CN114301839B

CN114301839B - Multicast message transmission method and device

Info

Publication number: CN114301839B
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: 2023-05-12
Anticipated expiration: 2040-09-22
Also published as: CN114301839A

Abstract

The embodiment of the application discloses a multicast message transmission method and device, wherein first network equipment acquires a BIER message, the BIER message comprises a service identifier, and the service identifier comprises an SLA identifier for indicating a service level agreement SLA requirement required to be met for forwarding the BIER message. The first network equipment determines a forwarding strategy according to the service identifier, the equipment identifier of the second network equipment and the corresponding relation of the forwarding strategy, wherein the forwarding strategy is used for indicating forwarding information meeting the SLA requirements in the process of forwarding the BIER message to the second network equipment. The first network device sends the BIER message to the second network device according to the forwarding policy. It can be seen that before the first network device forwards the BIER message to the second network device, the corresponding forwarding policy may be determined according to the service identifier and the device identifier of the second network device, and the BIER message is forwarded to the second network device according to the forwarding policy, so as to meet the SLA requirement that needs to be met for forwarding the BIER message.

Description

Multicast message transmission method and device

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to a method and an apparatus for transmitting a multicast packet.

Background

Bit index based display replication (BIER) is a new multicast technique. Compared with the traditional multicast technology, the multicast technology packages the destination node set of the multicast message in a bit string mode to send the message, so that the network intermediate node 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 header. In BIER multicast technology, each destination node is an edge node in a multicast network, taking a network of 256 or less edge nodes as an example, each edge node is configured with a unique value of 1-256, namely an Identity (ID), a destination node set is represented by a 256-Bit string (BitString), and the position of each Bit in the Bit string represents an edge node. The edge nodes can be divided into BIER forwarding ingress routers (Bit forwarding ingress router, BFIR) and BIER forwarding egress routers (Bit forwarding egress router, BFER), and the routes between the BFIR and BFER that support BIER message forwarding are BIER forwarding routers (bit forwarding router, BFR).

For easy understanding of forwarding of BIER messages, refer to a schematic multicast network structure shown in fig. 1, where IDs in a BIER forwarding table (bit index forwarding table, BIFT) in fig. 1 are edge node identifiers. ID-1 refers to PE1, ID-2 refers to PE2, ID-3 refers to PE3, and ID-4 refers to PE4. The forwarding bitmask (Forwarding BitMask, F-BM) represents the set of BIER domain edge nodes reachable through the next-hop neighbor when forwarding the message to the neighbor replication. Neighbor (NBR), a next-hop Neighbor node that represents 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 the P1 node receives the multicast message, searching a forwarding table BIFT corresponding to the P1 node, copying the message, modifying BitString into (0100 and 0011), forwarding the multicast message with BitString being (0100) to PE3, and forwarding the multicast message with BitString being (0011) to P2. After receiving the multicast message, P2 searches its corresponding forwarding table BIFT, copies the message and modifies BitString into (0001 and 0010), forwards the multicast message with BitString into (0001) to PE1, and forwards the multicast message with BitString into (0010) to PE2. Wherein Bit Positions (BP) in BitString represent edge routers.

However, in different application scenarios, there are different service requirements for forwarding BIER packets, and how to meet the service requirements corresponding to the forwarding of BIER packets 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 forwarding a BIER message between BFR and BFR-NBR so as to meet the service requirement of business.

In a first aspect of an embodiment of the present application, a method for transmitting a multicast packet is provided, where the method may include: the method comprises the steps that first network equipment obtains a bit index to display a copy 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 to be met when the BIER message is forwarded; the first network device determines a forwarding policy corresponding to the service identifier and the device identifier of a second network device according to the service identifier, the device identifier of the second network device and the forwarding policy corresponding relation, wherein the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER message, the forwarding policy corresponding relation indicates the corresponding relation 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 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. In this embodiment, the second network device sends the first BGP route information including the service identifier and the identifier of the first network fragment to the first network device, so that the first network device may learn that the first network fragment is used to send the service traffic corresponding to the service identifier to the second network device, so as to meet SLA requirements that need to be met when forwarding the BIER packet.

