CN114301839A

CN114301839A - Multicast message transmission method and device

Info

Publication number: CN114301839A
Application number: CN202011001070.0A
Authority: CN
Inventors: 王贵; 李良格; 谢经荣
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-09-22
Filing date: 2020-09-22
Publication date: 2022-04-08
Anticipated expiration: 2040-09-22
Also published as: CN114301839B

Abstract

The embodiment of the application discloses a multicast message transmission method and a device, wherein a first network device acquires a BIER message, the BIER message comprises a service identifier, and the service identifier comprises an SLA identifier used for indicating the SLA requirement which is required to be met by forwarding the BIER message. And the first network equipment determines a forwarding strategy according to the corresponding relation among the service identifier, the equipment identifier of the second network equipment and the forwarding strategy, wherein the forwarding strategy is used for indicating forwarding information meeting SLA requirements in the process of forwarding the BIER message to the second network equipment. And the first network equipment sends the BIER message to the second network equipment according to the forwarding strategy. Therefore, before forwarding the BIER message to the second network device, the first network device may determine a corresponding forwarding policy according to the service identifier and the device identifier of the second network device, and forward the BIER message to the second network device according to the forwarding policy, so as to meet the SLA requirement required to be met by forwarding the BIER message.

Description

Multicast message transmission method and device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a multicast message transmission method and apparatus.

Background

Bit-index based display replication (BIER) is a new multicast technology. Compared with the traditional multicast technology, the multicast technology encapsulates the destination node set of the multicast message at the message head in a bit string mode for sending, so that the intermediate node of the network does not need to establish a multicast tree for each multicast stream, and only needs to copy and forward according to the destination node set of the message head. In the BIER multicast technology, each destination node is an edge node in a multicast network, taking a network with less than 256 edge nodes as an example, each edge node is configured with a unique value of 1-256, namely an edge node Identifier (ID), a destination node set is represented by a Bit string (BitString) of 256 bits, and the position of each Bit in the Bit string represents an edge node. The edge node may be divided into a BIER forwarding entry router (BFIR) and a BIER Forwarding Exit Router (BFER), where a route located between the BFIR and the BFER and supporting BIER packet forwarding is a BIER Forwarding Router (BFR).

For convenience of understanding forwarding of the BIER packet, refer to a schematic structural diagram of a multicast network shown in fig. 1, where an ID in a BIER forwarding table (bit index forwarding table, BIFT) in fig. 1 is an edge node identifier. ID-1 refers to PE1, ID-2 refers to PE2, ID-3 refers to PE3, and ID-4 refers to PE 4. Forwarding BitMask (F-BM) indicates a BIER domain edge node set that can be reached through a neighbor when a packet is copied and sent to the next-hop neighbor. Neighbor (NBR), representing the next hop Neighbor node for a certain BFR-ID. When the PE4 node needs to send the multicast traffic to three nodes, PE1, PE2, and PE3, PE4 encapsulates the bit string BitString in the multicast packet as (0111). After receiving the multicast message, the P1 node searches its corresponding forwarding table, copies the message and modifies BitString as (0100 and 0011), forwards the multicast message with BitString as (0100) to PE3, and forwards the multicast message with BitString as (0011) to P2. After receiving the multicast message, the P2 searches its corresponding forwarding table, copies the message and modifies BitString to (0001 and 0010), forwards the multicast message with BitString of (0001) to the PE1, and forwards the multicast message with BitString of (0010) to the PE 2. Wherein, the Bit Positions (BP) in the BitString represent the edge routers.

However, in different application scenarios, different service requirements exist for forwarding the BIER packet, and how to meet the service requirement corresponding to BIER packet forwarding is a technical problem that needs to be solved urgently.

Disclosure of Invention

The embodiment of the application provides a multicast message transmission method and device, which can solve the problem of message forwarding of BIER messages between BFR and BFR-NBR so as to meet the service requirement.

In a first aspect of embodiments of the present application, a multicast message transmission method is provided, where the method may include: a first network device acquires a bit index to display and copy a BIER message, wherein the BIER message comprises a service identifier, the service identifier comprises a Service Level Agreement (SLA) identifier, and the SLA identifier is used for indicating SLA requirements required to be met by forwarding the BIER message; the first network device determines a forwarding policy corresponding to the service identifier and the device identifier of the second network device according to a corresponding relationship between the service identifier, the device identifier of the second network device and the forwarding policy, the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the forwarding policy corresponding relationship indicates a corresponding relationship between the service identifier and the device identifier of the second network device and the forwarding policy, and the forwarding policy indicates forwarding information meeting the SLA requirement in a process of forwarding the BIER packet to the second network device; and the first network equipment sends the BIER message to the second network equipment according to the forwarding strategy. In this embodiment, the second network device sends the first BGP routing information including the service identifier and the identifier of the first network segment to the first network device, so that the first network device can know that the first network segment is used to send the service traffic corresponding to the service identifier to the second network device, thereby meeting the SLA requirement required to be met for forwarding the BIER packet.

In a possible implementation manner, the service identifier is located in the BIER header. In this implementation, the service identifier may be a color identifier color in a BIER header or a differentiated services code DSCP, so as to indicate different SLA requirements through the color or DSCP.

In a possible implementation manner, the service identifier further includes a device identifier of the network device corresponding to the destination address in the BIER message. In this implementation manner, the service identifier may include not only an SLA identifier but also an equipment identifier, where the equipment identifier is an equipment identifier of a network equipment corresponding to a destination address in the BIER message, so as to distinguish different SLA requirements through the SLA identifier and the equipment identifier.

In a possible implementation manner, before the first network device sends the BIER packet to the second network device according to the forwarding policy, the method further includes: the first network equipment determines the equipment identification according to the forwarding strategy; and the first network equipment updates the service identifier in the BIER message by using the equipment of the second network equipment. In this implementation manner, when the service identifier includes the SLA identifier and the device identifier, since the device identifier is the device identifier of the network device corresponding to the destination address in the BIER message, and the destination address in the BIER message changes, that is, the service identifier also changes continuously, before the second network device sends the BIER message to the first network device, the device identifier needs to be determined according to the forwarding policy to update the service identifier, so that the first network device can identify the service identifier in the BIER message.

In a possible implementation manner, when a third network device exists between the first network device and the second network device on a forwarding path of the BIER packet, the sending, by the first network device, the BIER packet to the second network device according to the forwarding policy includes: the first network equipment determines the third network equipment according to the forwarding strategy, wherein the forwarding strategy indicates path information meeting the SLA requirement in the process of forwarding the BIER message to the second network equipment; and the first network equipment sends the BIER message to the second network equipment through the third network equipment. In this implementation manner, when a third network device exists between the first network device and the second network device, after the first network device determines the forwarding policy, the third network device may be determined according to the forwarding policy, so as to send the BIER packet to the second network device through the third network device. The third network device may be a network device that supports BIER forwarding or a network device that does not support BIER forwarding. When the third network device is a network device that does not support BIER forwarding, the first network device can sense the existence of the third network device through the forwarding policy, and then the BIER message is sent to the first network device through the third network device.

In a possible implementation manner, the sending, by the first network device, the BIER packet to the second network device by using the third network device includes: adding an extension field in the BIER message by the first network equipment, wherein the extension field comprises the equipment identifier of the second network equipment; and the first network equipment forwards the BIER message to the third network equipment, so that the third network equipment forwards the BIER message to the second network equipment according to the equipment identifier of the second network equipment. In this implementation manner, when the third network device is a network device that does not support BIER forwarding, in order to enable the third network device to forward the BIER message to the second network device after receiving the BIER message, the first network device may add an extension field to the BIER message when sending the BIER message to the third network device, where the extension field may include a device identifier of the second network device, so that the third network device may forward the BIER message to the second network device according to the device identifier in the extension field after receiving the BIER message.

In a possible implementation manner, the extension field further includes the service identifier. In this implementation, the extension field may include not only the device identifier of the second network device, but also a service identifier, for example, an SLA identifier in the service identifier.

In a possible implementation manner, when the BIER packet is a BIERv6 packet, the extension field is a segment routing extension header SRH field in the BIER packet. In this implementation, when the BIER message is the BIERv6 message, the extension field may be an SRH field in the BIER message.

