forwarding device. The payload of the first BIER message includes a multicast data message.

The first bit string corresponds to one or more of the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device. The value of the first bit string includes multiple cases, and the following is an example combining three cases.

Case 1: The first bit string corresponds to the BFR-ID of the first forwarding device, but does not correspond to the BFR-ID of the third forwarding device. For example, the bit corresponding to the BFR-ID of the first forwarding device in the first bit string is set, but the bit corresponding to the BFR-ID of the third forwarding device is not set.

Case 2: The first bit string corresponds to the BFR-ID of the third forwarding device and does not correspond to the BFR-ID of the first forwarding device. For example, in the first bit string, the bit corresponding to the BFR-ID of the third forwarding device is set, but the bit corresponding to the BFR-ID of the first forwarding device is not set.

Case 3: The first bit string corresponds to both the BFR-ID of the third forwarding device and the BFR-ID of the first forwarding device. For example, in the first bit string, the bit bit corresponding to the BFR-ID of the third forwarding device is set, and the bit bit corresponding to the BFR-ID of the first forwarding device is both set.

The "bit string corresponding to the BFR-ID" described above means, for example, that the bit position corresponding to the BFR-ID in the bit string is set. For example, the BFR-ID of the first forwarding device is k, and the k-th bit from right to left in the first bit string is set, that is, the first bit string corresponds to the BFR-ID of the first forwarding device.

The first bit string corresponding to the BFR-ID of the first forwarding device means that the first forwarding device is the destination BFER of the multicast data message. The first bit string corresponding to the BFR-ID of the third forwarding device means that the third forwarding device is the destination BFER of the multicast data message. The first bit string corresponds to the BFR-ID of the third forwarding device and the BFR-ID of the first forwarding device, which means that both the first forwarding device and the third forwarding device are destination BFERs of the multicast data packet.

The label of the second forwarding device is used to identify the second forwarding device. For example, the label of the second forwarding device is the BIER MPLS label of the second forwarding device, and the BIER MPLS label of the second forwarding device is used to determine the BIFT of the second forwarding device. For example, the message header of the first BIER message includes a BIFT-ID field, and the BIFT-ID field includes a label of the second forwarding device.

For another example, the label of the second forwarding device is the End.BIER SID of the second forwarding device. The End.BIER SID of the second forwarding device is used to instruct the second forwarding device to forward the multicast data packet based on BIER. For example, the message header of the first BIER message includes a destination address field, and the destination address field includes the End.BIER SID of the second forwarding device.

How the second forwarding device obtains the first BIER message includes multiple implementation methods. The following is an example of two scenarios.

Scenario A, the second forwarding device is a BFIR scenario.

For example, the second forwarding device receives the multicast data packet from the multicast source. The second forwarding device encapsulates the first message header into the multicast data message and obtains the first BIER message. For example, the second forwarding device searches the multicast forwarding table according to the multicast source group information in the multicast data packet. The second forwarding device determines that the multicast data packet is to be forwarded through the BIER type path based on the table lookup result, and then encapsulates the first packet header into the multicast data packet.

Scenario B: The second forwarding device is transit BFR.

For example, the second forwarding device receives the third BIER message from the previous hop BFR, and the third BIER message includes the third bit string and the multicast data message. The second forwarding device obtains the first BIER message based on the third BIER message. The first bit string is obtained based on the third bit string and the F-BM in BIFT on the second forwarding device. The first BIER message and the third BIER message have the same payload.

Step S212: The second forwarding device obtains the second BIER message based on the first BIER message and the first corresponding relationship.

The second BIER message includes a second bit string, a first anycast label and a multicast data message. For example, the message header of the second BIER message includes the second bit string and the first anycast label, and the payload of the second BIER message includes the multicast data message.

The second bit string is obtained based on the F-BM in the first correspondence relationship between the first bit string and the first bit string. For example, the second bit string is obtained by performing an AND operation on the first bit string and F-BM. For example, the first bit string is 1100, F-BM is 0110, the second bit string is 110 0&0110=0100, & represents the AND operation. In some embodiments, the second forwarding device updates the bit string in the first BIER message from the first bit string to the second bit string, so that the second BIER message includes the second bit string.

As described in the above embodiment, the first anycast label is used to identify the first site. Since the second BIER message includes the first anycast label, the second BIER message can be forwarded to any device in the first site.

The carrying position of the first anycast tag includes various situations. For example, the first anycast label is a BIER MPLS label, the header of the second BIER packet includes a BIFT-ID field, and the BIFT-ID field includes the first anycast label. For another example, the first anycast label is End.BIER SID, the packet header of the second BIER message includes the destination address field, and the destination address field includes the first anycast label.

The first anycast tag is obtained, for example, by searching for the first correspondence. For example, the second forwarding device obtains the first bit string from the first BIER message, searches for the first correspondence based on the first bit string, and obtains the first anycast label corresponding to the first bit string.

In a possible implementation, the first corresponding relationship is an entry in the BIFT of the second forwarding device, and the second forwarding device obtains the first anycast label in the process of searching for the BIFT. For example, the second forwarding device uses the first bit string to match each F-BM in the BIFT of the second forwarding device. The second forwarding device determines to forward the message to the next hop in the first correspondence based on the match between the first bit string and the F-BM in the first correspondence in BIFT. Therefore, based on the F-BM in the first correspondence, the second forwarding device BM and the first anycast label, perform the steps of obtaining and sending the second BIER message. How to determine whether the first bit string matches the F-BM includes multiple methods. For example, the second forwarding device uses the first bit string to perform an AND operation with the F-BM to obtain the second bit string. Based on the fact that the second bit string is not all zeros, the second forwarding device determines that the first bit string matches the F-BM in the first correspondence relationship in the BIFT.

In some embodiments, the second forwarding device updates fields in the header of the first BIER message so that the second BIER message includes the first anycast label. The following is an example of two scenarios.

Scenario 1. Configure BIER in the MPLS network.

Scenario 1 is, for example, a BIER-MPLS scenario. In the first scenario, the first anycast label is, for example, the BIER MPLS label of the first forwarding device, and the BIFT-ID field in the header of the first BIER message includes the BIER MPLS label of the second forwarding device. The second forwarding device uses the first anycast label to update the BIFT-ID field in the header of the first BIER packet, so that the BIFT-ID field in the header of the second BIER packet includes the BIER MPLS label of the first forwarding device. , which is the first anycast tag.

Scenario 2: Configure BIER in the IPv6 network.

Scenario 2 includes but is not limited to any one of BIERv6, BIERin6 or G-BIER scenarios. For specific details, please refer to the description after the title "BIER Encapsulation Format" below.

In scenario 2, the first anycast label is, for example, the End.BIER SID of the first forwarding device, and the destination address field in the header of the first BIER message includes the End.BIER SID of the second forwarding device. The second forwarding device uses the first anycast label to update the destination address field in the header of the first BIER message, so that the destination address field in the header of the second BIER message includes the End.BIER SID of the first forwarding device, That is the first anycast tag.

Step S213: The second forwarding device sends the second BIER message.

The destination of the second BIER message sent by the second forwarding device includes many situations. Two situations are given as examples below.

Scenario 1: The second forwarding device sends the second BIER message to the next hop in the first corresponding relationship.

For example, the next hop in the first correspondence is the BFR prefix of the first forwarding device, and the second forwarding device uses the BFR prefix of the first forwarding device as the IP address of the next hop, and sends the BFR prefix of the first forwarding device. 2. BIER message. For another example, the next hop in the first correspondence relationship includes the first outbound interface on the second forwarding device that reaches the first forwarding device, and the second forwarding device sends the second BIER message through the first outbound interface. For another example, the next hop in the first correspondence relationship includes the BFR prefix of the first forwarding device and the first outbound interface of the second forwarding device to the first forwarding device. The second forwarding device sends the packet to the first forwarding device through the first outbound interface. The BFR prefix of the forwarding device sends the second BIER message.

Case 2: The second forwarding device sends the second BIER message to the next hop in the second corresponding relationship. For example, in the second correspondence The next hop is the BFR prefix of the third forwarding device. The second forwarding device uses the BFR prefix of the third forwarding device as the IP address of the next hop and sends the second BIER message to the BFR prefix of the third forwarding device. For another example, the next hop in the second correspondence relationship includes a second outbound interface on the second forwarding device that reaches the third forwarding device, and the second forwarding device sends the second BIER message through the second outbound interface. For another example, the next hop in the second corresponding relationship includes the BFR prefix of the third forwarding device and the second outbound interface on the second forwarding device to reach the third forwarding device. The second forwarding device passes the second outbound interface to the third forwarding device. The BFR prefix of the forwarding device sends the second BIER message.

The second forwarding device chooses to use the first correspondence relationship or the second correspondence relationship to send the message, including multiple implementation methods. The following is an example of two scenarios.

Scenario 1. Failure scenario

The applicable fault scenarios of this embodiment include but are not limited to link failure or node failure. A link failure is, for example, a link failure between the second forwarding device and the next hop in the corresponding relationship. A node failure is, for example, a device failure at the next hop in the corresponding relationship obtained by the second forwarding device.

When the second forwarding device detects that a node failure or a link failure occurs in the next hop in either of the first correspondence relationship and the second correspondence relationship, because the F-BM values in the two correspondence relationships are the same, or If both correspondences match the bit string in the data message, the second forwarding device can send the message to the next hop in the other correspondence, thus avoiding traffic interruption due to a fault.

For example, if the next hop in the first correspondence that matches the BFR prefix of the first forwarding device is in a fault state, the second forwarding device sends a message to the next hop in the second correspondence that matches the BFR prefix of the third forwarding device. The second BIER message. The failure state of the next hop matching the BFR prefix of the first forwarding device includes but is not limited to a link failure between the second forwarding device and the first forwarding device or a failure of the first forwarding device.

For another example, if the next hop in the second correspondence that matches the BFR prefix of the third forwarding device is in a fault state, the second forwarding device sends a request to the next hop in the first correspondence that matches the BFR prefix of the first forwarding device. Send the second BIER message. The failure state of the next hop matching the BFR prefix of the third forwarding device includes but is not limited to a link failure between the second forwarding device and the third forwarding device or a failure of the third forwarding device.

Scenario 2. Scenario where no failure occurs

In a scenario where no failure occurs, the method by which the second forwarding device selects the next hop includes, but is not limited to, the following methods one to three.

Method 1. Choose at will

For example, if the next hop that matches the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the third forwarding device are not in a faulty state, the second forwarding device sends a second BIER message to any one of the next hop that matches the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the third forwarding device. For example, the second forwarding device randomly selects one of the next hops that match the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the third forwarding device as the next hop of the second BIER message, and sends the second BIER message to the randomly selected next hop.

Optionally, in a scenario where the second forwarding device communicates with the first forwarding device and the third forwarding device, the second forwarding device forwards the BIER message using method one. Through the above method 1, the load sharing scenario is supported, which helps the multicast data flow to be evenly shared on the link between the second forwarding device and the first forwarding device and the link between the second forwarding device and the third forwarding device. Avoid overloading a single link.

Method 2: Select based on link cost

Link cost is used to represent the distance of the network path, such as the number of hops that the network path passes through. The link cost can be represented by cost or metric. If the next hop that matches the BFR prefix of the first forwarding device and the next hop that matches the BFR prefix of the third forwarding device are not in a fault state, the second forwarding device can transfer the next hop that matches the BFR prefix of the first forwarding device. Next hop and to third forwarding device Among the next hops matched by the BFR prefix, the one with the smallest link cost is used as the better next hop, and the second BIER message is sent to the next hop with the smallest link cost.

For example, if the link cost between the second forwarding device and the first forwarding device is less than the link cost between the second forwarding device and the third forwarding device, the second forwarding device sends a second BIER message to the first forwarding device. . For another example, if the link cost between the second forwarding device and the third forwarding device is less than the link cost between the second forwarding device and the first forwarding device, the second forwarding device sends a second BIER message to the third forwarding device. arts.

Method 3: Select based on link quality

Link quality includes but is not limited to link delay, jitter, link bandwidth, or packet loss rate. The smaller the link delay, the higher the link quality. The larger the link bandwidth, the higher the link quality. The smaller the link packet loss rate, the higher the link quality.