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

In a possible implementation manner, the service identifier further includes an equipment identifier of a network device corresponding to the destination address in the BIER packet. In this implementation manner, the service identifier may include not only the SLA identifier, but also a device identifier, where the device identifier is a device identifier of a network device corresponding to the destination address in the BIER packet, so as to distinguish different SLA requirements by using the SLA identifier and the device 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 device determines the device identification according to the forwarding strategy; the first network device updates the service identifier in the BIER message with the device of the second network device. In this implementation manner, when the service identifier includes the SLA identifier and the device identifier, because the device identifier is the device identifier of the network device corresponding to the destination address in the BIER packet, and the destination address in the BIER packet is changing, that is, the service identifier is also changing continuously, before the second network device sends the BIER packet to the first network device, the second network device needs to determine the device identifier according to the forwarding policy, so as to update the service identifier, thereby enabling the first network device to identify the service identifier in the BIER packet.

In one possible implementation manner, 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 first network device sends the BIER packet to the second network device according to the forwarding policy, including: the first network device determines the third network device according to the forwarding policy, wherein the forwarding policy indicates path information meeting the SLA requirement in the process of forwarding the BIER message to the second network device; and the first network device sends the BIER message to the second network device through the third network device. In this implementation manner, when a third network device exists between the first network device and the second network device, after determining the forwarding policy, the first network device may determine the third network device according to the forwarding policy, so as to send a BIER packet to the second network device through the third network device. The third network device may be a network device supporting BIER forwarding, or a network device not supporting BIER forwarding. When the third network device is a network device which does not support BIER forwarding, the first network device can sense the existence of the third network device through the forwarding policy, and further send BIER messages to the first network device through the third network device.

In one possible implementation manner, the sending, by the first network device, the BIER packet to the second network device through the third network device includes: the first network device adds an extension field in the BIER message, wherein the extension field comprises the device identifier of the second network device; the first network device forwards the BIER message to the third network device, so that the third network device forwards the BIER message to the second network device according to the device identifier of the second network device. 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 to the second network device after receiving the BIER packet, the first network device may add an extension field to the BIER packet when sending 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 may forward the BIER packet to the second network device according to the device identifier in the extension field after receiving the BIER packet.

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

In one possible implementation, 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 a BIERv6 message, the extension field may be an SRH field in the BIER message.

In a possible implementation manner, when the 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 corresponding relation, a forwarding policy corresponding to the service identifier and the device identifier of the second network device, the method further includes: the first network device acquires a forwarding table entry, updates a local forwarding table BIFT by using the forwarding table entry, and indicates that the second network device is a neighbor network device of the first network device; and the first network equipment determines a second network equipment according to the BIFT. In this implementation manner, when the third network device is a BIER packet forwarding, in a normal case, the third network device is a neighbor network device of the first network device in the local forwarding table BIFT, in order to meet the SLA requirement of the 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 corresponding forwarding table BIFT, and further determine the second network device according to the updated BIFT.

In one possible implementation, the forwarding table entry is obtained by the first network device from a controller. In this implementation, considering that the capability of the first network device is limited, the first network device may update the local forwarding table BIFT by issuing the form of the updated forwarding table entry by the controller.

In a second aspect of the embodiments of the present application, there is provided a multicast message transmission apparatus, where the apparatus includes: the system comprises an acquisition unit, a processing unit and a processing unit, wherein the acquisition unit is used for acquiring a bit index display copy BIER message, 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 the SLA requirement which needs to be met when the BIER message is forwarded; a determining unit, configured to determine a forwarding policy corresponding to the service identifier and the device identifier of a second network device according to the service identifier, a device identifier of the second network device, and a forwarding policy corresponding relation, where the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the forwarding policy corresponding relation indicates a corresponding relation between the service identifier and the device identifier of the second network device, and the forwarding policy indicates forwarding information that satisfies 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 one possible implementation, the service identifier is located in the BIER header.

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

In one possible implementation, the apparatus further includes: an updating unit; the determining unit is further configured to determine, before executing the sending unit, the device identifier according to the forwarding policy; the updating unit is configured to update a service identifier in the BIER packet 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 path information meeting 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.

In a possible implementation manner, the sending unit is specifically configured to add an extension field to 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, the extension field further includes the service identifier.

In one possible implementation, 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, 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.

In one possible implementation, the forwarding table 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, the device comprising: a processor and a memory; the memory is used for storing instructions or computer programs; the processor is configured to execute the instructions or the computer program in the memory, so that the communication device performs the method according to 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 run on a computer, cause the computer to perform the method of the first aspect.