In a possible implementation manner, when a third network device supports BIER forwarding, before the first network device determines, according to the correspondence between the service identifier and the device identifier of the second network device and the forwarding policy, the forwarding policy corresponding to the service identifier and the device identifier of the second network device, the method further includes: the first network equipment acquires a forwarding table entry, and updates a local forwarding table (BIFT) by using the forwarding table entry, wherein the forwarding table entry is used for indicating that the second network equipment is neighbor network equipment of the first network equipment; and the first network equipment determines second network equipment according to the BIFT. In this implementation manner, when the third network device is a BIER packet forwarding device, in a general case, the third network device is a neighbor network device of the first network device in the local forwarding table BIFT, and in order to meet the SLA requirement of BIER packet forwarding, the neighbor network device of the second network device may be designated as the first network device, and the first network device may update its own corresponding forwarding table BIFT, and then determine the second network device according to the updated BIFT.

In a possible implementation manner, the forwarding table entry is obtained by the first network device from a controller. In this implementation manner, considering that the capability of the first network device is limited, the first network device may update the local forwarding table bif in a manner that the controller issues an updated forwarding table entry.

In a second aspect of the embodiments of the present application, there is provided a multicast message transmission apparatus, including: an obtaining unit, configured to obtain a bit index to display and copy a BIER packet, where the BIER packet includes a service identifier, the service identifier includes a service level agreement SLA identifier, and the SLA identifier is used to indicate an SLA requirement that needs to be met by forwarding the BIER packet; a determining unit, configured to determine, according to a correspondence between the service identifier and a device identifier of a second network device and a forwarding policy, a forwarding policy corresponding to the service identifier and the device identifier of the second network device, where the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the correspondence between the forwarding policies indicates a correspondence between the service identifier and the device identifier of the second network device and the forwarding policy, and the forwarding policy indicates forwarding information meeting the SLA requirement in a process of forwarding the BIER packet to the second network device; and the sending unit is used for sending the BIER message to the second network equipment according to the forwarding strategy.

In a possible implementation manner, the service identifier is located in the BIER header.

In a possible implementation manner, the service identifier further includes a device identifier of the network device corresponding to the destination address in the BIER message.

In one possible implementation, the apparatus further includes: an update unit; the determining unit is further configured to determine the device identifier according to the forwarding policy before executing the sending unit; and the updating unit is used for updating the service identifier in the BIER message by using the device identifier of the second network device.

In a possible implementation manner, when a third network device exists between the apparatus and the second network device on the forwarding path of the BIER packet, the sending unit is specifically configured to determine the third network device according to the forwarding policy, where the forwarding policy indicates that path information meeting the SLA requirement is transmitted to the second network device in the process of forwarding the BIER packet; and sending the BIER message to the second network equipment through the third network equipment.

In a possible implementation manner, the sending unit is specifically configured to add an extension field in the BIER packet, where the extension field includes the device identifier of the second network device; and forwarding the BIER message to the third network equipment, so that the third network equipment forwards the BIER message to the second network equipment according to the equipment identifier of the second network equipment.

In a possible implementation manner, the extension field further includes the service identifier.

In a possible implementation manner, when the BIER packet is a BIERv6 packet, the extension field is a segment routing extension header SRH field in the BIER packet.

In a possible implementation manner, when the third network device supports BIER forwarding, the obtaining unit is further configured to obtain a forwarding table entry, update a local forwarding table BIFT by using the forwarding table entry, where the forwarding table entry is used to indicate that the second network device is a neighbor network device of the apparatus; the determining unit is further configured to determine a second network device according to the BIFT.

In one possible implementation, the forwarding entry is obtained by the apparatus from a controller.

In a third aspect of embodiments of the present application, there is provided a communication device, including: a processor and a memory; the memory for storing instructions or computer programs; the processor is configured to execute the instructions or the computer program in the memory to cause the communication device to perform the method of the first aspect.

In a fourth aspect of embodiments of the present application, there is provided a computer-readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform the method of the first aspect.

According to the technical scheme provided by the embodiment of the application, the first network equipment firstly acquires the bit index to display and copy the BIER message, the BIER message comprises the service identification, and the service identification comprises the SLA identification used for indicating the SLA requirement of the service level agreement SLA required to be met by forwarding the BIER message. The first network device may determine a forwarding policy corresponding to the service identifier and the device identifier of the second network device according to the correspondence between the service identifier, the device identifier of the second network device, and the forwarding policy. The second network device is a network device supporting BIER forwarding on a forwarding path of the BIER message, and the forwarding policy is used for indicating forwarding information meeting the SLA requirement in the process of forwarding the BIER message to the second network device. And the first network equipment sends the BIER message to the second network equipment according to the forwarding strategy. It can be seen that, with the multicast packet transmission method provided in this embodiment of the present application, before forwarding a BIER packet to a second network device, a first network device may determine a corresponding forwarding policy according to a service identifier and a device identifier of the second network device, and because forwarding information indicated by the forwarding policy may satisfy a corresponding SLA requirement in a process of forwarding the BIER packet, the first network device may forward the BIER packet to the second network device according to the forwarding policy, thereby satisfying an SLA requirement that needs to be satisfied for forwarding the BIER packet.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a diagram illustrating multicast message transmission;

fig. 2a is a schematic view of an application scenario provided in an embodiment of the present application;

fig. 2b is a schematic diagram of a forwarding policy structure provided in an embodiment of the present application;

fig. 2c is a schematic diagram of a forwarding table structure according to an embodiment of the present application;

fig. 3 is a flow chart of multicast message transmission according to an embodiment of the present application;

fig. 4a is a schematic structural diagram of a multicast message provided in the embodiment of the present application;

fig. 4b is a schematic diagram of another forwarding policy provided in the embodiment of the present application;

fig. 4c is a schematic diagram of another multicast packet structure provided in this embodiment;

fig. 5 is a flowchart of another multicast packet transmission provided in the embodiment of the present application;

fig. 6 is a flowchart of another multicast packet transmission provided in the embodiment of the present application;

fig. 7 is a schematic diagram of another forwarding table structure provided in the embodiment of the present application;

fig. 8 is a structural diagram of a multicast message transmission apparatus according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of another communication device according to an embodiment of the present application.

Detailed Description

In order to make those skilled in the art better understand the solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments.

Referring to the scene schematic diagram shown in fig. 2a, in the network system shown in fig. 2a, the network system includes 13 network devices, which are respectively a network device a, a network device B, a network device C, a network device Y, a network device Z, a network device E, a network device F, a network device I, a network device J, a network device K, a network device O, a network device P, and a network device Q. Network device a may be a BIER message forwarding ingress router (BFIR), whose corresponding BFR-ID is 1(0001), network device O, network device P, and network device Q are BIER message forwarding egress routers (BFERs), and their corresponding BFR-IDs are 2(0010), 3(0100), 4 (1000). For the network equipment between the BFIR and the BFER, part of the network equipment can be BFR supporting BIER message forwarding, and part of the network equipment can not support the network equipment supporting BIER message forwarding. For example, network device Y and network device Z do not support BIER packet forwarding. In some scenarios, a network device may also be referred to as a node, and refers to a device providing a route forwarding function in a network system, and for example, may be a router, a switch, a repeater, or a Label Switching Router (LSR).

In one case, different service requirements exist for forwarding the BIER packet, and the BFR needs to forward the BIER packet while meeting the service requirements when forwarding the BIER packet to the BFR-NBR.

In another case, multiple paths may exist between the BFRs and the BFR-NBR, taking the network structure shown in fig. 2a as an example, two paths exist from network device B to network device C, and in order to plan a forwarding path of a BIER packet, in a bit-index-based copy-on-display traffic engineering (BIER-TE), a corresponding identifier is generally allocated to each BFR, for example, a corresponding identifier is allocated to both network device Y and network device Z, and the passing BFR identifier on the forwarding path is added to BitString, so that when the BFR receives the BIER packet, a specific forwarding path may be determined according to the BitString in the BIER packet. When a large number of adjacency relations exist in the BIER-TE network topology, the BitString is too long, and the packet load rate and the forwarding efficiency are affected.

In another case, when a network device which does not support BIER packet forwarding exists between the BFR and the BFR-NBR, the BFR cannot identify the network device which does not support BIER packet forwarding through the forwarding table BIFT when forwarding the BIER packet to the BFR-NBR, resulting in that strict path control cannot be implemented. For example, network device Y in fig. 2a does not support BIER packet forwarding, and when the forwarding path of the BIER packet is planned to be B-Y-C, because the information of network device Y does not exist in the forwarding table entry of network device B, network device B cannot forward the BIER packet according to the forwarding path.