In some embodiments, if the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device are not in a faulty state, the second forwarding device sends a second BIER message to the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device, whichever has the highest link network quality.

For example, if the link quality between the second forwarding device and the first forwarding device is higher than the link quality between the second forwarding device and the third forwarding device, the second forwarding device sends a second BIER message to the first forwarding device. For another example, if the link quality between the second forwarding device and the third forwarding device is higher than the link quality between the second forwarding device and the first forwarding device, the second forwarding device sends a second BIER message to the third forwarding device.

The above embodiments in Figure 4 and Figure 5 focus on describing the control plane configuration and data plane forwarding process related to the anycast label. Some embodiments of the present application also provide the control plane configuration and data plane forwarding process related to the bypass label. Hereinafter, The embodiment in Figure 6 and the embodiment in Figure 7 are illustrated.

Figure 6 is a flow chart of a method for obtaining a correspondence relationship provided by an embodiment of the present application. The method shown in Figure 6 includes the following steps S221 to S229.

Step S221: The third forwarding device in the first site obtains the third parameter set.

The third parameter set includes the first bypass label, the BFR-ID of the third forwarding device, and the BFR prefix of the third forwarding device. The first bypass label is used to identify the third forwarding device. In some embodiments, the first bypass tag is the End.BIER SID of the third forwarding device. In other embodiments, the first bypass label is an MPLS label of the third forwarding device. The value of the first bypass tag is different from the above-mentioned second anycast tag and the above-mentioned first anycast tag.

Step S222: The first forwarding device in the first site obtains the fourth parameter set.

The fourth parameter set includes a second bypass label, a BFR-ID of the first forwarding device, and a BFR prefix of the first forwarding device. The second bypass label is used to identify the first forwarding device. In some embodiments, the second bypass label is the End.BIER SID of the first forwarding device. In other embodiments, the second bypass label is an MPLS label of the first forwarding device.

Step S223: The third forwarding device sends the third parameter set to the first forwarding device in the first site.

Step S224: The first forwarding device sends the fourth parameter set to the third forwarding device in the first site.

Step S225: The first forwarding device receives the third parameter set from the third forwarding device in the first site.

Step S226: The third forwarding device receives the fourth parameter set from the first forwarding device.

Step S227: The first forwarding device obtains the third correspondence based on the third parameter set.

The third corresponding relationship includes the first bypass label, the F-BM matching the BFR-ID of the third forwarding device, and the next hop matching the BFR prefix of the third forwarding device.

Step S228: The third forwarding device obtains the fourth correspondence based on the fourth parameter set.

The fourth corresponding relationship includes the second bypass label, the F-BM matching the BFR-ID of the first forwarding device, and the next hop matching the BFR prefix of the first forwarding device.

In the method provided in this embodiment, the forwarding device establishes a corresponding relationship between the F-BM that matches the BFR-ID of the peer device in the same site, the bypass label of the peer device in the same site, and the next hop, which is equivalent to opening up the relationship. The routing within the site enables the forwarding device to match the F-BM based on the bit string when receiving a data packet containing a bit string matching the BFR-ID of the peer device, and use the peer device in the same site as the next hop. , use the bypass label of the peer device in the same site as the label of the next hop to forward the packet, and the packet forwarding will not be terminated because the label of the next hop is the label of the local device.

In an exemplary scenario, when a link failure occurs and the data packet reaches a forwarding device in a site, the forwarding device finds out that the destination BFER of the data packet is not the device based on the bit string carried in the data packet. The data message can be forwarded to another forwarding device in the same site using the corresponding relationship obtained in the embodiment shown in Figure 6.

For example, please refer to Figure 7. Figure 7 is a flow chart of a data packet processing method provided by an embodiment of the present application. The method shown in Figure 7 is an example of forwarding a packet from a first forwarding device to a third forwarding device. Figure 7 The illustrated embodiment includes the following steps S231 to S233.

Step S231: The first forwarding device in the first site receives the first BIER message.

The first BIER message includes the first bit string corresponding to the BFR-ID of the third forwarding device, the first anycast label and the multicast data message.

Step S232: The first forwarding device in the first site obtains the second BIER message based on the first BIER message and the third corresponding relationship.

The second BIER message includes a second bit string, a first bypass label and a multicast data message.

The second bit string is a bit string obtained based on the F-BM in the first bit string and the third correspondence relationship. For example, the first forwarding device performs an AND operation on the first bit string and the F-BM, and the result obtained by the AND operation is the second bit string.

For example, the first forwarding device searches for the third correspondence based on the first bit string, and performs an AND operation using the F-BM in the first bit string and the third correspondence. The first forwarding device determines to forward the packet to the next hop that matches the BFR prefix of the third forwarding device based on the F-BM matching the first bit string and the BFR-ID of the third forwarding device and the operation result is not all 0. , so based on the first BIER message and the first bypass label, the second BIER message is obtained.

Step S233: The first forwarding device in the first site sends the second BIER message to the third forwarding device in the first site.

In the method provided by this embodiment, when the forwarding device receives a data message containing the corresponding bit string of another device in the same site, it encapsulates the bypass label identifying the other device in the same site into the data message, thereby When copying data packets, packet forwarding will not be terminated because the label in the data packet is a label that identifies itself, allowing different devices in the site to transfer data packets to each other to avoid traffic interruption.

For example, please refer to Figure 8. Figure 8 is a flow chart of a data packet processing method provided by an embodiment of the present application. The method shown in Figure 8 is an example of forwarding a packet from a third forwarding device to a first forwarding device. Figure 8 The illustrated embodiment includes the following steps S241 to S243.

Step S241: The third forwarding device in the first site receives the first BIER message.

The first BIER message includes the first bit string corresponding to the BFR-ID of the first forwarding device, the first anycast label and the multicast data message.

Step S242: The third forwarding device obtains the second BIER message based on the first BIER message and the fourth corresponding relationship.

The second BIER message includes a second bit string, a second bypass label and a multicast data message.

Step S243: The third forwarding device sends the second BIER message to the first forwarding device in the first site.

Any of the above-mentioned embodiments shown in FIG. 4 to the embodiment in FIG. 8 can be implemented independently or in combination. The following is an example of the process of the combined implementation of the embodiment shown in FIG. 4 to the embodiment in FIG. 8 in the BIER-MPLS scenario. In the following embodiments, anycast BIER-MPLS label is a specific example of anycast label in the embodiment shown in Figure 4 to Figure 8. In the following embodiments, bypass BIER-MPLS label is a specific example of anycast label in the embodiment shown in Figure 4 to Figure 8. Specific examples of bypass tags in the embodiment. In the following embodiment, BFR-A of site A is a specific example of the second forwarding device in the second site in the above embodiment. In the following embodiment, BFR-B1 and BFR-B2 of site B are a specific example of the second forwarding device in the second site in the above embodiment. As a specific example of the first forwarding device and the third forwarding device in the first site, the following embodiment includes the following steps 0 to 5.

Step 0: Plan your site.

Deploy multicast source sites, intermediate sites, and multicast receiver sites respectively. Enable the BIER capability of each device and configure the corresponding BIER subdomain and BFR-ID.

Step 1: Deploy IGP or BGP

For example, configure IGP, BGP or other routing protocols on each BFR to flood the BFR prefix. Packets that flood BFR prefix carry BIER-related parameter sets. The parameter sets they carry include: BFR-ID, SI, BSL, and BIER-MPLS label.

Step 2: Flooding BIER-MPLS label

Each BFR in the site is configured with a different BFR-ID.

In this embodiment, the same anycast BIER-MPLS label is used on the devices within the site, and the original BIER-MPLS label is called the bypass BIER-MPLS label. The anycast BIER-MPLS label and the BFR prefix are flooded through the same message. The anycast label is used to generate the inter-site BIER forwarding table, and the bypass label is used to generate the intra-site BIER forwarding table.

A global label block is allocated in the label space to assign anycast labels to each site. The anycast BIER-MPLS label and bypass BIER-MPLS label are carried by the sub-sub-TLV in the BIER information sub-TLV of route flooding.

Figure 9 shows the BIER information sub-TLV. The BIER-MPLS label is filled in the sub-sub-TLV field in the BIER information sub-TLV.

Figure 10 shows the sub-sub-TLV encapsulated by BIER-MPLS, which carries MAX-SI, BSL and BIER-MPLS label.

Among the anycast label and bypass label provided in this embodiment, the bypass label is still encapsulated in the original sub-sub-TLV. The anycast label is encapsulated as shown in the new sub-sub-TLV in Figure 11. The new anycast label sub-sub-TLV is encapsulated behind the original bypass label sub-sub-TLV.

Step 3: Create BIER forwarding table

After the device receives the BIER information sub-TLV of other BFRs, it will parse the bypass label and anycast label of the sub-sub-TLV. Locally maintain the corresponding relationship of [BFR-ID, anycast label, bypass label] in the BIER subdomain.

Step 3-1: Establishment of inter-site forwarding table

As shown in Figure 12, when BFR-A of site A receives the BIER information sub-TLV of BFR-B1 of site B and the BIER information sub-TLV of BFR-B2, BFR-A parses the BIER information sub-TLV of BFR-B1 and The BIER information sub-TLV of BFR-B2 obtains two anycast labels. BFR-A determines that the two anycast labels (label_B) are inconsistent with BFR-A's local anycast label (label_A), but the two anycast labels are consistent with each other, then BFR-A merges the BFR-IDs of BFR-B1 and BFR-B2 into in an F-BM entry.

If the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are equal-cost links, BFR-A will connect the outbound interfaces to BFR-B1 and BFR-B2 with the next hop. Reflected in this F-BM entry. If the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are non-equivalent links, the outbound interface and next hop of the optimal link are reflected in the F-BM entry. . Among them, the outbound interface from BFR-A to BFR-B1 and the outbound interface to BFR-B2 are reflected in BIFT only as an optional method. In other embodiments, BFR-A does not connect the outbound interface to BFR-B1. The interface and the outgoing interface to BFR-B2 are reflected in BIFT. Example of how BFR-A determines the outbound interface If so, BFR-A obtains the outbound interface to BFR-B1 and the outbound interface to BFR-B2 by learning the unicast route, or obtains the outbound interface to BFR-B1 and the outbound interface to BFR-B from the unicast forwarding table. The outbound interface of B2.

For example, when BFR-B1 and BFR-B2 at the edge are configured with BFR-ID, and other BFRs in the BIER subdomain except BFR-B1 and BFR-B2 are not configured with BFR-ID, the F-BM generated by each device will There are only two digits, 01 and 10 respectively.

Without providing anycast label, the BIFT originally generated by BFR-A is shown in Table 1 below.

Table 1

By introducing anycast label, the F-BM of the original BIFT table is merged, and the BIFT generated is as follows.

When the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are equal-cost links, the BIFT of BFR-A is as shown in Table 2-1 or Table 2-2 below.

table 2-1

Table 2-2

When the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are not equal-cost links, the link from BFR-A to BRF-B1 is more expensive than the link from BFR-A to BFR-B2. When better, the BIFT generated by BFR-A is shown in Table 3 below.

table 3

Therefore, anycast label is used to build the inter-site BIER forwarding table.

Step 3-2: Establish the forwarding table within the site

Inside the site, as shown in Figure 13, when BFR-B1 receives the BIER information sub-TLV of BFR-B2, BFR-B1 parses out anycast label (label_B) and bypass label (label_B2), and finds that the anycast label is the same as the local anycast label. If the labels are consistent, BFR-B1 can use the original bypass label to generate BIFT entries to the peer device for packet transfer within the site. When the packet is copied to the peer device, that is, BFR-B2, it carries the bypass label of the peer. The bypass label of BFR-B1 is label_B1, and the bypass label of BFR-B2 is label_B2.

The BIFT generated by BFR-B1 is shown in Table 4 below.

Table 4

The BIFT generated by BFR-B2 is shown in Table 5 below.

table 5

Step 4: After receiving the data message, find BIFT.

In the BIER-MPLS scenario, after receiving the BIER data packet, the bit string and BIER-MPLS label carried in the packet header will be parsed.