Through 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, wherein the BIER message comprises a service identifier, and the service identifier comprises an SLA identifier for indicating the service level agreement SLA requirement required to be met for 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 service identifier, the device identifier of the second network device, and the forwarding policy correspondence. 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 SLA requirements in a process of forwarding the BIER message to the second network device. The first network device sends the BIER message to the second network device according to the forwarding policy. It can be seen that, by using the multicast message transmission method provided by the embodiment of the present application, before the first network device forwards the BIER message to the second network device, the corresponding forwarding policy may be determined according to the service identifier and the device identifier of the second network device, and because the forwarding information indicated by the forwarding policy may meet the SLA requirement corresponding to the BIER message forwarding process, the first network device may forward the BIER message to the second network device according to the forwarding policy, thereby meeting the SLA requirement that needs to be met for forwarding the BIER message.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of 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 structural diagram of a forwarding policy according to an embodiment of the present application;

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

fig. 3 is a flowchart of multicast message transmission provided in an embodiment of the present application;

fig. 4a is a schematic structural diagram of a multicast packet according to an embodiment of the present application;

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

fig. 4c is a schematic structural diagram of another multicast packet according to an embodiment of the present application;

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

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

fig. 7 is a schematic structural diagram of another forwarding table according to an embodiment of the present application;

fig. 8 is a block diagram of a multicast message transmission device 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 the solution of the present invention better understood by those skilled in the art, the technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments.

Referring to the schematic view of the scenario shown in fig. 2a, in the network system shown in fig. 2a, an example is illustrated that 13 network devices are respectively network device a, network device B, network device C, network device Y, network device Z, network device E, network device F, network device I, network device J, network device K, network device O, network device P, and network device Q. The network device a may be used as a BIER message forwarding ingress router (BFIR), and the corresponding BFR-id=1 (0001), the network device O, the network device P, and the network device Q are used as BIER message forwarding egress routers (BFER), and the corresponding BFR-id=2 (0010), BFR-id=3 (0100), and BFR-id=4 (1000). For network devices located between BFIR and BFER, it may be partly BFR supporting BIER message forwarding and partly network devices not supporting BIER message forwarding. For example, network device Y and network device Z are not capable of BIER message forwarding. In some scenarios, the network device may also be referred to as a node, referring to a device that provides a route forwarding function in the network system, e.g., may be a router, switch, repeater, or label switched router (label switching router, LSR), etc.

In one case, there are different service requirements for forwarding BIER messages, and when the BFR forwards BIER messages to the BFR-NBR, forwarding is required under the condition that the service requirements are met.

In another scenario, there may be multiple paths between the BFR and the BFR-NBR, taking the network structure shown in fig. 2a as an example, there may be two paths from the network device B to the network device C, in order to plan a forwarding path of the BIER packet, in a traffic engineering (BIER-TE) based on display replication of bit indexes, a corresponding identifier is typically allocated to each BFR, for example, a corresponding identifier is allocated to both the network device Y and the network device Z, and the passed BFR identifier on the forwarding path is added to the 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 there are a large number of adjacencies in the BIER-TE network topology, this will result in BitString being too long, affecting the Wen Zaihe rate and forwarding efficiency.

In yet another case, when there is a network device that does not support BIER message forwarding between the BFR and the BFR-NBR, the BFR fails to identify the network device that does not support BIER message forwarding through the forwarding table BIFT when forwarding the BIER message to the BFR-NBR, resulting in failure to implement strict path control. For example, in fig. 2a, the network device Y does not support BIER packet forwarding, and when the forwarding path of the BIER packet is planned to be B-Y-C, the network device B cannot forward the BIER packet according to the forwarding path because there is no information of the network device Y in the forwarding table entry of the network device B.

Based on the above-mentioned problems, the embodiments of the present application provide a multicast message transmission method, which meets SAL requirements corresponding to BIER message forwarding by pre-configuring a forwarding policy. After the first network device receives the BIER message, a corresponding forwarding policy may be determined according to the service identifier, the device identifier of the second network device, and the forwarding policy correspondence. The first network device may forward the BIER message to the second network device according to the forwarding policy, thereby satisfying SAL requirements corresponding to the BIER message. In addition, when the first network device corresponds to a plurality of neighbor network devices, the next-hop neighbor network device can be determined through the pre-acquired forwarding strategy, the identification of the next-hop network device is not required to be carried in the bit string in the BIER message, the load of the BIER message is reduced, and the message forwarding efficiency is improved.