Based on the above problem, an embodiment of the present application provides a multicast message transmission method, and the method meets an SAL requirement corresponding to BIER message forwarding by a way of pre-configuring a forwarding policy. After receiving the BIER message, the first network device may determine a corresponding forwarding policy according to the service identifier, the device identifier of the second network device, and the forwarding policy correspondence. The first network device can forward the BIER message to the second network device according to the forwarding policy, thereby satisfying the SAL requirement corresponding to the BIER message. In addition, when the first network device corresponds to multiple neighbor network devices, the next-hop neighbor network device can be determined through a pre-obtained forwarding strategy, and the identifier of the next-hop network device does not need to be carried in a bit string in the BIER message, so that the load of the BIER message is reduced, and the message forwarding efficiency is improved.

The forwarding policy may BE a forwarding mode that meets an SAL requirement corresponding to the forwarding BIER packet, where the forwarding mode may include GBW-EF bandwidth-guaranteed fast forwarding (GBW-EF), bandwidth-guaranteed forwarding (GBW-AF), normal fast forwarding (DS-EF), normal guaranteed forwarding (DS-AF), best-effort forwarding (best-effort, BE), and the like. Or, the forwarding policy may also be a forwarding path that meets the SAL requirement corresponding to the forwarding BIER packet. In this case, the controller may collect the topology of the current network system through a border gateway link-state protocol (BGP-LS), and calculate a route according to a service-level aggregation (SLA). And simultaneously, issuing a forwarding strategy policy to the nodes which need to specify the forwarding path and can meet the SLA requirement. As shown in fig. 2B, the controller issues two forwarding policies policy to the node B to specify different paths for BIER messages requiring different SLAs to the node C. And simultaneously, issuing three forwarding strategies to the C node to specify forwarding paths corresponding to different BFERs. Specifically, the controller may only issue the forwarding policy for the node having the divergent path, or may issue the forwarding policy for all BFRs on the multicast forwarding path, so as to implement strict path control, and the specific implementation of the routing policy issued by the controller is not limited herein. For example, through the forwarding policy, the network device B may determine that a forwarding path corresponding to forwarding the BIER packet to the network device C is Y-C.

It should be noted that the first network device and the second network device related in the implementation of the present application may be any two network devices supporting BIER message forwarding in a network transmission system. Specifically, the first network device and the second network device may be mutually neighboring network devices. For example, in the network structure shown in fig. 2a, the first network device is network device a, and the second network device is network device B. Or, the first network device is network device B, the second network device is network device C, where network device Y and network device Z both do not support BIER packet forwarding, and network device B and network device C are still neighbor network devices. Or, the network device a, the network device B, and the network device C all support BIER packet forwarding, but in a designated manner, the network device C is a neighbor network device of the network device a, and at this time, the first network device may be the network device a, and the second network device may be the network device C. The BIER message in the embodiment of the present application may be a multicast message in an IPv4 network, or may also be a multicast message in an IPv6 network.

For convenience of understanding, the following description will be made with reference to the network system structure shown in fig. 2a as an example, and refer to fig. 3, which is a flowchart of a multicast message transmission method provided in an embodiment of the present application, and as shown in fig. 3, the method may include:

s301: the first network equipment acquires a BIER message, wherein the BIER message comprises a service identifier.

In this embodiment, a first network device first obtains a BIER packet, where the BIER packet includes a service identifier, and the service identifier includes a Service Level Agreement (SLA) identifier, where the SLA identifier is used to indicate an SLA requirement that needs to be met for forwarding the BIER packet, and different SLA identifiers correspond to different SLA requirements, where the SLA requirements may be bandwidth, delay, jitter rate, and the like.

Specifically, the service identifier may be determined according to a service type to which the BIER packet belongs, where different service types correspond to different service identifiers, and different service identifiers correspond to different SLA requirements. The service type may include video, audio, text, etc. The service identifier is a first identifier, the first identifier may identify a color, and the color identifier is used to represent a specific SAL requirement. The color identifier color may be encapsulated in the header of the BIER message. Or, the first identifier may be a Differentiated Services Code Point (DSCP), and the DSCP may guarantee quality of service (QoS) of communication, and encode 8 identifier bytes at the IP header of the BIER packet to divide the service class. Or, the service identifier may also be a second identifier, where the second identifier may include an SAL identifier and an equipment identifier, and the equipment identifier is an equipment identifier of the network equipment corresponding to the destination address in the BIER message. The implementation of the specific representation form of the service identifier will be described in the following embodiments.

S302: and the first network equipment determines a forwarding strategy corresponding to the service identifier and the equipment identifier of the second network equipment according to the corresponding relation of the service identifier, the equipment identifier of the second network equipment and the forwarding strategy.

In this embodiment, after acquiring the BIER packet, the first network device may obtain the service identifier by analyzing the BIER packet, and determine the matching forwarding policy according to the correspondence between the service identifier, the device identifier of the second network device, and the forwarding policy. The second network device is a network device supporting BIER forwarding on a BIER message forwarding path, the forwarding policy corresponding relationship refers to a corresponding relationship between the service identifier, the device identifier of the second network device, and a forwarding policy, and the forwarding policy is used for indicating forwarding information meeting SLA requirements in the process of forwarding the BIER message to the second network device.

Specifically, the controller may issue a corresponding relationship between the service identifier, the device identifier of the second network device, and the forwarding policy when issuing the forwarding policy to the first network device, and may determine the forwarding policy according to the corresponding relationship between the service identifier, the device identifier of the second network device, and the forwarding policy when the first network device obtains the service identifier and the device identifier of the second network device. For example, as shown in fig. 2B, the first network device is network device B, and determines a forwarding policy1 according to the service identifier, the device identifier of the second network device (e.g., network device C), and the forwarding policy corresponding relationship, so that when the policy1 indicates that the BIER packet is forwarded to network device C, the BIER packet passes through network device Y. When the first network device is network device C and determines forwarding policy2 according to the service identifier, the device identifier of the second network device (e.g., network device O), and the forwarding policy corresponding relationship, policy2 indicates that the BIER packet is forwarded to network device O, and the BIER packet passes through network device E and network device I.

In a specific implementation manner, before the first network device determines the forwarding policy according to the service identifier, the device identifier of the second network device, and the forwarding policy corresponding relationship, the first network device needs to determine the second network device. Specifically, the first network device determines the second network device according to the bit string Bitstring in the BIER message and the forwarding table BIFT. The bit string BitString may only include device identifiers of BIER packet forwarding egress network devices (e.g., device identifiers of network device O, network device P, and network device Q). In one scenario, the forwarding table BIFT may be a forwarding table pre-stored locally by the first network device, where the forwarding table is used to indicate a neighbor network device adjacent to the first network device and supporting BIER message forwarding. For example, the first network device is network device a, and its corresponding neighbor network device is network device B.

In another case, the forwarding table BIFT may also be a forwarding table obtained by updating, by the first network device, the local forwarding table BIFT according to a forwarding table entry issued by the controller, where the forwarding table is used to designate the second network device as a neighbor network device of the first network device. Specifically, the controller may designate a neighbor network device according to the SLA and the network topology corresponding to the BIER packet, and issue a forwarding table including the designated neighbor network device to the first network device. The first network device updates the local forwarding table BIFT according to the forwarding table entry, and further determines the second network device according to the bit string and the updated BIFT. Referring to the application scenario diagram shown in fig. 2C, the first network device is network device a, both network device B and network device C support BIER packet forwarding, and if the neighbor network device of network device a is designated as network device C in the forwarding table updated on network device a, the second network device is network device C.

S303: and the first network equipment sends the BIER message to the second network equipment according to the forwarding strategy.

In this embodiment, when the first network device determines the forwarding policy, the BIER packet may be sent to the second network device according to the forwarding information indicated by the forwarding policy, so as to meet the service level agreement SLA requirement that needs to be met for forwarding the BIER packet.