When forwarding packets between different sites, when the upstream device encapsulates the packet, anycast label is used to encapsulate the packet header. When forwarding packets to each other within the site, the bypass label is used to encapsulate the packet header.

The corresponding relationship between anycast label, bypass label and <BIER sub-domain, SI, BSL> is maintained on each device.

The device performs an AND operation with the F-BM in the BIFT table based on the bit string to obtain the reachable BFER set in the BIER subdomain and the corresponding BFR neighbors, outgoing interfaces, and next hops.

Step 4-1: This device forms load sharing with two devices at the downstream site at the same time.

As shown in Figure 14, the devices at site A are directly connected to the two devices at site B.

In the BIFT of BFR-A1 and BFR-A2 at site A, there will be outbound interfaces and next hops to the two devices BFR-B1 and BFR-B2 at site B. BFR-A1 or BFR-A2 can use the outbound interface to BFR-B1 to forward packets, or it can use the outbound interface to BFR-B2 to forward packets.

For example, the BIFT generated by BFR-A1 is shown in Table 6 below.

Table 6

BFR-A1 receives a data message, and the bit string in the data message is 01. BFR-A1 uses the bit string 01 to perform an AND operation with F-BM11 in Table 6, BitString&F-BM＝01&11＝01, then BFR-A1 can choose any one of the outbound interfaces directly connected to BFR-B1 and directly connected to BFR-B2 to forward the data message, and replace the BIER-MPLS label carried in the message with label_B. When one of the outbound interfaces directly connected to BFR-B1 and directly connected to BFR-B2 fails to work properly, BFR-A1 can also use another outbound interface without convergence. Therefore, when one of the links from BFR-A1 to BFR-B1 and from BFR-A1 to BFR-B2 fails, BFR-A1 can directly forward traffic through another link to achieve fast switching and traffic protection in fault scenarios.

Step 4-2: When this device only has a link with one device at the downstream site

As shown in Figure 15, the device in site A only has a link with one device in site B. At this time, the forwarding table entry on BFR-A1 has one outgoing interface. For example, the BIFT generated by BFR-A1 is shown in Table 7 below. The bit string carried in the data message is 01. BFR-A1 uses the bit string 01 to perform the AND operation with the F-BM in Table 7. The bit string &F-BM=01&11=01,

Table 7

Then BFR-A1 can send data packets from the outbound interface directly connected to BFR-B1, and use label_B to replace the label carried in the data packets.

When the outbound interface of BFR-A1 directly connected to BFR-B1 becomes unavailable due to link or node failure, BFR-A1 needs to converge to the link to BFR-B1. BFR-A1 switches the outbound interface from the interface directly connected to BFR-B1 to the interface directly connected to BFR-A2, and obtains the BIFT shown in Table 8 below.

Table 8

When the data packet reaches BFR-A2, a forwarding table entry has been generated on BFR-A2 to reach BFR-B2. The forwarding table entry is shown in Table 9 below. The meaning of this forwarding table entry is that the next hop is BFR-B2. , the label of the next hop is label_B, and the outbound interface is the interface directly connected to BFR-B2. BFR-A2 can directly use this entry to forward data packets, and will not converge back to BFR-A1, so it will not occur again. Microring problem. At this time, compared to using different labels, it is faster to open up traffic forwarding.

Table 9

Step 5: Search for BIFT after receiving the data packet at the destination site

When a device in the site receives a data packet and determines that the destination BFR of the data packet is not the device, the forwarding table generated based on the bypass label can be used to forward the data packet.

For example, the BIFT generated by BFR-B2 contains the entries shown in Table 10. BFR-B2 receives the data message. The bit string carried in the data message is 01. BFR-B2 uses the bit string 01 to perform the AND operation with F-BM 01 in Table 10. The bit string &F-BM=01&01=01, BFR-B2 forwards data packets through the interface directly connected to BFR-B1, and uses label_B1 to replace the label carried in the data packet.

Table 10

The following is an example of the process of combined implementation of the embodiment shown in Figure 4 to Figure 8 in the BIERv6 scenario. In the following embodiments, the anycast End.BIER SID is a specific example of anycast tag in the embodiment shown in Figure 4 to the embodiment shown in Figure 8. In the following embodiments, the bypass End.BIER SID is the implementation shown in Figure 4 Let's take a specific example of the bypass tag in the embodiment shown in FIG. 8 . This embodiment includes the following steps 0 to 5.

Step 0: Plan the site

Deploy multicast source sites, intermediate sites and multicast receiver sites respectively. Enable the BIER capability of each device and configure the corresponding BIER subdomain and BFR-ID.

Step 1: Deploy IGP or BGP

Each BFR is configured with IGP, BGP or other routing protocols for flooding the BFR prefix. The message flooding the BFR prefix carries the BIER related parameter set. The carried parameter set includes: BFR-ID, SI, BSL and End.BIER SID.

Step 2: Flood the End.BIER SID

In BIERv6 scenario, each BFR in the site is configured with a different BFR-ID.

In this embodiment, the same anycast End.BIER SID and different bypass End.BIER SID are used on the devices inside the site. Use anycast End.BIER SID to generate inter-site BIFT tables, and use bypass End.BIER SID to generate intra-site BIFT tables.

Configure different anycast End.BIER SIDs between different sites to distinguish the sites.

Deploy IGP BIERv6, flood BIERv6 information through IGP, and establish a BIERv6 forwarding table within the site.

As shown in Figure 16, the BIER parameter set is encapsulated in the sub-TLV of the IGP message and is used to calculate the BIER routing table and the BIER forwarding table. Among them, the End.BIER SID is encapsulated in the sub-sub-TLV. As shown in Figure 17, the End.BIER SID is encapsulated in the sub-sub-TLV.

After this embodiment proposes anycast End.BIER and bypass End.BIER, bypass End.BIER is encapsulated in the original End.BIER sub-sub-TLV in Figure 17, and anycast End.BIER is encapsulated as shown in Figure 18. The format is consistent with the existing End.BIER sub-sub-TLV, and is placed after the existing End.BIER sub-sub-TLV during encapsulation.

Step 3: Create BIERv6 forwarding table

Step 3-1: Create an inter-site forwarding table

As shown in Figure 19, between different sites, when two downstream devices BFR-B1 and BFR-B2 notify a BFR-A of sub-sub-TLV, BFR-A resolves the two sub-sub-TLVs. Obtain anycast End.BIER, BFR-A finds that the obtained anycast End.BIER is inconsistent with the local anycast End.BIER, but the anycast End.BIER of BFR-B1 is consistent with the anycast End.BIER of BFR-B2, then BFR-A will The BFR-ID of BFR-B1 and the BFR-ID of BFR-B2 are merged in F-BM.

If the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are equal cost links, BFR-A uses the outbound interfaces to BFR-B1 and BFR-B2 as the outbound interfaces of the F-BM.

And if the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are unequal links, then BFR-A uses the link from BFR-A to BFR-B1 and the link from BFR-A to The outbound interface of the better link among the BFR-B2 links is used as the outbound interface of the F-BM.

In the absence of anycast End.BIER, the BIFT originally generated by BFR-A is shown in Table 11 below.

Table 11

By introducing anycast End.BIER, the F-BM of the original BIFT table is merged to generate the BIFT as shown below.

When the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are equal-cost links, the BIFT of BFR-A is as shown in Table 12 below.

Table 12

When the link from BFR-A to BFR-B1 and the link from BFR-A to BFR-B2 are not equal-cost links, the link from BFR-A to BFR-B1 is more expensive than the link from BFR-A to BFR-B2. When better, the BIFT generated by BFR-A is shown in Table 13 below.

Table 13

Step 3-1: Create an intra-site forwarding table

As shown in Figure 20, inside the site, BFR-B1 parses the sub-sub-TLV of BFR-B2, compares anycast End.BIER, and finds that it is consistent with the local anycast End.BIER, so it uses the bypass End.BIER that is inconsistent with the local one. , as the next hop End.BIER to the opposite end, so that after the received data packet contains the BFR-ID bit string to the opposite end device, when the data packet is copied, it will not be because the next hop End.BIER is It terminates packet forwarding by itself and realizes the purpose of transmitting data packets to each other within the site.

For example, the BIFT generated by BFR-B1 is shown in Table 14 below. Table 14 is a specific example of the BIER forwarding table within the site on BFR-B1.

Table 14

For example, the BIFT generated by BFR-B2 is shown in Table 15 below. Table 15 is a specific example of the BIER forwarding table within the site on BFR-B2.

Table 15

Step 4: Search for BIFT after receiving the data message

After receiving the data message in the BIERv6 encapsulation format, the End.BIER SID carried in the message header will be parsed. When the End.BIER SID is the local End.BIER SID, BIERv6 forwarding processing is performed. When the End.BIER SID is not the local End.BIER SID, the ordinary unicast packet forwarding process is performed.

When performing BIERv6 forwarding processing, after comparing the bit string with the F-BM, the BFR neighbor and the End.BIER SID of the next hop are obtained, and the message is copied and forwarded.

Step 4-1: When this device has links with two devices at the downstream site at the same time

When the device BFR-A1 has a link with two devices at the downstream site, and the two links are equivalent, there will be outbound interfaces to both devices in the forwarding table, and the BIER message can be forwarded to any of the two outbound interfaces. When one of the links fails, the traffic can be directly forwarded through the other link, achieving fast switching and traffic protection in the failure scenario.

For example, the BIFT generated by BFR-A1 is shown in Table 16 below. BFR-A1 receives the data message. The bit string carried in the data message is 01. BFR-A1 uses bit string 01 to perform AND operation with F-BM 11 in Table 16. Bit string &F-BM=01&11=01. BFR-A1 can send packets from one of the two outbound interfaces directly connected to BFR-B1 and BFR-B2. Use End.BIER_B to replace the End.BIER SID carried in the packet header.

Table 16

When one of the two outbound interfaces directly connected to BFR-B1 and BFR-B2 fails to work properly, the other outbound interface can be used to send data packets without convergence.

Step 4-2: When this device only has a link with a device at a downstream site

As shown in Figure 22, when BFR-A1 is connected to only one downstream device BFR-B1, when the link from BFR-A1 to BFR-B1 fails, the forwarding table needs to be re-converged so that BFR-B2 can receive the report. arts.

For example, BFR-A1 converges the next hop from BFR-B1 to BFR-A2. The BIFT of BFR-A1 after convergence is shown in Table 17 below.

Table 17

BFR-A2 originally has a forwarding table to BFR-ID 1 with BFR-B2 as the next hop, as shown in Table 18 below. Therefore, BFR-A2 can directly converge to BFR-B2 without converging back to BFR-A1.

Table 18

Compared with hard convergence when using different End.BIER SIDs, using the same End.BIER SID can avoid the generation of micro-rings and open up traffic forwarding faster.

Step 5: After receiving the data message, the destination site searches for BIFT.

When a packet reaches the site but the destination BFR is not the device, the BIFT generated by bypass End.BIER can be used to forward the packet.

For example, the BIFT generated by BFR-B2 contains the entries shown in Table 19. BFR-B2 receives the data message. The header of the data message carries bit string 01. BFR-B2 uses bit string 01 and F-BM 01. Perform the AND operation, bit string &F-BM=01&01=01, then BFR-B2 sends the message from the interface directly connected to BFR-B1, and uses End.BIER_B1 to replace the End.BIER SID carried in the message header.

Table 19

Then the packet can be forwarded to another BFR within the site, namely BFR-B1, through End.BIER_B1. BFR-B1 further forwards the packet to the destination BFR.

The embodiment shown in Figure 4 to Figure 8 will be described below with reference to the BIER-MPLS networking scenario shown in Figure 23.

As shown in Figure 23, the multicast root node is site 1 directly connected to the multicast source. The multicast leaf node is the site 3 to which the multicast receiver is directly connected. Site 2 represents the intermediate node.

Both the root node and leaf nodes enable the BIER capability, serve as BFR nodes, and are assigned BFR-IDs.

In this example, site 1 and site 3 serve as BFIR and BFER respectively.

PE3 has interface 1, interface 2 and interface 3. Interface 1 is the outbound interface from PE3 to PE4, interface 2 is the outbound interface from PE3 to PE5, and interface 3 is the outbound interface from PE3 to PE6. PE6 has interface 4, which is the outbound interface from PE6 to PE5.