The forwarding policy may BE a forwarding mode meeting SAL requirements corresponding to forwarding BIER packets, where the forwarding mode may include fast forwarding with guaranteed bandwidth (guaranteed bandwidth protocol-expedited forwarding, GBW-EF), guaranteed forwarding with guaranteed bandwidth (guaranteed bandwidth protocol-assured forwarding, GBW-AF), normal fast forwarding (differentiated service-expedited forwarding, DS-EF), normal guaranteed forwarding (differentiated service-assured forwarding, DS-AF), best effort forwarding (BE, BE), and the like. Or, the forwarding policy may also be a forwarding path that satisfies SAL requirements corresponding to forwarding BIER packets. In this case, the controller may collect the topology of the current network system through a border gateway link state (BGP-LS) protocol and calculate routes according to a service-level agreement (SLA). And meanwhile, forwarding policy is issued for nodes which need to specify forwarding paths to meet the SLA requirements. The controller issues two forwarding policies to the node B as in fig. 2B to specify different paths for BIER messages requiring different SLAs to the node C. And simultaneously, three forwarding policies are issued to the C node to specify forwarding paths corresponding to different BFER. Specifically, the controller may issue forwarding policies policy only for the node with the bifurcation path, or issue forwarding policies for all BFRs on the multicast forwarding path, so as to implement strict path control, and the embodiment of issuing a routing policy by the controller is not limited herein. For example, the network device B may determine, through a forwarding policy, 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 in the embodiments of the present application may be any two network devices supporting BIER packet forwarding in the network transmission system. Specifically, the first network device and the second network device may be neighbor network devices to each other. For example, the network structure shown in fig. 2a, the first network device is a network device a, and the second network device is a network device B. Or the first network device is a network device B, the second network device is a network device C, wherein the network device Y and the network device Z are neighbor network devices which do not support BIER message forwarding. Or, the network device a, the network device B and the network device C all support BIER message forwarding, but in a specified manner, the network device C is a neighbor network device of the network device a, where 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 be a multicast message in an IPv6 network.

For easy understanding, the following will describe an example of a network system structure shown in fig. 2a, referring to fig. 3, which is a flowchart of a multicast message transmission method provided in an embodiment of the present application, as shown in fig. 3, the method may include:

S301: the first network device obtains a BIER message, the BIER message including a service identifier.

In this embodiment, the first network device first obtains a BIER packet, where the BIER packet includes a service identifier, where the service identifier includes a service level agreement (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 requirement may be a bandwidth, a delay, a jitter rate, and so on.

Specifically, the service identifier may be determined according to the service type to which the BIER message belongs, where different service types correspond to different service identifiers, and different service identifiers correspond to different SLA requirements. The service types may include video, audio, text, etc., among others. The service identifier is a first identifier, the first identifier can identify color, and the color identifier is used for representing specific SAL requirements. The color identification color may be encapsulated in a header of the BIER message. Alternatively, the first identification may be a differentiated service coding point (differentiated services code point, DSCP), which may guarantee the quality of service (quality of service, qoS) of the communication, the service class being divided by coding in 8 identification bytes of the IP header of the BIER message. Or, the service identifier may also be a second identifier, where the second identifier may include an SAL identifier and a device identifier, where the device identifier is a device identifier of a network device corresponding to a destination address in the BIER packet. The implementation of the concrete expression form of the service identifier will be described in the following embodiments.

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

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

Specifically, when the controller issues a forwarding policy to the first network device, the controller may issue a correspondence between the service identifier, the device identifier of the second network device, and the forwarding policy, and when the first network device obtains the service identifier and the device identifier of the second network device, the controller may determine the forwarding policy according to the correspondence between the service identifier, the device identifier of the second network device, and the forwarding policy. For example, as shown in fig. 2B, the first network device is a network device B, and determines a forwarding policy1 according to the service identifier, the device identifier of the second network device (such as network device C), and the forwarding policy correspondence, where the policy1 indicates that the BIER message is forwarded to the network device C, and then passes through the network device Y. When the first network device is the network device C, determining a forwarding policy2 according to the service identifier, the device identifier of the second network device (such as the network device O) and the forwarding policy corresponding relation, and when the policy2 indicates to forward the BIER message to the network device O, the BIER message passes through the network device E and the network device I.