In one case, when the forwarding policy is a forwarding mode that meets the SLA requirement corresponding to BIER message forwarding, the first network device sends the BIER message to the second network device according to the forwarding mode. For example, if the forwarding policy is to ensure fast forwarding of GBW-EF of bandwidth, the first network device forwards the BIER packet to the second network device according to the GBW-EF forwarding mode. In another case, when a third network device exists between the first network device and the second network device, the forwarding policy may be a forwarding path that satisfies a SLA requirement for BIER packet forwarding. The first network device determines a third network device according to the forwarding policy, and the first network device sends the BIER message to the second network device through the third network device. As shown in fig. 2C, if the first network device is network device a, the second network device is network device C, the determined forwarding policy1 is determined, and the third network device determined by policy1 is network device B and network device Z. Or, the third network device may also be a network device that does not support BIER forwarding, and since the third network device does not support BIER forwarding, the first network device cannot identify the third network device, and the forwarding policy may indicate the third network device at this time. As shown in fig. 2B, if the network device Y is a network device that does not support BIER forwarding, the first network device is a network device B, the second network device is a network device C, and the determined forwarding policy is policy1, it can be determined through policy1 that the network device B will forward the BIER packet to the network device C through the network device Y.

Before the first network device sends the BIER packet to the second network device, different operations may be performed according to actual application conditions, and specifically, the operations may be:

in one case, when the service identifier is a first identifier, such as a color identifier color, the first identifier can be used globally in the network system without updating the first identifier. The first network device may modify only a Destination Address (DA) in the BIER message to an address of the second network device. Taking the BIERv6 message as an example, for example, as shown in fig. 4a, if the first network device is network device a and the second network device is network device B, when the network device a forwards the BIER message to the network device B, the network device a modifies the IPv6 destination address DA into the address of the network device B. And when a third network device exists between the first network device and the second network device, the first network device modifies the destination address DA in the BIER message into the address of the third network device. For example, as shown in fig. 4a, if the first network device is network device B, the second network device is network device C, and the third network device is network device Y, network device B modifies IPv6 destination address DA in the BIER message to the address of network device Y. And when the network equipment Y receives the BIER message, modifying the IPv6 destination address DA in the BIER message into the address of the network equipment C, and forwarding the address to the network equipment C.

Further, when the third network device is a network device that does not support BIER forwarding, in order to enable the third network device to forward the BIER packet to the second network device after receiving the BIER packet sent by the first network device, the first network device may further add an extension field to the BIER packet before forwarding the BIER packet to the third network device, where the extension field may include a device identifier of the second network device, so that the third network device forwards the BIER packet to the second network device through the device identifier of the second network device after receiving the BIER packet. Taking the BIEv6 message as an example, as shown in fig. 4a, when the network device B forwards the BIER message to the network device Y, the extension field is a segment routing extension header (SRH) field of the BIER message, and the device identifier of the network device C is added to the SRH field. After receiving the BIER message, network device Y determines network device C according to the device identifier in SRH, and forwards the BIER message to network device C. Specifically, after the third network device determines the second network device according to the device identifier of the second network device, the device identifier in the BIER message may be deleted, and then the BIER message is forwarded to the second network device. For example, in fig. 4a, network device Y deletes SRH and forwards the BIER message to network device C. Taking the BIERv4 message as an example, specifically, in a multi-protocol label switching (MPLS) network, the extension field may be a label in the BIER message, and the label carries the device identifier of the second network device. The device identifier of the second network device may be a Router identifier (Router-ID), and the Router-ID may be an Internet Protocol (IP) address or a loopback address of the network device.

Another situation is that when the service identifier includes an SLA identifier and a device identifier, where the device identifier is an identifier of a network device corresponding to a destination address in the BIER message. Therefore, when the first network device forwards the BIER message to the second network device, it needs to acquire the identifier of the second network device corresponding to the forwarded BIER message, and further needs to update the service identifier. In a specific implementation, the first network device may determine the device identifier of the second network device according to a forwarding policy, where the forwarding policy includes the device identifier of the second network device. For example, as shown in fig. 4B and 4C, the first network device is network device B, the second network device is network device C, and service identifier B::1 in the BIER message received by network device B and sent by network device a, where B is device identifier of network device B and 1 is SLA identifier. When the forwarding policy determined by the network device according to the service identifier and the device identifier of the network device C is policy1, the service identifier C::1 can be known through the policy 1. The network device B modifies the service identification B::1 in the BIER message into C::1, and then sends the BIER message to the network device C. The service identifier in the BIER message acquired by the first network device includes a device identifier and an SLA identifier of the first network device, where the device identifier of the first network device may be determined by the previous-hop network device according to an SLA requirement corresponding to the BIER message, or acquired by the previous-hop network device from a controller.

In this case, the first network device also needs to modify the destination address of the BIER packet to the address of the second network device. And when a third network device exists between the first network device and the second network device, the first network device modifies the destination address DA in the BIER message into the address of the third network device. Taking the BIERv6 message as an example, as shown in fig. 4C, if the first network device is network device B, the second network device is network device C, and the third network device is network device Y, network device B modifies the IPv6 destination address DA in the BIER message to the address of network device Y. And when the network equipment Y receives the BIER message, modifying the IPv6 destination address DA in the BIER message into the address of the network equipment C, and forwarding the address to the network equipment C. Further, when the third network device is a network device that does not support BIER forwarding, in order to enable the third network device to forward the BIER message to the second network device after receiving the BIER message sent by the first network device, the first network device may further add a device identifier of the second network device in the BIER message before forwarding the BIER message to the third network device, so that the third network device forwards the BIER message to the second network device through the device identifier of the second network device after receiving the BIER message. In this case, the first network device adds the device identifier of the second network device to the SRH of the BIER message, for example, as shown in fig. 4 c.

In order to embody the continuity of message transmission, in the embodiment of the present application, a BIER message sent by a first network device to a third network device and a BIER message sent by the third network device to a second network device are both referred to as BIER messages, but it can be understood that there is a difference between a BIER message sent by the first network device to the third network device and a BIER message sent by the third network device to the second network device in an actual application scenario. For example, the Time To Live (TTL) information and the next hop node information may be different, that is, when the third network device forwards the BIER packet sent by the first network device to the second network device, the BIER packet may be an updated BIER packet with some necessary information modified. The BIER message sent by the first network device and the updated BIER message sent by the third network device may carry the same information such as a load (payload) and a service identifier.

For the sake of understanding, the following description will be made with reference to the network structure shown in fig. 2a to describe a corresponding specific implementation of the embodiment of the present application. Referring to fig. 5, which is a flowchart of another multicast packet transmission method provided in this embodiment of the present application, as shown in fig. 5, the method takes a service identifier as a first identifier, for example, a color identifier as an example, and may include:

s501: the network equipment A acquires the BIER message.

In this embodiment, when the BIER message acquired by the network device a does not include the service identifier, for example, when the network device a receives the BIER message sent by the user equipment or generates the BIER message by itself, the corresponding color identifier color may be determined according to the SLA requirement corresponding to the BIER message, and then the color identifier color is added to the BIER message.

S502: and the network equipment A sends the BIER message to the network equipment B.

After the network device a adds the color identification color message to the BIER message, it can determine the neighbor network device, i.e. the network device B, according to the bit string in the BIER message and the forwarding table BIFT. Meanwhile, the destination address in the BIER message is modified into the address of the network equipment B, and the BIER message is forwarded to the network equipment B. For example, as shown in fig. 4a, taking BIERv6 message as an example, the IPv6 destination address DA is modified to the address of network device B.

S503: and the network equipment B determines the network equipment C according to the BIER message and the forwarding table BIFT.

After receiving the BIER packet sent by network device a, network device B may determine, according to the forwarding table BIFT, a network device whose next hop supports BIER packet forwarding, that is, network device C.

When network device Y and network device Z are network devices that do not support BIER message forwarding, network device B may determine network device C directly according to the bit string in the BIER message and the local forwarding table BIFT. When the network device Y and/or the network device Z are network devices supporting BIER message forwarding, the next-hop neighbor network device recorded by the local forwarding table BIFT is usually the network device Y or the network device Z, and in order to make the neighbor network device corresponding to the network device B be the network device C, the network device Y and/or the network device Z may be implemented by updating the forwarding table BIFT. For the specific implementation of the network device B determining the network device C according to the forwarding table, reference may be made to the description of the first network device determining the second network device in S302.

S504: and the network equipment B determines a corresponding forwarding strategy according to the equipment identifier and the color identifier color of the network equipment C.