For the scenario in Figure 23, the embodiment includes the following steps 1 to 6.

Step 1: Deploy BIER-MPLS:

The root node, intermediate node and leaf node are uniformly configured with BIER sub-domain id of 1, BSL of 64 and SI of 1. The BFR-ID of each device is different; the intermediate node is not configured with BFR-ID, but supports BIER forwarding;

Two devices at the same site are configured with the same anycast BIER-MPLS label and different bypass BIER-MPLS labels; different sites are configured with different anycast BIER-MPLS labels.

Two devices in the same site are deployed with BIER, and the two devices in the site establish BIER forwarding tables. Packets can be forwarded in the site through BIER.

For example, the configuration of each device shown in FIG. 23 is as shown in Table 20.

Table 20

Step 2: Announce BIER parameter set

Each device in the BIER subdomain advertises the BIER parameter set through the deployed IGP or BGP. Each device generates a routing table and forwarding table by advertising the obtained BIER parameter set.

For example, PE 5 sends the BIER information sub-TLV shown in Figure 24. The sub-sub-TLV in Figure 24 carries the bypass label, and the value of the bypass label is 31.

Figure 25 shows the newly added sub-sub-TLV, which is used to carry the anycast label. The value of the anycast label is 30.

Figure 26 shows the BIER information sub-TLV of PE6.

After PE3 receives the BIER information sub-TLV of PE5 and PE6, PE3 will parse the anycast label and bypass label.

The value of PE3's anycast label is 20, and the value of PE3's bypass label is 21. When PE3 parses and obtains PE5's anycast label 30, PE3 compares PE5's anycast label with its own anycast label and finds that the two are inconsistent. It then records label 30 as the label of the next hop to BFR-ID 5 in the current <sub-domain, SI, BSL>, and records the outbound interface as the interface directly connected to PE5. Similarly, the next hop label from PE3 to BFR-ID 6 is also 30.

Step 3: Generate BIFT table

In the BIFT table, PE3 merges the two BFR-IDs of PE5's BFR-ID and PE6's BFR-ID into the same F-BM. For example, refer to Table 21 below. Table 21 shows the BIFT of PE 3. The index of the BIFT of PE 3 is <SD: 1, SI: 1, BSL: 64>. BFR-ID of PE5 is 5, and the BFR-ID of PE6 is 6, then a bit string with a length of 64 is generated, and the 5th bit from the right and the 6th bit from the right of the bit string are set to obtain F-BM 110000. To simplify the illustration, the last 6 bits of F-BM are shown here. The first 58 bits of F-BM are all 0. The first 58 bits of F-BM are omitted and not shown here. The next hop label corresponding to F-BM is 30. The link from PE3 to PE5 and the link from PE3 to PE6 are equal-cost links, so the BFR-NBR is PE5 and PE6, and the outgoing interfaces are the interface from PE3 to PE5 and the interface from PE3 to PE6 respectively.

Table 21

In the same way, PE1 generates BIFT, as shown in Table 22 below. The BIFT index of PE 1 is <SD:1,SI:1,BSL:64>.

Table 22

PE6 receives the BIER information sub-TLV of PE5, parses the sub-sub-TLV in the BIER information sub-TLV, and the parsed label is 30, which is consistent with the local anycast label 30. PE6 parses the bypass label as 31, and records label 31 as the next hop label to BFR-ID 5 in the current <sub-domain, SI, BSL> BIFT table, as shown in Table 23.

Table 23

Similarly, PE5 generates the BIFT table entry shown in Table 24.

Table 24

Step 4: Forward the multicast data packet.

The multicast source sends multicast data packet 1, and the destination recipient of multicast data packet 1 is receiver 2 connected to PE5.

After receiving multicast data packet 1, PE1 adds a header containing a bit string to multicast data packet 1 to obtain multicast data packet 2. The bit string contains the destination BFER that the packet needs to reach, that is, the BFR-ID of PE5. The bit string is 010000. Based on the comparison result between the bit string and the F-BM in BIFT on PE1, PE1 determines that the next hop label is label 20, and the outbound interface is the interface pointing to PE3 or PE4. When the neighbor on PE1 that reaches PE1 has two outgoing interfaces, PE1 selects one of the outgoing interfaces to forward multicast data packet 2.

When PE1 sends multicast data packet 2 through the interface pointing to PE3, PE3 receives multicast data packet 2. PE3 compares the bit string in multicast data packet 2 with BIFT and finds that the next hop label is 30. PE3 forwards multicast data packet 3 from the outgoing interface pointing to PE5. Multicast data packet 3 is based on multicast Obtained from data packet 2, the bit string in multicast data packet 3 is based on the ratio in multicast data packet 2. The special string is obtained by performing and operating F-BM in BIFT of PE3.

After multicast data packet 3 reaches PE5, PE5 compares the bit string in multicast data packet 3 with the F-BM on PE5 and finds that the local machine is the destination BFER. Then PE5 decapsulates the multicast data packet 3 containing The message header of the bit string is obtained and multicast data message 4 is obtained. PE5 sends multicast data message 4 to receiver 2 to complete BIER traffic forwarding.

Step 5-1: Intermediate link failure

For example, Figure 27 shows the scenario where the link between PE3 and PE5 fails. When the link fails, PE3 receives multicast data packet 2 and searches for BIFT. It can still obtain the label arriving at BFR-ID 5. is 30, the BFR neighbor is PE6, and the outbound interface is interface 3, then PE3 forwards multicast data packet 3 based on multicast data packet 2 to PE6 through interface 3. For example, Table 25 shows the entries in the BIFT table of PE3. The BIFT index in PE3 is <SD:1,SI:1,BSL:64>.

Table 25

Step 5-2: Intermediate node failure

Figure 28 shows a node failure scenario, for example, PE3 fails. PE1 receives multicast data packet 1, adds a header containing a bit string to multicast data packet 1, and obtains multicast data packet 2. The bit string contains the destination BFER that the packet needs to reach, that is, the BFR-ID of PE5. The bit string is 010000. The BIFT on PE1 is shown in Table 26 below. When PE1 sends multicast data packet 2, it sends multicast data packet 2 from the egress interface directly connected to PE4 according to the BIFT shown in Table 26.

Table 26

After PE4 receives multicast data packet 2, PE4 obtains multicast data packet 3 based on multicast data packet 2 and the BIFT shown in Table 27 below, and sends multicast data packet 3 from the interface directly connected to PE5. . The bit string in multicast data message 3 is obtained from the bit string in multicast data message 2 and F-BM 110000.

Table 27

Step 6: Internal packet forwarding within the site.

When multicast data packet 3 arrives at PE6, PE6 looks up the BIFT shown in Table 28. After comparison, it is concluded that the next hop label is 31. PE6 obtains multicast data packet 4 based on multicast data packet 3 and Table 28. , sending multicast data packet 4 through outbound interface 4, so that multicast data packet 4 is forwarded to PE5.

At this time, even if the intermediate link fails, the end-to-end packet forwarding process can still continue, and there is no need to perform route convergence after the failure, and the packets arriving on PE3 will not be discarded because route convergence has not been completed.

Table 28

The following describes the embodiment with reference to the BIER-MPLS scenario shown in Figure 29. In the scenario shown in Figure 29, PE3 and PE6 have no direct link.

As shown in Figure 29, the root node of multicast is site 1 directly connected to the multicast source. The multicast leaf node is site 3 to which the multicast receiver is directly connected. Site 2 represents the intermediate device. Both the root node and the leaf node enable the BIER capability, serve as BFR nodes, and assign BFR IDs. In this example, site 1 and site 3 serve as BFIR and BFER respectively. Interface 1 is the outbound interface from PE3 to PE4, and interface 2 is the outbound interface from PE3 to PE5. Interface 3 is the outbound interface from PE4 to PE6, and interface 4 is the outbound interface from PE6 to PE5.

The difference compared with the previous scenario is that there is no direct link between PE3 and PE6. For the scenario shown in Figure 41, the embodiment includes the following steps 1 to 5.

Step 1. Deploy BIER-MPLS

The root node, leaf nodes and intermediate nodes are uniformly configured with BIER sub-domain ID of 1, BSL of 64 and SI of 1. The BFR-ID of each device in the root node and each leaf node is different; the intermediate node is not configured with BFR-ID, but supports BIER forwarding.

Two devices in the same site are deployed with IGP BIER, and the two devices in the site establish BIER forwarding tables. Packets can be forwarded through BIER in the site. Enable BGP between different sites to enable global routing and forwarding functions. For example, refer to Table 29 below, which shows the parameters configured on each device.

Table 29

Step 2: Announce the parameter set of BIER and generate BIFT.

Each device floods the BIER parameter set in the BIER subdomain through the deployed IGP. Each device generates a BIER routing table and a BIER forwarding table based on the received parameter set. Since the link from PE3 to PE5 is better than the link from PE3 to PE6, PE3 uses PE5 as the BFR-NBR. There is only one outbound interface in the BIFT table.

The BIFT table generated on PE3 is shown in Table 30 below.

Table 30

The BIFT table generated on PE4 is shown in Table 31 below.

Table 31

PE5 generates the BIFT table shown in Table 32 below based on the bypass BIER-MPLS label, and PE6 generates the BIFT table shown in Table 33 below based on the bypass BIER-MPLS label.

Table 32

Table 33

Step 3: Forward the multicast data packet.

The root node sends multicast data message 1. The destination recipient of multicast data message 1 is receiver 2 of the PE5 connection corresponding to BFR-ID 5.

After PE1 receives multicast data packet 1, it adds a header containing a bit string to multicast data packet 1 and obtains multicast data packet 2. The bit string contains the BFR-ID of the destination BFER that the message needs to reach, and the bit string is 010000. Based on the comparison result between the bit string and the F-BM in BIFT on PE1, PE1 determines that the next hop label is 20 and the outbound interface is the interface pointing to PE3 or PE4. When there are two outgoing interfaces on PE1 to reach the current neighbor, PE1 selects one of them to forward multicast data packet 2.

When PE1 sends multicast data message 2 through the interface pointing to PE3, after PE3 receives multicast data message 2, PE3 compares the bit string in multicast data message 2 with BIFT, and obtains the next hop label as 30. Obtain multicast data packet 3 based on multicast data packet 2 and BIFT, and send multicast data packet 3 from the outbound interface pointing to PE5.

After multicast data packet 3 reaches PE5, PE 5 compares the bit string in multicast data packet 3 with the BIFT on PE 5 and finds that the local machine is the destination device, so it decapsulates the multicast data packet 3 containing The message header of the bit string is obtained, and multicast data message 4 is obtained to complete BIER traffic forwarding.

Step 4-1: Intermediate link failure

Figure 30 shows a link failure scenario. As shown in Figure 30, when the link between PE3 and PE5 fails. PE3 converges BFR-NBR to PE4, and PE3 uses the local interface directly connected to PE4 as the outbound interface, resulting in the BIFT shown in Table 34.

Table 34

On PE4, there is a forwarding entry to PE6, so the forwarding path from PE3 to PE6 can be opened. The forwarding path between PE3 and BFR-ID5 is connected by the route from PE6 to PE5 in the site.

When PE3 updates the outbound interface from interface 2 to interface 1, it is faster than the non-anycast scenario. After converging to PE4, the route to PE6 is directly used, and no microloop occurs.

In the non-anycast scenario, when each device does not use anycast label, the same fault occurs. After PE3 updates the outgoing interface to interface 1, PE4 still uses PE5 as the destination to learn neighbors, and the route to PE5 is not like anycast. In this scenario, you can choose a route directly in the direction of PE6. PE4 may not realize that [PE3-PE5] is blocked, and still thinks that [PE4-PE3-PE5] and [PE4-PE6-PE5] are optional paths. When PE4 selects PE3 as the next hop to PE5, a microloop occurs. The above-mentioned micro-loop behavior may occur more than once, which will cause continuous packet loss after a link failure until the micro-loop behavior stops.

Therefore, using anycast label can avoid micro-loop problems after link failures, speed up link convergence and routing switching, and achieve the purpose of rapid traffic protection.