In a specific embodiment, 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 correspondence, the first network device further needs to determine the second network device. Specifically, the first network device determines the second network device according to the bit string Bitstring and the forwarding table BIFT in the BIER message. The bit string BitString may include only the device identifier of the BIER packet forwarding egress network device (e.g., the device identifier including the network device O, the network device P, and the network device Q). Wherein, in one case, the forwarding table BIFT may be a forwarding table stored in advance locally for the first network device, where the forwarding table is used to indicate a neighboring network device that is adjacent to the first network device and supports forwarding of BIER packets. For example, the first network device is a network device a, and its corresponding neighbor network device is a 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 neighboring network device of the first network device. Specifically, the controller may designate a neighbor network device according to the SLA corresponding to the BIER packet and the network topology, and issue a forwarding table entry 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 can determine the second network device according to the bit string and the updated BIFT. Referring to the application scenario schematic diagram shown in fig. 2C, the first network device is a network device a, both the network device B and the network device C support BIER message forwarding, and the neighbor network device of the designated network device a in the forwarding table updated on the network device a is a network device C, and then the second network device is a network device C.

S303: the first network device sends the BIER message to the second network device according to the forwarding policy.

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 when forwarding the BIER packet.

In one case, when the forwarding policy is a forwarding mode that satisfies the SLA requirement corresponding to forwarding the BIER packet, the first network device sends the BIER packet to the second network device according to the forwarding mode. For example, if the forwarding policy is to ensure fast forwarding of the GBW-EF of the 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 the corresponding SLA requirement for forwarding the BIER packet. The first network device determines a third network device according to the forwarding policy, and the first network device sends a BIER message to the second network device through the third network device. The third network device may be a network device supporting BIER forwarding, as shown in fig. 2C, where the first network device is a network device a, the second network device is a network device C, and the determined forwarding policy1 is determined, and the third network device determined by the policy1 is a network device B and a 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 at this time, the forwarding policy may indicate the third network device. As shown in fig. 2B, 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, so that it may be determined by policy1 that the network device B will forward the BIER message to the network device C through the network device Y.

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

in one case, when the service identifier is a first identifier, such as a color identifier, the first identifier may be globally used in the network system without updating the first identifier. The first network device may modify only the destination address (destination address, DA) in the BIER message to the address of the second network device. Taking BIERv6 packet as an example, for example, as shown in fig. 4a, 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 packet to the network device B, the IPv6 destination address DA is modified to the address of the network device B. 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. As another example, as shown in fig. 4a, the first network device is a network device B, the second network device is a network device C, and the third network device is a network device Y, and the network device B modifies the IPv6 destination address DA in the BIER packet to the address of the network device Y. After receiving the BIER message, the network device Y modifies the IPv6 destination address DA in the BIER message into the address of the network device C and forwards the modified address to the network device 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, before forwarding the BIER packet to the third network device, the first network device may further add an extension field to the BIER packet, where the extension field may include a device identifier of the second network device, so that after receiving the BIER packet, the third network device forwards the BIER packet to the second network device through the device identifier of the second network device. Taking the BIEv6 packet as an example, as shown in fig. 4a, when the network device B forwards the BIER packet to the network device Y, the extension field is a segment routing extension header (segment routing header, SRH) field of the BIER packet, and the SRH field is added with the device identifier of the network device C. After receiving the BIER message, the network device Y determines the network device C according to the device identifier in the SRH, and forwards the BIER message to the 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 may be forwarded to the second network device. For example, in fig. 4a, network device Y deletes the SRH and forwards the BIER message to network device C. Taking BIERv4 packet as an example, in a multiprotocol label switching (multi-protocol label switching, MPLS) network in particular, the extension field may be a label in the BIER packet, where 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), which may be an internet protocol (Internet protocol, IP) address or a loopback back address of the network device.

In another case, when the service identifier includes an SLA identifier and a device identifier, where the device identifier and the identifier are identifiers of network devices corresponding to a destination address in the BIER message. According to the method, the destination address in the BIER message is continuously updated, so that when the first network device forwards the BIER message to the second network device, the first network device 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 particular implementations, the first network device may determine the device identification of the second network device according to a forwarding policy that includes the device identification of the second network device. For example, as shown in FIG. 4B and FIG. 4C, the first network device is network device B, the second network device is network device C, and the service identifier in the BIER message sent by the network device A is 1, where B is the device identifier of the network device B, and 1 is the SLA identifier. When the forwarding policy determined by the network equipment according to the service identifier and the equipment identifier of the network equipment C is poll 1, the service identifier can be known to be C:1 through the poll 1. The network device B modifies the service identifier B:1 in the BIER message to C:1, and 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 a previous hop network device according to an SLA requirement corresponding to the BIER message, or acquired by the previous hop network device from the controller.