In this embodiment, the controller may issue a forwarding policy to the network device B, and issue a corresponding relationship between the forwarding policy and the device identifier and the color identifier color. And when the network equipment B determines the network equipment C, determining a forwarding strategy according to the equipment identifier, the color identifier and the corresponding relation of the network equipment C. See the relevant description of S302 for network device B determining the implementation of the forwarding policy according to the device identifier and the color identifier of network device C.

S505: and the network equipment B determines the network equipment Y according to the forwarding strategy and forwards the BIER message to the network equipment Y.

After the network device B determines the forwarding policy, it may determine the next-hop network device, that is, the network device Y, according to the forwarding policy, so as to forward the BIER packet to the network device Y. When the network device B forwards the BIER message to the network device Y, the destination address in the BIER message is modified into the address of the network device Y. As in fig. 4a, the IPv6 destination address is modified to the address of network device Y.

In a specific implementation manner, when the network device Y does not support BIER packet forwarding, since there is no corresponding forwarding table BIFT, it cannot determine the next-hop network device according to the forwarding table BIFT after receiving the BIER packet. In order to enable the network device Y to perform normal forwarding, when the network device B forwards the BIER packet to the network device Y, the device identifier of the network device C is added to the BIER packet, so that the network device Y can perform subsequent forwarding according to the device identifier of the network device C. Specifically, network device B may add the device identifier of network device C to the SRH in the BIER message. As shown in fig. 4a, the SRH of the BIER message carries the address of network device C. For a specific implementation of adding the device identifier to the network device B, reference may be made to the relevant description of S303.

S506: and the network equipment Y forwards the BIER message to the network equipment C according to the equipment identifier of the network equipment C in the BIER message.

When network device Y receives the BIER message forwarded by network device B, it may determine the next-hop network device, i.e., network device C, according to the device identifier carried by SRH in the BIER message, and further forward the BIER message to the next network device. Specifically, when forwarding the BIER packet to the network device C, the network device Y may delete the device identifier of the network device C in the SRH, and modify the destination address in the BIER packet to the address of the network device C. As shown in fig. 4 a.

S507: and the network equipment C determines the network equipment P and the network equipment O according to the BIER message and the forwarding table BIFT, and copies the BIER message.

In this embodiment, when the network device determines that there are multiple egress network devices, the BIER packet is copied to forward the BIER packet to each egress network device. For the specific implementation of determining the network device P and the network device O by the network device C according to the forwarding table BIFT, see S503.

S508: and the network equipment C determines a corresponding first forwarding strategy according to the equipment identifier of the network equipment P and the color identifier color in the BIER message.

S509: and the network equipment C determines a corresponding second forwarding strategy according to the equipment identifier of the network equipment O and the color device identifier color in the BIER message.

In this embodiment, the controller may issue a forwarding policy to the network device C, so that the network device C may determine a specific forwarding policy according to the device identifier of the network device P and the color identifier color. As shown in fig. 2b, the network device C matches to the forwarding policy1 according to the device identifier and the color identifier color of the network device P; and matching the device identifier and the color identifier of the network device O to a forwarding policy 2. The specific implementation of the network device C determining the forwarding policy according to the device identifier and the color identifier color may be referred to as S504.

S510: and the network equipment C determines the network equipment E according to the first forwarding strategy and sends a first BIER message to the network equipment E.

S511: and the network equipment C determines the network equipment E according to the second forwarding strategy and sends a second BIER message to the network equipment E.

For example, as shown in fig. 4a, network device C sends two BIER messages to network device E, where the IPv6 destination addresses in the two BIER messages are both addresses of network device E, but the device identifiers of the network devices carried by SRH are different. Wherein, the equipment identification carried by the SRH is related to the determined forwarding strategy. For example, as shown in fig. 2b, a first BIER packet sent to network device P corresponds to a first forwarding policy1, a path corresponding to policy1 is E, J and P, and an SRH of the first BIER packet includes device identifiers of network device P and network device J; the second BIER packet sent to network device O corresponds to the second forwarding policy2, the paths corresponding to policy2 are E, I and O, and the SRH of the second BIER packet includes the device identifier of network device O and network device I. See S505 for determining, by the network device C, a specific implementation of the network device E according to the first forwarding policy or the second forwarding policy.

S512: and the network equipment E forwards the first BIER message to the network equipment J according to the equipment identifier in the first BIER message, and forwards the second BIER message to the network equipment I according to the equipment identifier in the second BIER message.

S513: and the network equipment J forwards the BIER message to the network equipment P according to the equipment identifier in the first BIER message.

S514: and the network equipment I forwards the BIER message to the network equipment O according to the equipment identifier in the second BIER message.

See S506 for specific implementations of S512, S513, and S514, among others.

Referring to fig. 6, which is a flowchart of another multicast packet transmission method provided in this embodiment of the present application, as shown in fig. 6, in this embodiment, a service identifier is described as an example, and specifically, with reference to fig. 4b as an example, the method may include:

s601: the network equipment A acquires the BIER message and determines a forwarding strategy according to the BIER message.

In this embodiment, when the network device a receives a BIER message sent by a previous hop network device (e.g., user equipment) or generates a BIER message by itself, the network device a may determine a corresponding forwarding policy according to an SLA requirement corresponding to an SLA identifier included in a service identifier in the BIER message. The forwarding policy may be used to indicate a device identifier of the network device corresponding to the BIER packet, where the device identifier may satisfy the quality of service required for forwarding the BIER packet. Specifically, the controller may issue a forwarding policy to the network device a and a corresponding relationship between the forwarding policy and the SLA, and when the network device a determines the SLA corresponding to the BIER packet, the forwarding policy may be determined according to the SLA and the corresponding relationship. As shown in fig. 4b, a forwarding policy1 and a forwarding policy2 are issued at network device a.

S602: and the network equipment A updates the service identifier according to the forwarding strategy.

After the network device a determines the forwarding policy, the updated service identifier may be determined according to the forwarding policy. As shown in FIG. 4B, when network device A determines the forwarding policy1, then the policy1 specifies the traffic identification B:: 1. Wherein, B::1 and B::2 both point to the network device B, and 1 and 2 respectively represent different SLA identifiers.

S603: and the network equipment A sends the BIER message to the network equipment B according to the forwarding strategy.

In this embodiment, after the network device a determines the updated service identifier, the network device a may update the service identifier in the BIER message by using the updated request identifier, modify the destination address in the BIER message into the address of the network device B, and then send the BIER message to the network device B. As shown in fig. 4c, the IPv6 destination address in the BIER message is modified to be the device of network device B.

S604: and the network equipment B determines the network equipment C according to the BIER message and the forwarding table BIFT.

For specific implementation of S604, reference may be made to the detailed description of S503, which is not described herein again.

S605: and the network equipment B determines a corresponding forwarding strategy according to the equipment identifier and the service identifier of the network equipment C.

In this embodiment, the network device B may obtain the forwarding policy and the corresponding relationship between the device identifier, the service identifier and the forwarding policy from the controller, and when the network device B determines the network device C, the network device B may determine the corresponding forwarding policy according to the device identifier of the network device C and the service identifier in the BIER message. As shown in FIG. 4B, the network device B determines a corresponding forwarding policy1 according to the device ID of the network device C and the service ID B:: 1.

S606; and the network equipment B updates the service identifier according to the forwarding strategy, determines the network equipment Y and forwards the BIER message to the network equipment Y.

After the network device B determines the forwarding policy, the service identifier and the next hop network device Y may be updated according to the forwarding policy, so as to forward the BIER packet to the network device Y. As shown in FIG. 4b, the service identifier corresponding to policy1 is C::1, and the next hop network device is Y; the service identifier corresponding to policy2 is C::2, and the next hop network device is Z. The following one-hop network device in this embodiment is described as Y.

In a specific embodiment, after the network device B determines the device identifier of the network device C, in order to enable the network device Y to know that the BIER packet is forwarded to the network device C through the device identifier, before the BIER packet is forwarded to the network device Y, an extension field is added to the BIER packet, where the extension field includes the device identifier of the network device C. Meanwhile, the network device B modifies the destination address in the BIER message into the address of the network device Y. As shown in fig. 4c, the format of the BIER message sent by network device B to network device Y. For the implementation that network device B forwards the BIER packet to network device Y, see S505.

S607: and the network equipment Y forwards the BIER message to the network equipment C according to the extension field in the BIER.