Step 4-2: Intermediate node failure

Taking the failure of PE3 as an example, as shown in Figure 31, before PE3 fails, the BIFT on PE1 is as shown in Table 35 below. After PE3 fails, the BIFT on PE1 is as shown in Table 36 below. PE1 receives multicast data packet 1 from the multicast source, adds a header containing a bit string to multicast data packet 1, and obtains multicast data packet 2. The bit string in the packet header is 010000. When PE1 forwards the packet, PE1 sends multicast data packet 2 from the egress interface directly connected to PE2 according to the BIFT shown in Table 36.

Table 35

Table 36

When multicast data packet 2 arrives at PE4, PE4 obtains multicast data packet 3 based on the BIFT and multicast data packet 2 shown in Table 37. PE4 forwards the multicast data packet from the interface directly connected to PE6. 3.

Table 37

Step 5: Internal packet forwarding within the site.

When multicast data packet 3 reaches PE6, PE6 searches for BIFT shown in Table 38 according to the bit string in the header of multicast data packet 3, and after comparison, it is concluded that the next hop label is 31. PE6 obtains multicast data packet 4 according to multicast data packet 3. PE6 sends multicast data packet 4 through the direct interface with PE5, so that multicast data packet 4 is forwarded to PE5.

Table 38

The embodiment will be described below with reference to the scenario shown in FIG. 32 as an example.

Figure 32 shows a networking scenario where BIERv6PE3 and PE6 have direct links.

In the scenario shown in Figure 32, the multicast root node is headquarters site 1 directly connected to the multicast source. The multicast leaf node is the site 3 to which the multicast receiver is directly connected. Site 2 represents the intermediate node. Both the multicast source and receiver enable the BIERv6 capability, serve as BFR nodes, and assign BFRIDs. In this example, site 1 and site 3 serve as BFIR and BFER respectively. Interface 1 is the outbound interface from PE3 to PE4, interface 2 is the outbound interface from PE3 to PE5, and interface 3 is the outbound interface from PE3 to PE6.

This embodiment includes the following steps 1 to 6.

Step 1: Deploy BIERv6

PE1 to PE6 are uniformly configured with BIER sub-domain ID 1, BSL 64, and SI 1. The BFR-ID of the root node and leaf nodes are different; the intermediate nodes are not configured with BFR-ID, but support BIERv6 forwarding;

Two devices at the same site are configured with the same anycast End.BIER and different bypass End.BIER; different sites are configured with different anycast End.BIER.

Two devices in the same site are deployed with IGP BIER, and the two devices in the site establish BIERv6 forwarding tables. Packets can be forwarded in the site through BIERv6. Table 39 shows the parameters configured on each device.

Table 39

Step 2: Flood BIER’s parameter set.

Each device in the BIER subdomain floods the BIER parameter set through the deployed IGP. Each device generates F-BM based on the received BFR-ID.

PE3 receives the BIERv6 information sub-TLV from PE5 and PE6. The BIERv6 information sub-TLV contains the sub-sub-TLV carrying End.BIER. The BIERv6 information sub-TLV sent by PE5 is shown in Figure 33. The BIERv6 information sub-TLV sent by PE6 is shown in Figure 34. PE3 parses bypass End.BIER and anycast End.BIER in sub-sub-TLVs. PE3's anycast End.BIER is 2::1 and bypass End.BIER is 2::2. When PE3 parses out that PE5's anycast End.BIER is 3::1, which is inconsistent with PE3's own anycast End.BIER, PE3 records 3::1 as the current <sub-domain, SI, BSL> in BFR- Next hop End.BIER of ID 5. In the same way, the next hop End.BIER from PE3 to BFR-ID 6 is also 3::1.

PE6 receives the BIERv6 information sub-TLV of PE5 and parses the sub-sub-TLV in the BIERv6 information sub-TLV. When the parsed anycast End.BIER is 3::1, it is consistent with the local anycast End.BIER. The parsed bypass End.BIER is 3::2, then the bypass End.BIER3::2 is recorded as the next hop End.BIER to BFR-ID 5 in the current <sub-domain, SI, BSL>.

Step 3: Generate BIFT table.

Since the link from PE3 to PE5 and the link from PE3 to PE6 are equal-cost links, PE3 uses both PE5 and PE6 as BFR-NBR and reflects their outbound interfaces and next hops in the BIFT table. The BIFT table generated on PE3 is shown in Table 40.

Table 40

PE5 generated the BIFT table shown in Table 41 based on the parsed bypass BIER-MPLS label, and PE6 generated the BIFT table shown in Table 42 based on the parsed bypass BIER-MPLS label.

Table 41

Table 42

Step 4: Forward the multicast data packet.

The root node sends multicast data packet 1. The destination recipient of multicast data packet 1 is multicast receiver 2 connected to PE5 with BFR-ID 5.

When PE1 receives multicast data packet 1, PE1 adds a header containing a bit string and End.BIER SID to multicast data packet 1 to obtain multicast data packet 2. The bit string in the message header contains the BFR-ID of the destination BFER that the message needs to reach, and the bit string is 010000.

Based on the comparison result between the bit string and the F-BM in BIFT on PE1 as shown in Table 43, PE1 determines that the outbound interface is the interface pointing to PE3 or PE4. When the current neighbor has two outgoing interfaces, PE1 selects one of the outgoing interfaces to send multicast data packet 2. Both interfaces may be used to forward multicast data packet 2.

Table 43

When multicast data packet 2 is forwarded from the interface on PE1 that points to PE3, PE3 receives multicast data packet 2. PE3 compares the bit string in the header of multicast data packet 2 with the F-BM in the BIFT, and finds that the neighbor is PE5. Then PE2 forwards the multicast obtained based on multicast data packet 2 from the outgoing interface pointing to PE5. Data message 3.

Table 44

After multicast data packet 3 arrives at PE5, PE5 compares the bit string in the header of multicast data packet 3 with PE5's BIFT. PE5 finds that this device is the destination device, so it strips off the header containing the bit string of multicast data packet 3 and forwards the obtained multicast data packet 4 to multicast receiver 2, completing BIER traffic forwarding.

Step 5-1: The intermediate link fails.

Figure 35 shows a link failure scenario. As shown in Figure 35, the link between PE3 and PE5 fails. At this time, when PE3 receives multicast data message 2, PE3 looks up the BIFT shown in table 45 and concludes that the next hop is PE5 or PE6. At this time, because the outbound interface 2 of PE3 reaching PE6 is no longer available due to a link failure, Then PE3 uses interface 3 reaching PE5 to forward multicast data packet 3 obtained based on multicast data packet 2 to PE6.

Table 45

Step 5-2: Intermediate node failure.

Taking the failure of PE3 as an example, PE1 obtains multicast data packet 2 based on multicast data packet 1 from the multicast source. The bit string in the header of multicast data packet 2 is 010000. When PE1 forwards multicast data packet 2 according to the BIFT shown in Table 47, it forwards multicast data packet 2 from the outbound interface directly connected to PE4.

Table 46

When multicast data packet 2 arrives at PE4, PE4 obtains multicast data packet 3 based on multicast data packet 2 and the BIFT entry shown in Table 47, from the interface directly connected to PE5 and to PE6. One of the interfaces sends multicast data packet 3, so that multicast data packet 3 reaches the destination site.

Table 47

Step 6: Internal packet forwarding within the site.

When the multicast data packet 3 reaches PE6, PE6 looks up the BIFT shown in table 48 based on the bit string in the header of the multicast data packet 3, and compares the bit string with the F-BM in the BIFT. The outgoing next hop End.BIER is 3::2, and PE6 forwards the multicast data packet obtained based on multicast data packet 3 from outgoing interface 4 to PE5.

At this time, even if the intermediate link fails, the end-to-end packet forwarding process can still continue. And there is no need to perform road maintenance after a failure. Due to convergence, packets arriving on PE3 will not be discarded because routes have not completed convergence.

Table 48

The following is an example of the networking scenario shown in Figure 37. Figure 37 is a specific example where BIERv6PE3 and PE6 have no direct link. As shown in Figure 37, the multicast root node is site 1 directly connected to the multicast source. The multicast leaf node is the site 3 to which the multicast receiver is directly connected. Site 2 represents the intermediate device.

Both the multicast source and receiver enable the BIERv6 capability, serve as BFR nodes, and assign BFR-IDs. In this example, site 1 and site 3 serve as BFIR and BFER respectively. Interface 1 is the outbound interface from PE3 to PE4, and interface 2 is the outbound interface from PE3 to PE5. Interface 3 is the outbound interface from PE4 to PE6. Interface 4 is the outbound interface from PE6 to PE5.

In the scenario shown in Figure 37, the embodiment includes the following steps 1 to 6.

Step 1: Deploy BIERv6.

PE1 to PE6 are uniformly configured with BIER sub-domain ID 1, BSL 64, and SI 1. The BFR-ID of each device on the root node and leaf node is different; the intermediate node is not configured with BFR-ID, but supports BIERv6 forwarding.

Two devices at the same site are configured with the same anycast End.BIER SID and different bypass End.BIER SID. Different sites configure different anycast End.BIER SID. Table 49 shows the parameters configured on each device.

Two devices in the same site are deployed with IGP BIER, and the two devices in the site establish BIERv6 forwarding tables. Packets can be forwarded in BIERv6 within the site.

Table 49

Step 2: Announce BIERv6 information and generate BIFT.

Each device floods the BIER parameter set in the BIER subdomain through the deployed IGP. Each device generates a BIER routing table and a BIER forwarding table based on the received BIER parameter set.

PE3 receives the BIERv6 information sub-TLV of PE5 and PE6. The sub-TLV contains the sub-sub-TLV carrying End.BIER. The BIERv6 information sub-TLV sent by PE 5 is shown in Figure 38, and the BIERv6Info sub-TLV sent by PE6 is shown in Figure 39.

PE3 parses bypass End.BIER and anycast End.BIER in sub-sub-TLV. PE3's anycast End.BIER is 2::1 and bypass End.BIER is 2::2. When the anycast End.BIER of PE5 is parsed out to be 3::1, it is different from my own anycast End.BIER. If so, record 3::1 as the next hop End.BIER to BFR-ID 5 in the current <sub-domain, SI, BSL>. Similarly, the next hop End.BIER from PE3 to BFR-ID6 is also 3::1.

PE6 receives the BIERv6Info of PE5 and parses the sub-sub-TLV. When the parsed anycast End.BIER is 3::1, it is consistent with the local anycast End.BIER, and the parsed bypass End.BIER is 3::2. , then record 3::2 as the next hop End.BIER to BFR-ID 5 in the current <sub-domain, SI, BSL>.

Step 3: BIFT table and routing generation.

Since PE3 to PE5 and PE3 to PE6 are not equal-cost routes, and the route to PE5 is better, the interface directly connected from PE3 to PE5 is used as the outbound interface. The BIFT table generated on PE3 is shown in Table 50 below.

Table 50

PE5 generates a BIFT table based on the parsed bypass BIER-MPLS label as shown in Table 51 below.

PE6 generates a BIFT table based on the parsed bypass BIER-MPLS label as shown in Table 52 below.

Table 51

Table 52

Step 4: Forward the multicast data packet.

The multicast source sends multicast data packet 1, and the destination recipient of multicast data packet 1 is receiver 2 of the PE5 connection corresponding to BFR-ID 5.

After PE1 receives multicast data message 1, it encapsulates the message header containing the bit string and End.BIER SID into multicast data message 1, and obtains multicast data message 2. The bit string in the message header contains the destination BFR-ID that the message needs to reach, and the bit string is 010000. Based on the comparison result between the bit string and the F-BM in BIFT on PE1, PE 1 concludes that the BFR-neighbor is 2::1. PE1 searches the forwarding table and finds that the outgoing interface is the interface pointing to PE3 or PE4. When there are two outgoing interfaces arriving at the current neighbor, one of them is selected to send multicast data packet 2. Both interfaces may be used to forward multicast data packets 2.

When multicast data packet 2 is forwarded from the interface pointing to PE3, after PE3 receives multicast data packet 2, PE3 compares the bit string in multicast data packet 2 with BIFT to obtain the neighbor's End.BIER. The SID is 3::1, and multicast data packet 3 obtained based on multicast data packet 2 is sent through the outbound interface pointing to PE5.