In this case, the first network device also needs to modify the destination address of the BIER message to the address of the second network device. 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 packet as an example, as shown in fig. 4C, 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, then the network device B modifies the IPv6 destination address DA in the BIER packet to the address of network device Y. After receiving the BIER message, the network device Y modifies the IPv6 destination address DA in the BIER message into the address of the network device C and forwards the modified address to the network device 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, before forwarding the BIER message to the third network device, the first network device may further add a device identifier of the second network device to the BIER message, so that after receiving the BIER message, the third network device forwards the BIER message to the second network device through the device identifier of the second network device. In this case, the first network device will add the device identification of the second network device in the SRH of the BIER message, as shown in fig. 4c for example.

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

For ease of understanding, a specific implementation corresponding to the embodiment of the present application will be described below with reference to the network structure shown in fig. 2 a. Referring to fig. 5, the flowchart of another multicast message transmission method provided in the embodiment of the present application is shown in fig. 5, where in the method, a service identifier is taken as a first identifier, for example, a color identifier is illustrated, and may include:

S501: the network equipment A acquires the BIER message.

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

S502: the network device a sends BIER message to the network device B.

After the network device a adds the color identifier color message in the BIER message, the neighbor network device, i.e. the network device B, can be determined according to the bit string in the BIER message and the forwarding table BIFT. And simultaneously, modifying the destination address in the BIER message into the address of the network equipment B, and forwarding the BIER message to the network equipment B. For example, the BIERv6 message shown in fig. 4a is used to modify the IPv6 destination address DA into the address of the network device B.

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

When the network device B receives the BIER message sent by the network device a, it may determine, according to the forwarding table BIFT, the network device that supports forwarding of the BIER message by the next hop, that is, the network device C.

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

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

In this embodiment, the controller may issue a forwarding policy to the network device B, and issue a correspondence between the forwarding policy and the device identifier and the color identifier. When the network equipment B determines the network equipment C, a forwarding strategy is determined according to the equipment identification, the color identification color and the corresponding relation of the network equipment C. Regarding the implementation of the network device B to determine the forwarding policy based on the device identification and the color identification of the network device C, reference may be made to the relevant description of S302.

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

When the network device B determines the forwarding policy, the next-hop network device, i.e. the network device Y, may be determined 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 to 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 forward normally, when the network device B forwards the BIER message to the network device Y, the device identifier of the network device C is added to the BIER message, so that the network device Y can forward subsequently according to the device identifier of the network device C. Specifically, the network device B may add the device identifier of the network device C to the SRH in the BIER message. As in fig. 4a, the address of the network device C is carried in the SRH of the BIER message. The specific implementation of adding the device identifier to the network device B may be referred to as 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 the network device Y receives the BIER message forwarded by the network device B, the next-hop network device, i.e. the network device C, may be determined according to the device identifier carried by the SRH in the BIER message, so as to forward the BIER message to the next network device. Specifically, when forwarding the BIER message 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 message to the address of the network device C. As shown in fig. 4 a.

S507: 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 message is copied, so as to forward the BIER message to each egress network device respectively. The specific implementation of determining the network device P and the network device O according to the forwarding table BIFT with respect to the network device C may be referred to S503.

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

S509: the network device C determines a corresponding second forwarding strategy according to the device identifier of the network device O and the color 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 and the color identifier of the network device P. As shown in fig. 2b, the network device C matches the forwarding policy1 according to the device identifier and the color identifier of the network device P; and matching the color to a forwarding policy2 according to the device identification and the color identification of the network device O. The specific implementation of the forwarding policy determined by the network device C according to the device identifier and the color identifier may be referred to S504.

S510: 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, the network device C sends two BIER messages to the network device E, where 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 device identifier carried by the SRH is related to the determined forwarding strategy. For example, as shown in fig. 2b, a first BIER packet sent to the network device P corresponds to a first forwarding policy1, paths corresponding to the policy1 are E, J and P, and an SRH of the first BIER packet includes device identifiers of the network device P and the network device J; and the second BIER message sent to the network device O corresponds to a second forwarding policy2, paths corresponding to the policy2 are E, I and O, and the SRH of the second BIER message includes the device identifier of the network device O and the device identifier of the network device I. Wherein, reference may be made to S505 for a specific implementation in which the network device C determines the network device E according to the first forwarding policy or the second forwarding policy.