After receiving the BIER message forwarded by network device B, network device Y may determine the next-hop network device, that is, network device C, according to the extended field in the BIER message, and forward the BIER message to network device C. Specifically, when forwarding the BIER packet to the network device C, the network device Y may delete the device identifier of the network device C in the extension field, and modify the destination address in the BIER packet to the address of the network device C. For example, the format of the BIER message sent by network device Y to network device C in fig. 4C.

S608: and the network equipment C determines the network equipment P and the network equipment O according to the BIER message and the forwarding table BIFT, and copies the BIER message.

For specific implementation of S608, refer to S507, and this embodiment is not described herein again.

S609: and the network equipment C determines a first forwarding strategy according to the equipment identifier of the network equipment P and the service identifier in the BIER message.

S610: and the network equipment C determines a second forwarding strategy according to the equipment identifier of the network equipment O and the service identifier in the BIER message.

In this embodiment, the network device C may obtain multiple forwarding policies from the controller, and obtain a correspondence between the device identifier, the service identifier, and the forwarding policy. After receiving the BIER message, the network equipment C can determine a first forwarding strategy according to the equipment identifier of the network equipment P and the service identifier C::1 in the BIER message and the corresponding relation; and determining a second forwarding strategy according to the equipment identifier of the network equipment O, the service identifier C::1 in the BIER message and the corresponding relation. For example, as shown in FIG. 4b, the network device C matches to the forwarding policy1 according to the device identifications P and C::1 of the network device P, and matches to the forwarding policy2 according to the device identifications O and C::1 of the network device O. For specific implementation of S609 and S610, see S509.

S611: and the network equipment C determines the network equipment E according to the first forwarding strategy and sends a first BIER message to the network equipment E.

S612: and the network equipment C determines the network equipment E according to the second forwarding strategy and sends a second BIER message to the network equipment E.

For example, as shown in fig. 4C, the network device C sends two BIER messages to the network device E, and the IPv6 destination addresses in the two BIER messages are both addresses of the network device E, but the device identifiers of the network devices carried by the SRH are different. Wherein, the equipment identification carried by the SRH is related to the determined forwarding strategy. For example, a first BIER packet sent to network device P corresponds to a first forwarding policy1, where paths corresponding to policy1 are E, J and P, and an SRH of the first BIER packet includes device identifiers of network device P and network device J; the second BIER packet sent to network device O corresponds to the second forwarding policy2, the paths corresponding to policy2 are E, I and O, and the SRH of the second BIER packet includes network device O and network device I.

For determining the specific implementation of the network device E according to the first forwarding policy or the second forwarding policy, see S505, S510, or S511 for the network device C.

S613: and the network equipment E forwards the first BIER message to the network equipment J according to the equipment identifier in the first BIER message, and forwards the second BIER message to the network equipment I according to the equipment identifier in the second BIER message.

S614: and the network equipment J forwards the first BIER message to the network equipment P according to the equipment identifier in the first BIER message.

S615: and the network equipment I forwards the second BIER message to the network equipment O according to the equipment identifier in the second BIER message.

For specific implementation of S613-S615, reference may be made to the related description of S607.

In addition, in order to solve the problem that a plurality of paths exist between the BFR and the BFR-NBR or network equipment which does not support BIER message forwarding exists between the BFR and the BFR-NBR, and thus the BIER message cannot be effectively forwarded, another solution is provided in the embodiments of the present application, specifically, specified forwarding path information is newly added to the forwarding table BIFT, and after receiving the BIER message, the first network equipment can obtain a specific forwarding path by searching the forwarding table BIFT, and then forward the BIER message according to the forwarding path. The specific implementation can include: the first network equipment acquires the BIER message and determines a forwarding path according to the bit string of the BIER, the equipment identifier of the second network equipment and the forwarding table; and the first network equipment sends the BIER message to the second network equipment according to the forwarding path. For example, as shown in fig. 7, the controller may determine a specific path according to the SLA and the network topology, and send the path information to the network device a, so that the network device a adds the path information to the forwarding table. After the network device a acquires the BIER message, it may determine that the forwarding path is B-Y-C according to the bit string (0110) in the BIER message and the device identifier C of the second network device. And the network equipment A sends a BIER message to the network equipment C according to the forwarding path B-Y-C.

In a specific embodiment, before determining a forwarding path according to the bit string of the BIER packet, the device identifier of the second network device, and the forwarding table, the first network device needs to determine the second network device. See the relevant description of S302 for a specific implementation of the first network device determining the second network device. For a specific implementation that the first network device sends the BIER packet to the second network device, reference may be made to the relevant description of S303.

Based on the above method embodiments, the present application embodiment further provides a multicast packet transmission apparatus, which will be described below with reference to the accompanying drawings.

Referring to fig. 8, which is a block diagram of a multicast message transmission apparatus provided in this embodiment of the present application, the apparatus 800 may be applied to a first network device, and perform the functions of the first network device in the embodiment shown in fig. 3, where the apparatus 800 may include: an acquisition unit 801, a determination unit 802, and a transmission unit 803.

An obtaining unit 801, configured to obtain a bit index to display a duplicate BIER packet, where the BIER packet includes a service identifier, the service identifier includes a service level agreement SLA identifier, and the SLA identifier is used to indicate an SLA requirement that needs to be met for forwarding the BIER packet.

The specific implementation of the obtaining unit 801 may refer to the detailed description of S301 in the embodiment described in fig. 3.

A determining unit 802, configured to determine, according to a correspondence between the service identifier, a device identifier of a second network device, and a forwarding policy, a forwarding policy corresponding to the service identifier and the device identifier of the second network device, where the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the forwarding policy correspondence indicates a correspondence between the service identifier and the device identifier of the second network device, and the forwarding policy indicates forwarding information meeting the SLA requirement in a process of forwarding the BIER packet to the second network device.

The specific implementation of the determining unit 802 may refer to the detailed description of S302 in the embodiment described in fig. 3.

A sending unit 803, configured to send the BIER packet to the second network device according to the forwarding policy.

The specific implementation of the sending unit 803 may refer to the embodiment described in fig. 3 to find a detailed description of S303.

In a possible implementation manner, the service identifier is located in the BIER header. The encapsulation format of the service identifier in the BIER message can be seen in the detailed description of S301.

In a possible implementation manner, the service identifier further includes a device identifier of the network device corresponding to the destination address in the BIER message. The encapsulation format of the service identifier in the BIER message can be seen in the detailed description of S301.

In one possible implementation, the apparatus further includes: updating Unit (not shown in FIG. 8)

The determining unit is further configured to determine the device identifier according to the forwarding policy before executing the sending unit; and the updating unit is used for updating the service identifier in the BIER message by using the equipment identifier of the second network equipment.

For the specific implementation of the determining unit determining the device identifier in the service identifier and the specific implementation of the updating unit, reference may be made to the detailed description of S303.

For a specific implementation of the sending unit 803, see the detailed description of S303.

For specific implementation of the sending unit 803, see the detailed description of S303

In a possible implementation manner, the extension field further includes the service identifier. For a concrete expression of the extension field, see the detailed description of S303.

For the implementation of the obtaining unit and the determining unit, see the detailed description of S302.

For specific executable functions and implementations of the message transmission apparatus 800, reference may be made to corresponding descriptions about the first network device in the embodiment shown in fig. 3, which is not described herein again.

Fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application, where the communication device may be, for example, a first network device or a second network device in the embodiment shown in fig. 3, or may also be implemented by a device of a multicast packet transmission apparatus 800 in the embodiment shown in fig. 8.

Referring to fig. 9, a communication device 900 includes: a processor 910, a communication interface 920, and a memory 930. The number of the processors 910 in the message forwarding apparatus 900 may be one or more, and fig. 9 illustrates one processor as an example. In the embodiment of the present application, the processor 910, the communication interface 920 and the memory 930 may be connected by a bus system or other means, wherein fig. 9 illustrates the connection by the bus system 940 as an example.

The processor 910 may be a CPU, an NP, or a combination of a CPU and an NP. The processor 910 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a Programmable Logic Device (PLD), or a combination thereof. The PLD may be a Complex Programmable Logic Device (CPLD), a field-programmable gate array (FPGA), a General Array Logic (GAL), or any combination thereof.