After multicast data packet 3 reaches PE5, PE5 compares the bit string in multicast data packet 3 with PE5's BIFT. PE5 finds that the local machine is the destination device, and then decapsulates the bit string contained in multicast data packet 3. And the message header of End.BIER SID, obtain the multicast data message 4, send the multicast data message 4 to the receiver 2, and complete the BIER traffic forwarding.

Step 5-1: The intermediate link fails.

Figure 40 shows a link failure scenario. The link between PE3 and PE5 fails. At this time, PE3 has reached PE3 The bit string in the multicast data packet 2 is searched for BIFT and the next hop End.BIER is 3::1. However, the entry to PE5 in the BIER forwarding table is no longer available, so it needs to be converged to PE4 again. The outbound interface on PE3 that reaches the BFR neighbor PE4 is 3, so PE3 uses interface 3 to forward the multicast data packet 3 obtained based on the multicast data packet 2 to PE6.

Step 5-2: Intermediate node failure.

Figure 41 shows a node failure scenario, taking the failure of PE3 as an example. Before PE3 fails, the BIFT on PE1 is as shown in Table 53. After PE3 fails, the BIFT on PE1 is as shown in Table 54. Then PE1 obtains multicast data packet 2 based on multicast data packet 1 from the multicast source, and the bit string in multicast data packet 2 is 010000. When PE1 forwards multicast data packet 2, it sends multicast data packet 2 from the outbound interface directly connected to PE2 as shown in Table 53. After PE2 receives multicast data packet 2, PE2 searches for PE2's BIFT based on the bit string of multicast data packet 2 and obtains multicast data packet 3. PE2 sends multicast data packet 3 to PE4.

Table 53

Table 54

After PE3 fails, the BIFT on PE4 is as shown in Table 55. When multicast data packet 3 arrives at PE4, PE4 forwards multicast data packet 4 based on multicast data packet 3 from the interface directly connected to PE6.

Table 55

Step 6: Internal packet forwarding within the site.

After multicast data packet 4 reaches PE6, PE6 searches for the BIFT shown in Table 56 below based on the bit string in the header of multicast data packet 4. After comparing the bit string and F-BM, PE6 obtains the next hop. End.BIER is 3::2, and PE6 sends multicast data packet 5 based on multicast data packet 4 to PE5 from outbound interface 4.

Table 56

At this time, even if the intermediate link fails, the end-to-end packet forwarding process can still continue. There is no need to perform route convergence after a fault, and multicast data packets arriving on PE3 will not be discarded because routes have not completed convergence.

FIG42 is a schematic diagram of a structure of a corresponding relationship acquisition device 700 provided in an embodiment of the present application. The corresponding relationship acquisition device 700 is arranged in a second forwarding device in a second site, and includes a receiving unit 701 and a processing unit 702.

The receiving unit 701 is configured to receive the first parameter set from the first forwarding device in the first site, where the first parameter set includes the first anycast label, the BFR-ID of the first forwarding device, and the BFR prefix of the first forwarding device, The first anycast label is used to identify the first site; the receiving unit 701 is also used to receive a second parameter set from the third forwarding device in the first site. The second parameter set includes the second anycast label, the third The BFR-ID of the third forwarding device and the BFR prefix of the third forwarding device, and the second anycast label is used to identify the first site;

The processing unit 702 is configured to obtain a first corresponding relationship based on the first parameter set and the BFR-ID of the third forwarding device. The first corresponding relationship includes matching the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device. The forwarding bit mask F-BM, the first anycast label and the next hop matching the BFR prefix of the first forwarding device; the processing unit 702 is also configured to based on the second parameter set and the BFR-ID of the first forwarding device Obtain a second correspondence relationship, which includes an F-BM that matches the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device, a second anycast label, and a BFR prefix that matches the third forwarding device. the next hop.

In some embodiments, the processing unit 702 is used to determine that the first forwarding device and the third forwarding device belong to the first site based on the first anycast label and the second anycast label; obtain the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device; obtain a first corresponding relationship based on the F-BM, the first anycast label and the BFR prefix of the first forwarding device, and the first corresponding relationship includes the F-BM, the first anycast label and the BFR prefix of the first forwarding device.

In some embodiments, the processing unit 702 is used to determine that the first forwarding device and the third forwarding device belong to the first site based on the first anycast label and the second anycast label; obtain the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device; determine the first outbound interface on the second forwarding device to reach the first forwarding device based on the BFR prefix of the first forwarding device; obtain a first correspondence based on the F-BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outbound interface, the first correspondence including the F-BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outbound interface.

In some embodiments, the processing unit 702 is configured to determine based on the first anycast label and the second anycast label that both the first forwarding device and the third forwarding device belong to the first site; based on the BFR-ID of the first forwarding device and The BFR-ID of the third forwarding device is used to obtain F-BM; based on the F-BM, the second anycast label and the BFR prefix of the third forwarding device, the second corresponding relationship is obtained. The second corresponding relationship includes F-BM, the second Anycast label and BFR prefix of the third forwarding device.

In some embodiments, the processing unit 702 is configured to determine based on the first anycast label and the second anycast label that both the first forwarding device and the third forwarding device belong to the first site; based on the BFR-ID of the first forwarding device and Obtain the F-BM based on the BFR-ID of the third forwarding device; determine the second outbound interface on the second forwarding device to the third forwarding device based on the BFR prefix of the third forwarding device; based on the F-BM and the second anycast label , the BFR prefix of the third forwarding device and the second outgoing interface, and obtain a second corresponding relationship. The second corresponding relationship includes the F-BM, the second anycast label, the BFR prefix of the third forwarding device and the second outgoing interface.

In some implementations, both the first anycast label and the second anycast label are labels; or, the first anycast label and the second anycast label are both IPv6 destination addresses.

In some embodiments, the first parameter set further includes one or more of the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the identifier of the BIER subdomain where the first forwarding device is located. ;

The second parameter set also includes one or more of the bit string length BSL of the third forwarding device, the set identifier SI to which the third forwarding device belongs, and the identifier of the BIER subdomain in which the third forwarding device is located.

In some embodiments, the receiving unit 701 is configured to receive a first advertisement message from the first forwarding device, the first advertisement message includes a BIER information sub-TLV, and the BIER information sub-TLV includes a first anycast label; receiving the first advertisement message from the first forwarding device. The second advertisement message of the first forwarding device in a site, the second advertisement message includes the BIER information sub-TLV, and the BIER information sub-TLV includes the second anycast label.

In some implementations, the first advertisement message and the second advertisement message are IGP messages; or the first advertisement message and the second advertisement message are BGP messages.

In some embodiments, the first forwarding device is a BFER and the second forwarding device is a transit BFR; or, the first forwarding device is a transit BFR and the second forwarding device is a BFIR; or, the first forwarding device and the second forwarding device are adjacent transit BFRs.

In some implementations, the processing unit 702 is also configured to: obtain a first BIER message, where the first BIER message includes a first bit string, The label of the second forwarding device and the multicast data message, the first bit string corresponds to one or more of the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device; based on the first BIER message and The first correspondence relationship obtains the second BIER message. The second BIER message includes the second bit string, the first anycast label and the multicast data message. The second bit string is based on the first bit string and the first correspondence relationship. obtained by the F-BM; the device further includes: a sending unit, used to send the second BIER message.

In some embodiments, the sending unit is configured to, if the next hop matching the BFR prefix of the first forwarding device is in a fault state, send a message to the next hop matching the BFR prefix of the third forwarding device in the second correspondence relationship. The second BIER message; or, if the next hop matching the BFR prefix of the third forwarding device is in a fault state, send the second BIER message to the next hop matching the BFR prefix of the first forwarding device in the first correspondence relationship. message; or, if neither the next hop matching the BFR prefix of the first forwarding device nor the next hop matching the BFR prefix of the third forwarding device is in a fault state, forwarding the message to the next hop matching the BFR prefix of the first forwarding device. The next hop with the smallest link cost and the next hop that matches the BFR prefix of the third forwarding device sends the second BIER message; or, if the next hop that matches the BFR prefix of the first forwarding device and the next hop with the smallest link cost, the second BIER message is sent. None of the next hops matching the BFR prefix of the third forwarding device are in a fault state, and the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device are in the link network. The one with the highest quality sends the second BIER message; or, if the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device are not in a fault state, send the second BIER message to the Either one of the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device sends the second BIER message.

The device embodiment described in Figure 42 is only illustrative. For example, the division of the above units is only a logical function division. In actual implementation, there may be other divisions. For example, multiple units or components may be combined or may be Integrated into another system, or some features can be ignored, or not implemented. Each functional unit in various embodiments of the present application can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

Each unit in the correspondence relationship acquisition device 700 is implemented in whole or in part by software, hardware, firmware, or any combination thereof.

The following describes some possible implementations of each functional unit in the acquisition device 700 using hardware or software to implement the corresponding relationship in conjunction with the hardware device 900 described below.

In the case of software implementation, for example, the above-mentioned processing unit 702 is implemented by a software functional unit generated by at least one processor 901 in FIG. 44 after reading the program code stored in the memory 902.

In the case of hardware implementation, for example, the above-mentioned units in Figure 42 are respectively implemented by different hardware in the forwarding device. For example, the processing unit 702 is implemented by a part of the processing resources (such as multi-core) in at least one processor 901 in Figure 44 One core or two cores in the processor), or using programmable devices such as field-programmable gate array (FPGA) or co-processor. The receiving unit 701 is implemented by the network interface 903 in Figure 44.

Figure 43 is a schematic structural diagram of a parameter notification device 800 provided by an embodiment of the present application. The device 800 is located on the first forwarding device in the first site and includes: a processing unit 801 for obtaining the first parameter set, the first parameter The set includes a first anycast label, a BFR-ID of the first forwarding device and a BFR prefix of the first forwarding device. The first anycast label is used to identify the first site; the sending unit 802 is used to send a message to the second site in the second site. The forwarding device sends the first parameter set.

In some embodiments, the first parameter set further includes one or more of the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the identifier of the BIER subdomain where the first forwarding device is located. .

In some implementations, the sending unit 802 is configured to send a first notification message to the second forwarding device, where the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes a first anycast label.

In some implementations, the first forwarding device is a BFER and the second forwarding device is a transit BFR; or the first forwarding device is a transit BFR and the second forwarding device is a BFIR; or the first forwarding device and the second forwarding device are Adjacent transit BFR.

In some implementations, the apparatus further includes: a receiving unit configured to receive a third parameter set from a third forwarding device in the first site, where the third parameter set includes a first bypass label, a BFR-ID of the third forwarding device, and BFR prefix of the third forwarding device, the first bypass label is used to identify the third forwarding device;

The processing unit 801 is also configured to obtain a third correspondence based on the third parameter set. The third correspondence includes the first bypass tag, the F-BM matching the BFR-ID of the third forwarding device, and the BFR of the third forwarding device. The next hop that prefix matches.

In some embodiments, the receiving unit is also configured to receive a first BIER message, where the first BIER message includes a first bit string corresponding to the BFR-ID of the third forwarding device, a first anycast label, and a multicast datagram. The processing unit 801 is also configured to obtain a second BIER message based on the first BIER message and the third corresponding relationship. The second BIER message includes the second bit string, the first bypass label and the multicast data message. The two-bit string is a bit string obtained based on the F-BM in the first bit string and the third corresponding relationship; the sending unit 802 is also used to send the second BIER message to the third forwarding device.

In some embodiments, the processing unit 801 is also used to obtain a fourth parameter set. The fourth parameter set includes the second bypass label, the BFR-ID of the first forwarding device, and the BFR prefix of the first forwarding device. The second bypass label Used to identify the first forwarding device; the sending unit 802 is also used to send the fourth parameter set to the third forwarding device.

The device embodiment described in Figure 43 is only illustrative. For example, the division of the above units is only a logical function division. In actual implementation, there may be other divisions. For example, multiple units or components may be combined or may be Integrated into another system, or some features can be ignored, or not implemented. Each functional unit in various embodiments of the present application can be integrated into one processing unit 801, or each unit can exist physically alone, or two or more units can be integrated into one unit.

Each unit in the parameter notification device 800 is implemented in whole or in part by software, hardware, firmware, or any combination thereof.