The communication interface 920 is used for receiving and sending messages, and in particular, the communication interface 920 may include a receiving interface and a sending interface. The receiving interface may be configured to receive a message, and the sending interface may be configured to send a message. The number of the communication interfaces 920 may be one or more.

The memory 930 may include a volatile memory (english: volatile memory), such as a random-access memory (RAM); the memory 930 may also include a non-volatile memory (english: non-volatile memory), such as a flash memory (english: flash memory), a hard disk (HDD) or a solid-state drive (SSD); the memory 930 may also comprise a combination of memories of the kind described above. The memory 930 may store, for example, the aforementioned correspondence between the identification information and the tunnel.

Optionally, memory 930 stores an operating system and programs, executable modules or data structures, or subsets thereof, or expanded sets thereof, wherein the programs may include various operational instructions for performing various operations. The operating system may include various system programs for implementing various basic services and for handling hardware-based tasks. The processor 910 may read a program in the memory 930 to implement the multicast packet transmission method provided in the embodiment of the present application.

The memory 930 may be a memory device in the communication apparatus 900 or a storage device independent from the communication apparatus 900.

The bus system 940 may be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The bus system 940 may be divided into an address bus, a data bus, a control bus, and the like. For ease of illustration, only one thick line is shown in FIG. 9, but this does not indicate only one bus or one type of bus.

Fig. 10 is a schematic structural diagram of another communication device 1000 provided in this embodiment, where the communication device 1000 may be configured to be implemented as the first network device or the second network device in the foregoing embodiments, or the multicast packet transmission apparatus 800 in the embodiment shown in fig. 8.

The communication device 1000 includes: a main control board 1010 and an interface board 1030.

The main control board 1010 is also called a Main Processing Unit (MPU) or a route processor card (route processor card), and the main control board 1010 controls and manages each component in the communication device 1000, including routing calculation, device management, device maintenance, and protocol processing functions. The main control board 1010 includes: a central processor 1011 and a memory 1012.

The interface board 1030 is also referred to as a Line Processing Unit (LPU), a line card (line card), or a service board. The interface board 1030 is used to provide various service interfaces and to forward packets. The service interfaces include, but are not limited to, Ethernet interfaces, such as Flexible Ethernet services interfaces (FlexE Ethernet Clients), POS (Packet over SONET/SDH) interfaces, and the like. The interface board 1030 includes: a central processor 1031, a network processor 1032, a forwarding table entry memory 1034, and a Physical Interface Card (PIC) 1033.

The central processor 1031 on the interface board 1030 is used for controlling and managing the interface board 1030 and communicating with the central processor 1011 on the main control board 1010.

The network processor 1032 is configured to implement forwarding processing of the packet. The network processor 1032 may take the form of a forwarding chip. Specifically, the processing of the uplink packet includes: processing a message input interface and searching a forwarding table; and (3) downlink message processing: forwarding table lookups, and the like.

The physical interface card 1033 is used to implement the interfacing function of the physical layer, from which the original traffic enters the interface board 1030, and the processed packets are sent out from the physical interface card 1033. Physical interface card 1033 includes at least one physical interface, also referred to as a physical port, physical interface card 1033 corresponding to FlexE physical interface 204 in system architecture 200. The physical interface card 1033, also called a daughter card, may be installed on the interface board 1030, and is responsible for converting the optical signal into a packet, performing validity check on the packet, and forwarding the packet to the network processor 1032 for processing. In some embodiments, the central processor 1031 of interface board 1003 may also perform the functions of network processor 1032, such as implementing software forwarding based on a general purpose CPU, so that network processor 1032 is not required in physical interface card 1033.

Optionally, the communication device 1000 includes a plurality of interface boards, for example, the communication device 1000 further includes an interface board 1040, and the interface board 1040 includes: a central processor 1041, a network processor 1042, a forwarding table entry store 1044, and a physical interface card 1043.

Optionally, the communication device 1000 further comprises a switch screen 1020. The switch board 1020 may also be called a Switch Fabric Unit (SFU). In the case of a communication device having a plurality of interface boards 1030, the switch board 1020 is used to complete the data exchange between the interface boards. For example, interface board 1030 and interface board 1040 can communicate with each other through switch board 1020.

The main control board 1010 and the interface board 1030 are coupled. For example. The main control board 1010, the interface board 1030, the interface board 1040, and the switch board 1020 are connected to the system backplane through a system bus to implement intercommunication. In a possible implementation manner, an inter-process communication protocol (IPC) channel is established between the main control board 1010 and the interface board 1030, and the main control board 1010 and the interface board 1030 communicate with each other through the IPC channel.

Logically, communications device 1000 includes a control plane including main control board 1010 and central processor 1031, and a forwarding plane including various components that perform forwarding, such as forwarding entry memory 1034, physical interface card 1033, and network processor 1032. The control plane performs functions of a router, generating a forwarding table, processing signaling and protocol messages, configuring and maintaining the state of the device, and the like, issues the generated forwarding table to the forwarding plane, and in the forwarding plane, the network processor 1032 looks up the table of the message received by the physical interface card 1033 and forwards the table based on the forwarding table issued by the control plane. The forwarding table issued by the control plane may be stored in the forwarding table entry storage 1034. In some embodiments, the control plane and the forwarding plane may be completely separate and not on the same device.

If communication device 1000 is configured as a first network device, central processor 1011 may obtain a BIER message; a forwarding policy is determined. Network processor 1032 may trigger physical interface card 1033 to send a BIER message to the second network device according to the determined forwarding policy.

If communication device 1000 is configured as a second network device, network processor 1032 may trigger physical interface card 1033 to receive a BIER message.

It should be understood that the sending unit 803 and the like in the message transmission apparatus 800 may correspond to the physical interface card 1033 or the physical interface card 1043 in the communication device 1000; the acquisition unit 801, the determination unit 802, and the like in the message transmitting apparatus 800 may correspond to the central processor 1011 or the central processor 1031 in the communication device 1000.

It should be understood that operations on the interface board 1040 in the embodiment of the present application are the same as those of the interface board 1030, and therefore, for brevity, detailed descriptions are omitted. It should be understood that the communication device 1000 of this embodiment may correspond to the first network device or the second network device in the foregoing various method embodiments, and the main control board 1010, the interface board 1030, and/or the interface board 1040 in the communication device 1000 may implement the functions and/or the various steps implemented by the first network device or the second network device in the foregoing various method embodiments, and therefore, for brevity, no repeated description is provided here.

It should be understood that the main control board may have one or more blocks, and when there are more blocks, the main control board may include an active main control board and a standby main control board. The interface board may have one or more blocks, and the stronger the data processing capability of the communication device, the more interface boards are provided. There may also be one or more physical interface cards on an interface board. The exchange network board may not have one or more blocks, and when there are more blocks, the load sharing redundancy backup can be realized together. Under the centralized forwarding architecture, the communication device does not need a switching network board, and the interface board undertakes the processing function of the service data of the whole system. Under the distributed forwarding architecture, the communication device can have at least one switching network board, and the data exchange among a plurality of interface boards is realized through the switching network board, so that the high-capacity data exchange and processing capacity is provided. Therefore, the data access and processing capabilities of the communication devices of the distributed architecture are greater than those of the devices of the centralized architecture. Optionally, the communication device may also be in the form of only one board card, that is, there is no switching network board, and the functions of the interface board and the main control board are integrated on the one board card, at this time, the central processing unit on the interface board and the central processing unit on the main control board may be combined into one central processing unit on the one board card to perform the function after the two are superimposed, and the data switching and processing capability of the device in this form is low (for example, communication devices such as a low-end switch or a router, etc.). Which architecture is specifically adopted depends on the specific networking deployment scenario.

In some possible embodiments, the first network device or the second network device may be implemented as a virtualized device. For example, the virtualized device may be a Virtual Machine (VM) running a program for sending messages, and the VM is deployed on a hardware device (e.g., a physical server). A virtual machine refers to a complete computer system with complete hardware system functionality, which is emulated by software, running in a completely isolated environment. The virtual machine may be configured as the first network device or the second network device. For example, the first Network device or the second Network device may be implemented based on a common physical server in combination with Network Function Virtualization (NFV) technology. The first network device or the second network device is a virtual host, a virtual router, or a virtual switch. Through reading the present application, a person skilled in the art may combine the NFV technology to virtually generate a first network device or a second network device having the above functions on a general physical server, and details are not described here.

It should be understood that the communication devices in the above various product forms respectively have any functions of the first network device or the second network device in the above method embodiments, and details are not described here.

The embodiment of the application also provides a chip, which comprises a processor and an interface circuit, wherein the interface circuit is used for receiving the instruction and transmitting the instruction to the processor; a processor, which may be a specific implementation form of the multicast message transmission apparatus 800 shown in fig. 8, for example, may be configured to execute the message transmission method described above. Wherein the processor is coupled to a memory for storing a program or instructions which, when executed by the processor, cause the system-on-chip to implement the method of any of the above method embodiments.

Optionally, the system on a chip may have one or more processors. The processor may be implemented by hardware or by software. When implemented in hardware, the processor may be a logic circuit, an integrated circuit, or the like. When implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory.

Optionally, the memory in the system-on-chip may also be one or more. The memory may be integrated with the processor or may be separate from the processor, which is not limited in this application. For example, the memory may be a non-transitory processor, such as a read only memory ROM, which may be integrated with the processor on the same chip or separately disposed on different chips, and the type of the memory and the arrangement of the memory and the processor are not particularly limited in this application.

The system-on-chip may be, for example, a Field Programmable Gate Array (FPGA), an Application Specific Integrated Circuit (ASIC), a system on chip (SoC), a Central Processing Unit (CPU), a Network Processor (NP), a digital signal processing circuit (DSP), a Microcontroller (MCU), a Programmable Logic Device (PLD), or other integrated chips.

An embodiment of the present application further provides a computer-readable storage medium, which includes instructions or a computer program, and when the computer-readable storage medium runs on a computer, the computer is caused to execute the multicast packet transmission method provided in the foregoing embodiment.

Embodiments of the present application further provide a computer program product containing instructions or a computer program, which when run on a computer, causes the computer to execute the multicast packet transmission method provided in the foregoing embodiments.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that the embodiments described herein may be practiced otherwise than as specifically illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the above-described embodiments of the apparatus are merely illustrative, and for example, a division of a unit is only a logical division, and an actual implementation may have another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each service unit in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a hardware form, and can also be realized in a software service unit form.

The integrated unit, if implemented in the form of a software business unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed to by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method of the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

Those skilled in the art will recognize that, in one or more of the examples described above, the services described in this disclosure may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the services may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The above embodiments are intended to explain the objects, aspects and advantages of the present invention in further detail, and it should be understood that the above embodiments are merely illustrative of the present invention.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of multicast message transmission, the method comprising:

a first network device acquires a bit index to display and copy a BIER message, wherein the BIER message comprises a service identifier, the service identifier comprises a Service Level Agreement (SLA) identifier, and the SLA identifier is used for indicating SLA requirements required to be met by forwarding the BIER message;

the first network device determines a forwarding policy corresponding to the service identifier and the device identifier of the second network device according to a corresponding relationship between the service identifier, the device identifier of the second network device and the forwarding policy, the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the forwarding policy corresponding relationship indicates a corresponding relationship between the service identifier and the device identifier of the second network device and the forwarding policy, and the forwarding policy indicates forwarding information meeting the SLA requirement in a process of forwarding the BIER packet to the second network device;

and the first network equipment sends the BIER message to the second network equipment according to the forwarding strategy.

2. The method of claim 1, wherein the service identifier is located in the BIER header.

3. The method of claim 1, wherein the service identifier further includes a device identifier of a network device corresponding to a destination address in the BIER message.

4. The method of claim 3, wherein before the first network device sends the BIER packet to the second network device according to the forwarding policy, the method further comprises:

the first network equipment determines the equipment identification according to the forwarding strategy;

and the first network equipment updates the service identifier in the BIER message by using the equipment of the second network equipment.

5. The method according to any of claims 2 to 4, wherein when a third network device exists between the first network device and the second network device on the forwarding path of the BIER packet, the sending, by the first network device, the BIER packet to the second network device according to the forwarding policy includes:

the first network equipment determines the third network equipment according to the forwarding strategy, wherein the forwarding strategy indicates path information meeting the SLA requirement in the process of forwarding the BIER message to the second network equipment;

and the first network equipment sends the BIER message to the second network equipment through the third network equipment.

6. The method of claim 5, wherein the sending, by the first network device, the BIER packet to the second network device via the third network device comprises:

adding an extension field in the BIER message by the first network equipment, wherein the extension field comprises the equipment identifier of the second network equipment; and the first network equipment forwards the BIER message to the third network equipment, so that the third network equipment forwards the BIER message to the second network equipment according to the equipment identifier of the second network equipment.

7. The method of claim 6, wherein the extension field further comprises the service identification.

8. The method according to claim 6 or 7, wherein when the BIER packet is a BIERv6 packet, the extension field is a segment routing extension header (SRH) field in the BIER packet.

9. The method according to any one of claims 4 to 7, wherein when a third network device supports BIER forwarding, before the first network device determines, according to the service identifier, the device identifier of the second network device, and the forwarding policy correspondence, a forwarding policy corresponding to the service identifier and the device identifier of the second network device, the method further comprises:

the first network equipment acquires a forwarding table entry, and updates a local forwarding table (BIFT) by using the forwarding table entry, wherein the forwarding table entry is used for indicating that the second network equipment is neighbor network equipment of the first network equipment;

and the first network equipment determines second network equipment according to the BIFT.

10. The method of claim 9, wherein the forwarding entry is obtained by the first network device from a controller.

11. A multicast message transmission apparatus, the apparatus comprising:

an obtaining unit, configured to obtain a bit index to display and copy a BIER packet, where the BIER packet includes a service identifier, the service identifier includes a service level agreement SLA identifier, and the SLA identifier is used to indicate an SLA requirement that needs to be met by forwarding the BIER packet;

a determining unit, configured to determine, according to a correspondence between the service identifier and a device identifier of a second network device and a forwarding policy, a forwarding policy corresponding to the service identifier and the device identifier of the second network device, where the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the correspondence between the forwarding policies indicates a correspondence between the service identifier and the device identifier of the second network device and the forwarding policy, and the forwarding policy indicates forwarding information meeting the SLA requirement in a process of forwarding the BIER packet to the second network device;

and the sending unit is used for sending the BIER message to the second network equipment according to the forwarding strategy.

12. The apparatus of claim 11, wherein the service identifier is located in the BIER header.

13. The apparatus of claim 11, wherein the service identifier further includes a device identifier of a network device corresponding to a destination address in the BIER message.

14. The apparatus of claim 13, further comprising: an update unit;

the determining unit is further configured to determine the device identifier according to the forwarding policy before executing the sending unit;

and the updating unit is used for updating the service identifier in the BIER message by using the device identifier of the second network device.

15. The apparatus according to any one of claims 12 to 14, wherein when a third network device exists between the apparatus and the second network device on a forwarding path of the BIER packet, the sending unit is specifically configured to determine the third network device according to the forwarding policy, where the forwarding policy indicates path information that meets the SLA requirement in the process of forwarding the BIER packet to the second network device; and sending the BIER message to the second network equipment through the third network equipment.

16. The apparatus according to claim 15, wherein the sending unit is specifically configured to add an extension field in the BIER packet, where the extension field includes the device identifier of the second network device; and forwarding the BIER message to the third network equipment, so that the third network equipment forwards the BIER message to the second network equipment according to the equipment identifier of the second network equipment.

17. The apparatus of claim 16, wherein the extension field further comprises the service identification.

18. The apparatus according to claim 16 or 17, wherein when the BIER packet is a BIERv6 packet, the extension field is a segment routing extension header (SRH) field in the BIER packet.

19. The apparatus according to any of claims 14 to 17, wherein when a third network device supports BIER forwarding, the obtaining unit is further configured to obtain a forwarding table entry, and update a local forwarding table BIFT with the forwarding table entry, where the forwarding table entry is used to indicate that the second network device is a neighbor network device of the apparatus;

the determining unit is further configured to determine a second network device according to the BIFT.

20. The apparatus of claim 19, wherein the forwarding entry is obtained by the apparatus from a controller.

21. A communication device, the device comprising: a processor and a memory;

the memory for storing instructions or computer programs;

the processor configured to execute the instructions or the computer program in the memory to cause the communication device to perform the method of any one of claims 1-10.

22. A computer-readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform the method of any of claims 1-10 above.