Some possible implementations of using hardware or software to implement each functional unit in the parameter notification device 800 are described below in conjunction with the hardware device 900 described below.

In the case of software implementation, for example, the above-mentioned processing unit 801 is implemented by a software functional unit generated by at least one processor 901 in FIG. 44 after reading the program code stored in the memory 902.

In the case of hardware implementation, for example, the above-mentioned units in Figure 43 are respectively implemented by different hardware in the forwarding device. For example, the processing unit 801 is implemented by a part of the processing resources (such as multi-core) in at least one processor 901 in Figure 44 One core or two cores in the processor), or using programmable devices such as field-programmable gate array (FPGA) or co-processor. The sending unit 802 is implemented by the network interface 903 in Figure 44.

Figure 44 is a schematic structural diagram of a forwarding device 900 provided by an embodiment of the present application.

The forwarding device 900 includes at least one processor 901, a memory 902, and at least one network interface 903.

The processor 901 is, for example, a general central processing unit (CPU), a network processor (NP), a graphics processing unit (GPU), or a neural network processor (neural-network processing units, NPU). ), a data processing unit (DPU), a microprocessor or one or more integrated circuits used to implement the solution of the present application. For example, the processor 901 includes an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. PLD is, for example, a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a general array logic (GAL), or any combination thereof.

The memory 902 is, for example, a read-only memory (ROM) or other type that can store static information and instructions. Static storage devices, such as random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or electrically erasable programmable read-only memory (electrically erasable programmable read-only memory, EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), disk storage media or other magnetic disks A 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, but is not limited thereto. Optionally, the memory 902 exists independently and is connected to the processor 901 through an internal connection 904. Alternatively, memory 902 and processor 901 may optionally be integrated together.

Network interface 903 uses any transceiver-like device for communicating with other devices or communications networks. The network interface 903 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 (WLAN) interface, a cellular network network interface or a combination thereof.

In some embodiments, processor 901 includes one or more CPUs, such as CPU0 and CPU1 shown in Figure 44.

In some embodiments, forwarding device 900 optionally includes multiple processors, such as processor 901 and processor 905 shown in Figure 44. Each of these processors is, for example, a single-core processor (single-CPU) or a multi-core processor (multi-CPU). Processor here optionally refers to one or more devices, circuits, and/or processing cores for processing data (eg, computer program instructions).

In some embodiments, forwarding device 900 also includes an internal connection 904. The processor 901, the memory 902 and at least one network interface 903 are connected through an internal connection 904. Internal connections 904 include pathways that carry information between the components described above. Optionally, internal connection 904 is a single board or bus. Optionally, the internal connections 904 are divided into address bus, data bus, control bus, etc.

In some embodiments, the forwarding device 900 also includes an input and output interface 906. Input/output interface 906 is connected to internal connection 904 .

Optionally, the processor 901 implements the method in the above embodiment by reading the program code stored in the memory 902, or the processor 901 implements the method in the above embodiment by using the internally stored program code. In the case where the processor 901 implements the method in the above embodiment by reading the program code stored in the memory 902, the memory 902 stores the program code 910 that implements the method provided by the embodiment of the present application.

For more details on how the processor 901 implements the above functions, please refer to the descriptions in the previous method embodiments, which will not be repeated here.

Each embodiment in this specification is described in a progressive manner. The same and similar parts between the various embodiments can be referred to each other. Each embodiment focuses on its differences from other embodiments.

A refers to B, which means that A is the same as B or that A is a simple transformation of B.

The terms "first" and "second" in the description and claims of the embodiments of this application are used to distinguish different objects, rather than to describe a specific order of objects, and cannot be understood to indicate or imply relative importance. sex. For example, the first correspondence relationship and the second correspondence relationship are used to distinguish different correspondence relationships, but are not used to describe a specific order of the correspondence relationships, nor can it be understood that the first correspondence relationship is more important than the second correspondence relationship.

In the embodiments of this application, unless otherwise stated, “at least one” means one or more, and “plurality” means two or more. For example, multiple correspondences refer to two or more correspondences.

The above embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. A computer program product includes one or more computer instructions. When computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with the embodiments of the present application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable device. Computer instructions may be stored in a computer-readable In a storage medium, or from one computer-readable storage medium to another computer-readable storage medium, for example, computer instructions may be transmitted from a website, computer, server, or data center over wires (e.g., coaxial cables, optical fiber, digital subscriber (DSL)) or wireless (such as infrared, wireless, microwave, etc.) to another website, computer, server or data center. Computer-readable storage media can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or other integrated media that contains one or more available media. Available media may be magnetic media (eg, floppy disk, hard disk, magnetic tape), optical media (eg, DVD), or semiconductor media (eg, Solid State Disk (SSD)), etc.

The above embodiments are only used to illustrate the technical solutions of the present application, but are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments. Modifications may be made to the recorded technical solutions, or equivalent substitutions may be made to some of the technical features; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the scope of the technical solutions of the embodiments of the present application.

Claims

A method for obtaining a correspondence relationship, which is characterized by including:

The second forwarding device in the second site receives the first parameter set from the first forwarding device in the first site. The first parameter set includes the first anycast tag, the BFR-ID of the first forwarding device and the BFR prefix of the first forwarding device, the first anycast label is used to identify the first site;

The second forwarding device receives a second parameter set from a third forwarding device in the first site, the second parameter set including a second anycast label, a BFR-ID of the third forwarding device, and a BFR prefix of the third forwarding device, the second anycast label being used to identify the first site;

The second forwarding device obtains a first corresponding relationship based on the first parameter set and the BFR-ID of the third forwarding device. The first corresponding relationship includes the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device. The forwarding bit mask F-BM matched by the BFR-ID of the third forwarding device, the first anycast label and the next hop matching the BFR prefix of the first forwarding device;

The second forwarding device obtains a second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device. The second corresponding relationship includes the BFR-ID of the first forwarding device and the BFR-ID of the first forwarding device. The F-BM that matches the BFR-ID of the third forwarding device, the second anycast label, and the next hop that matches the BFR prefix of the third forwarding device.
The method of claim 1, wherein the second forwarding device obtains the first correspondence based on the first parameter set and the BFR-ID of the third forwarding device, including:

The second forwarding device determines that the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag;

The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

The second forwarding device obtains the first corresponding relationship based on the F-BM, the first anycast label and the BFR prefix of the first forwarding device, and the first corresponding relationship includes the F- BM, the first anycast label and the BFR prefix of the first forwarding device.
The method of claim 1, wherein the second forwarding device obtains the first correspondence based on the first parameter set and the BFR-ID of the third forwarding device, including:

The second forwarding device determines that the first forwarding device and the third forwarding device belong to the first site based on the first anycast tag and the second anycast tag;

The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

The second forwarding device determines the first outbound interface on the second forwarding device that reaches the first forwarding device based on the BFR prefix of the first forwarding device;

The second forwarding device obtains the first corresponding relationship based on the F-BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outbound interface. The corresponding relationship includes the F-BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outbound interface.
The method according to any one of claims 1 to 3, characterized in that the second forwarding device obtains the second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device, including:

The second forwarding device determines that the first forwarding device and the third forwarding device both belong to the first site based on the first anycast tag and the second anycast tag;

The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

The second forwarding device obtains the second correspondence based on the F-BM, the second anycast label and the BFR prefix of the third forwarding device, and the second correspondence includes the F-BM, the second anycast label and the BFR prefix of the third forwarding device.
The method according to any one of claims 1 to 3, characterized in that the second forwarding device obtains the second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device, including:

The second forwarding device determines the first forwarding device and the first anycast tag based on the first anycast tag and the second anycast tag. The third forwarding devices all belong to the first site;

The second forwarding device obtains the F-BM based on the BFR-ID of the first forwarding device and the BFR-ID of the third forwarding device;

The second forwarding device determines the second outbound interface on the second forwarding device that reaches the third forwarding device based on the BFR prefix of the third forwarding device;

The second forwarding device obtains the second corresponding relationship based on the F-BM, the second anycast label, the BFR prefix of the third forwarding device, and the second outbound interface. The corresponding relationship includes the F-BM, the second anycast label, the BFR prefix of the third forwarding device, and the second outbound interface.
The method according to any one of claims 1 to 5, characterized in that the first anycast tag and the second anycast tag are both tags; or

The first anycast label and the second anycast label are both IPv6 destination addresses.
The method according to any one of claims 1 to 6, characterized in that the first parameter set further includes a bit string length BSL of the first forwarding device, a set identifier SI to which the first forwarding device belongs. and one or more identifiers of the BIER subdomain where the first forwarding device is located;

The second parameter set further includes one of the bit string length BSL of the third forwarding device, the set identifier SI to which the third forwarding device belongs, and the identifier of the BIER subdomain where the third forwarding device is located, or Multiple.
The method according to any one of claims 1 to 7, characterized in that the second forwarding device in the second site receives the first parameter set from the first forwarding device in the first site, including: The second forwarding device receives the first notification message from the first forwarding device, the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the first anycast label;

The second forwarding device receives a second parameter set from a third forwarding device in the first site, including: the second forwarding device receives a second notification message from the first forwarding device in the first site, the second notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the second anycast label.
The method according to claim 8, characterized in that the first notification message and the second notification message are IGP messages; or

The first advertisement message and the second advertisement message are BGP messages.
The method according to any one of claims 1 to 9, characterized in that the first forwarding device is a BFER, and the second forwarding device is a transit BFR; or,

The first forwarding device is transit BFR, and the second forwarding device is BFIR; or,

The first forwarding device and the second forwarding device are adjacent transit BFRs.
The method according to any one of claims 1 to 10, characterized in that, after the second forwarding device obtains the first correspondence based on the first parameter set and the BFR-ID of the third forwarding device, The method also includes:

The second forwarding device obtains a first BIER message. The first BIER message includes a first bit string, a label of the second forwarding device, and a multicast data message. The first bit string is identical to the first bit string. The BFR-ID of the first forwarding device corresponds to one or more of the BFR-IDs of the third forwarding device;

The second forwarding device obtains a second BIER message based on the first BIER message and the first corresponding relationship. The second BIER message includes a second bit string, the first anycast label and the first anycast label. In the multicast data message, the second bit string is obtained based on the F-BM in the first correspondence relationship between the first bit string and the first correspondence;

The second forwarding device sends the second BIER message.
The method according to claim 11, characterized in that the second forwarding device sends the second BIER message, including:

If the next hop matching the BFR prefix of the first forwarding device is in a fault state, the second forwarding device matches the BFR prefix of the third forwarding device in the second correspondence relationship. The next hop sends the second BIER message; or,

If the next hop matching the BFR prefix of the third forwarding device is in a fault state, the second forwarding device matches the BFR prefix of the first forwarding device in the first correspondence relationship. The next hop sends the second BIER message; or,

If the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device are not in a faulty state, the second forwarding device sends the second BIER to the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device, whichever has the smallest link cost. message; or,

If neither the next hop matching the BFR prefix of the first forwarding device nor the next hop matching the BFR prefix of the third forwarding device is in a fault state, the second forwarding device forwards the The one with the highest link network quality among the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device sends the second BIER message. text; or,

If neither the next hop matching the BFR prefix of the first forwarding device nor the next hop matching the BFR prefix of the third forwarding device is in a fault state, the second forwarding device forwards the Any one of the next hop matching the BFR prefix of the first forwarding device and the next hop matching the BFR prefix of the third forwarding device sends the second BIER message.
A parameter notification method, characterized by including:

The first forwarding device in the first site obtains a first parameter set, the first parameter set includes a first anycast label, the BFR-ID of the first forwarding device and the BFR prefix of the first forwarding device, the The first anycast tag is used to identify the first site;

The first forwarding device sends the first parameter set to a second forwarding device in the second site.
The method according to claim 13, characterized in that the first anycast label is a label or an IPv6 destination address.
The method according to claim 13 or 14, characterized in that the first parameter set further includes a bit string length BSL of the first forwarding device, a set identifier SI to which the first forwarding device belongs and the first One or more of the identifiers of the BIER subdomain where the forwarding device is located.
The method according to any one of claims 13 to 15, characterized in that the first forwarding device sends the first parameter set to the second forwarding device in the second site, including:

The first forwarding device sends a first notification message to the second forwarding device, where the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the first anycast label.
The method according to claim 16, characterized in that the first notification message is an IGP message or a BGP message.
The method according to any one of claims 13 to 17, characterized in that the first forwarding device is a BFER, and the second forwarding device is a transit BFR; or,

The first forwarding device is transit BFR, and the second forwarding device is BFIR; or,

The first forwarding device and the second forwarding device are adjacent transit BFRs.
The method according to any one of claims 13 to 18, characterized in that the method further includes:

The first forwarding device receives a third parameter set from a third forwarding device in the first site, where the third parameter set includes a first bypass label, the BFR-ID of the third forwarding device and the third The BFR prefix of the third forwarding device, the first bypass label is used to identify the third forwarding device;

The first forwarding device obtains a third correspondence based on the third parameter set, and the third correspondence includes the first bypass label, the F-BM matching the BFR-ID of the third forwarding device, and the next hop matching the BFR prefix of the third forwarding device.
The method according to claim 19, characterized in that after the first forwarding device sends the first parameter set to the second forwarding device in the second site, the method further includes:

The first forwarding device receives a first BIER message. The first BIER message includes a first bit string corresponding to the BFR-ID of the third forwarding device, the first anycast label and a multicast datagram. arts;

The first forwarding device obtains a second BIER message based on the first BIER message and the third corresponding relationship. The second BIER message includes a second bit string, the first bypass label and the Multicast data message, the second bit string is a bit string obtained based on the F-BM in the first bit string and the third corresponding relationship;

The first forwarding device sends the second BIER message to the third forwarding device.
The method according to any one of claims 13 to 20, characterized in that the method further includes:

The first forwarding device obtains a fourth parameter set. The fourth parameter set includes a second bypass tag, the BFR-ID of the first forwarding device, and the BFR prefix of the first forwarding device. The second bypass The label is used to identify the first forwarding device;

The first forwarding device sends the fourth parameter set to the third forwarding device.
A device for obtaining a correspondence relationship, which is characterized in that it is provided in the second forwarding device in the second site and includes:

A receiving unit, configured to receive a first parameter set from a first forwarding device in the first site, where the first parameter set includes a first broadcast standard tag, the BFR-ID of the first forwarding device and the BFR prefix of the first forwarding device, the first anycast tag is used to identify the first site;

The receiving unit is also configured to receive a second parameter set from a third forwarding device in the first site, where the second parameter set includes a second anycast tag, the BFR-ID of the third forwarding device, and The BFR prefix of the third forwarding device, the second anycast label is used to identify the first site;

A processing unit configured to obtain a first corresponding relationship based on the first parameter set and the BFR-ID of the third forwarding device, where the first corresponding relationship includes the BFR-ID of the first forwarding device and the The forwarding bit mask F-BM matched by the BFR-ID of the third forwarding device, the first anycast label and the next hop matching the BFR prefix of the first forwarding device;

The processing unit is further configured to obtain a second corresponding relationship based on the second parameter set and the BFR-ID of the first forwarding device, where the second corresponding relationship includes the BFR-ID of the first forwarding device. and the F-BM matching the BFR-ID of the third forwarding device, the second anycast label, and the next hop matching the BFR prefix of the third forwarding device.
The device according to claim 22, characterized in that the processing unit is used for:

Based on the first anycast tag and the second anycast tag, it is determined that the first forwarding device and the third forwarding device belong to the first site; based on the BFR-ID of the first forwarding device and The BFR-ID of the third forwarding device is used to obtain the F-BM; based on the F-BM, the first anycast tag and the BFR prefix of the first forwarding device, the first corresponding relationship is obtained , the first corresponding relationship includes the F-BM, the first anycast label, and the BFR prefix of the first forwarding device.
The device according to claim 22, characterized in that the processing unit is used for:

Based on the first anycast tag and the second anycast tag, it is determined that the first forwarding device and the third forwarding device belong to the first site; based on the BFR-ID of the first forwarding device and Obtain the F-BM based on the BFR-ID of the third forwarding device; determine the first outbound interface on the second forwarding device that reaches the first forwarding device based on the BFR prefix of the first forwarding device; The first correspondence relationship is obtained based on the F-BM, the first anycast label, the BFR prefix of the first forwarding device and the first outbound interface, and the first correspondence relationship includes the F -BM, the first anycast label, the BFR prefix of the first forwarding device, and the first outbound interface.
The device according to any one of claims 22 to 24, characterized in that the processing unit is used to:

Based on the first anycast tag and the second anycast tag, it is determined that the first forwarding device and the third forwarding device both belong to the first site; based on the BFR-ID of the first forwarding device and The BFR-ID of the third forwarding device is used to obtain the F-BM; based on the F-BM, the second anycast tag and the BFR prefix of the third forwarding device, the second corresponding relationship is obtained , the second corresponding relationship includes the F-BM, the second anycast label, and the BFR prefix of the third forwarding device.
The device according to any one of claims 22 to 24, characterized in that the processing unit is used for:

It is determined based on the first anycast tag and the second anycast tag that both the first forwarding device and the third forwarding device belong to the first site; based on the BFR-ID of the first forwarding device and Obtain the F-BM based on the BFR-ID of the third forwarding device; determine the second outbound interface on the second forwarding device that reaches the third forwarding device based on the BFR prefix of the third forwarding device; The second correspondence relationship is obtained based on the F-BM, the second anycast label, the BFR prefix of the third forwarding device and the second outbound interface, and the second correspondence relationship includes the F -BM, the second anycast label, the BFR prefix of the third forwarding device, and the second outbound interface.
The device according to any one of claims 22 to 25, wherein the first anycast tag and the second anycast tag are both tags; or

The first anycast label and the second anycast label are both IPv6 destination addresses.
The device according to any one of claims 22 to 27, wherein the first parameter set further includes a bit string length BSL of the first forwarding device, a set identifier SI to which the first forwarding device belongs. and one or more identifiers of the BIER subdomain where the first forwarding device is located;

The second parameter set also includes one or more of the bit string length BSL of the third forwarding device, the set identifier SI to which the third forwarding device belongs, and the identifier of the BIER subdomain in which the third forwarding device is located.
The device according to any one of claims 22 to 28, characterized in that the receiving unit is used for:

Receive a first notification message from the first forwarding device, the first notification message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the first anycast label; receive a message from the first site The second advertisement message of the first forwarding device, the The second advertisement message includes a BIER information sub-TLV, and the BIER information sub-TLV includes the second anycast label.
The device according to claim 29, wherein the first notification message and the second notification message are IGP messages; or

The first advertisement message and the second advertisement message are BGP messages.
The device according to any one of claims 22 to 30, wherein the first forwarding device is a BFER and the second forwarding device is a transit BFR; or,

The first forwarding device is transit BFR, and the second forwarding device is BFIR; or,

The first forwarding device and the second forwarding device are adjacent transit BFRs.
The device according to any one of claims 22 to 31, characterized in that the processing unit is also used for:

Obtain a first BIER message. The first BIER message includes a first bit string, a label of the second forwarding device, and a multicast data message. The first bit string is consistent with the BFR of the first forwarding device. - ID corresponds to one or more of the BFR-IDs of the third forwarding device; a second BIER message is obtained based on the first BIER message and the first correspondence, and the second BIER message Including a second bit string, the first anycast label and the multicast data message, the second bit string is obtained based on the F-BM in the first correspondence relationship between the first bit string and the first correspondence. ;

The device further includes: a sending unit, configured to send the second BIER message.
The device according to claim 32, characterized in that the sending unit is used for:

If the next hop matching the BFR prefix of the first forwarding device is in a fault state, sending the next hop matching the BFR prefix of the third forwarding device in the second correspondence relationship. the second BIER message; or

If the next hop matching the BFR prefix of the third forwarding device is in a fault state, sending the next hop matching the BFR prefix of the first forwarding device in the first correspondence relationship. the second BIER message; or

If neither the next hop that matches the BFR prefix of the first forwarding device nor the next hop that matches the BFR prefix of the third forwarding device is in a fault state, send the next hop to the first forwarding device. The second BIER message is sent by the one with the smallest link cost between the next hop that matches the BFR prefix of the forwarding device and the next hop that matches the BFR prefix of the third forwarding device; or

If neither the next hop that matches the BFR prefix of the first forwarding device nor the next hop that matches the BFR prefix of the third forwarding device is in a fault state, send the next hop to the first forwarding device. The next hop that matches the BFR prefix of the forwarding device and the next hop that matches the BFR prefix of the third forwarding device, whichever has the highest link network quality, sends the second BIER message; or

If neither the next hop that matches the BFR prefix of the first forwarding device nor the next hop that matches the BFR prefix of the third forwarding device is in a fault state, send the next hop to the first forwarding device. Any one of the next hop matching the BFR prefix of the forwarding device and the next hop matching the BFR prefix of the third forwarding device sends the second BIER message.
A parameter notification device, characterized in that it is installed on the first forwarding device in the first site and includes:

a processing unit, configured to obtain a first parameter set, the first parameter set comprising a first anycast label, a BFR-ID of the first forwarding device, and a BFR prefix of the first forwarding device, the first anycast label being used to identify the first site;

A sending unit, configured to send the first parameter set to a second forwarding device in the second site.
The device according to claim 34, wherein the first anycast label is a label or an IPv6 destination address.
The device according to claim 34 or 35 is characterized in that the first parameter set also includes one or more of the bit string length BSL of the first forwarding device, the set identifier SI to which the first forwarding device belongs, and the identifier of the BIER subdomain in which the first forwarding device is located.
The device according to any one of claims 34 to 36, characterized in that the sending unit is configured to send a first notification message to the second forwarding device, and the first notification message includes a BIER information sub- TLV, the BIER information sub-TLV includes the first anycast label.
The device according to claim 37, characterized in that the first notification message is an IGP message or a BGP message.
The device according to any one of claims 34 to 38, wherein the first forwarding device is a BFER and the second forwarding device is a transit BFR; or,

The first forwarding device is transit BFR, and the second forwarding device is BFIR; or,

The first forwarding device and the second forwarding device are adjacent transit BFRs.
The device according to any one of claims 34 to 39, characterized in that the device further includes:

A receiving unit configured to receive a third parameter set from a third forwarding device in the first site, where the third parameter set includes a first bypass label, the BFR-ID of the third forwarding device and the third BFR prefix of the forwarding device, the first bypass label is used to identify the third forwarding device;

The processing unit is further configured to obtain a third correspondence based on the third parameter set, where the third correspondence includes the first bypass tag and the F-BM matching the BFR-ID of the third forwarding device. and the next hop that matches the BFR prefix of the third forwarding device.
The device according to claim 40, characterized in that:

The receiving unit is also configured to receive a first BIER message, which includes a first bit string corresponding to the BFR-ID of the third forwarding device, the first anycast label, and multicast data. message;

The processing unit is further configured to obtain a second BIER message based on the first BIER message and the third corresponding relationship, where the second BIER message includes a second bit string, the first bypass tag and the In the multicast data message, the second bit string is a bit string obtained based on the F-BM in the first bit string and the third correspondence relationship;

The sending unit is also configured to send the second BIER message to the third forwarding device.
The device according to any one of claims 34 to 41, characterized in that:

The processing unit is also configured to obtain a fourth parameter set, the fourth parameter set includes a second bypass tag, the BFR-ID of the first forwarding device, and the BFR prefix of the first forwarding device, and the second The bypass label is used to identify the first forwarding device;

The sending unit is also configured to send the fourth parameter set to the third forwarding device.
A forwarding device, characterized in that the forwarding device includes a processor and a network interface, and the forwarding device executes any one of claims 1 to 12 by using the processor and the network interface. The method performed by the second forwarding device or the method performed by the first forwarding device according to any one of claims 13 to 21.
A computer-readable storage medium, characterized in that at least one instruction is stored in the storage medium, and when the instruction is executed on a computer, the computer executes the method according to any one of claims 1 to 21.
A computer program product, characterized in that the computer program product includes one or more computer program instructions, which when the computer program instructions are loaded and run by a computer, cause the computer to execute any one of claims 1-21 method described in the item.