S512: 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 of 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.

Among them, specific implementations with respect to S512, S513, and S514 can be seen from S506.

Referring to fig. 6, which is a flowchart of another multicast message transmission method provided in the embodiment of the present application, as shown in fig. 6, in this embodiment, a service identifier includes a device identifier and an SLA identifier is taken as an example, and specifically, in connection with fig. 4b, 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 packet sent by a previous hop network device (such as a user device) or generates a BIER packet by itself, a corresponding forwarding policy may be determined according to an SLA requirement corresponding to an SLA identifier included in a service identifier in the BIER packet. The forwarding policy may be used to indicate a device identifier of a network device corresponding to forwarding the BIER packet, where the device identifier may satisfy a quality of service required for forwarding the BIER packet. Specifically, the controller may issue a forwarding policy to the network device a, and a correspondence 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 correspondence. As shown in fig. 4b, the forwarding policies policy1 and forwarding policy2 are issued at the network device a.

S602: the network equipment A updates the service identification 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. When the network device A determines a forwarding policy1, this policy1 specifies a traffic identity B:1, as shown in FIG. 4B. Wherein, B:1 and B:2 point to network equipment B, and 1 and 2 respectively represent different SLA identifications.

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 service identifier in the BIER message may be updated by using the updated request identifier, and then the destination address in the BIER message is modified to the address of the network device B, so as to 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 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 a specific implementation of S604, reference may be made to the detailed description of S503, which is not repeated here in this embodiment.

S605: 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 correspondence 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 packet. As shown in FIG. 4B, the network device B determines a corresponding forwarding policy1 according to the device identification of the network device C and the service identification B:1.

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

When 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. In FIG. 4b, the service identifier corresponding to poliy 1 is C:1, and the next hop network device is Y; the business mark corresponding to the policy2 is C:2, and the next hop network equipment is Z. The present embodiment will be described with reference to the next hop network device being 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 learn that the BIER packet is forwarded to the network device C through the device identifier, before forwarding the BIER packet 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 to the address of the network device Y. The format of the BIER message sent by network device B to network device Y is shown in fig. 4 c. For implementation of forwarding the BIER message from the network device B to the network device Y, see S505.

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

When the network device Y receives the BIER message forwarded by the network device B, the next-hop network device, i.e. the network device C, may be determined according to the extension field in the BIER message, and then forwarded to the BIER message to the network device C. Specifically, when forwarding the BIER message 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 message to the address of the network device C. Such as the format of BIER message sent by network device Y to network device C in fig. 4C.

S608: 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 a specific implementation of S608, reference may be made to S507, which is not described herein.

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

S610: the network device C determines a second forwarding policy according to the device identifier of the network device 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 policies. After the network equipment C receives the BIER message, a first forwarding strategy can be determined according to the equipment identifier of the network equipment P and the service identifier C in the BIER message, wherein 1 is the number of the equipment identifier and the corresponding relation; and determining a second forwarding strategy according to the equipment identifier of the network equipment O, the service identifier C in the BIER message, namely 1 and the corresponding relation. For example, as shown in FIG. 4b, network device C matches forwarding policy1 based on device identification P and C::1 of network device P and matches forwarding policy 2 based on device identification O and C::1 of network device O. The specific implementation of S609 and S610 may be referred to S509.

S611: 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, where 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 device identifier carried by the SRH is related to the determined forwarding strategy. For example, a first BIER packet sent to the network device P corresponds to a first forwarding policy1, paths corresponding to the policy1 are E, J and P, and an SRH of the first BIER packet includes device identifiers of the network device P and the network device J; and the second BIER message sent to the network device O corresponds to a second forwarding policy2, paths corresponding to the policy2 are E, I and O, and the SRH of the second BIER message includes the network device O and the network device I.

The specific implementation of the network device C to determine the network device E according to the first forwarding policy or the second forwarding policy may be referred to as S505, S510, or S511.

S613: 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: the network device J forwards the first BIER message to the network device P according to the device 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.

Wherein, see the relevant description of S607 for specific implementation of S613-S615.

In addition, in order to solve the problem that BIER messages cannot be effectively forwarded due to multiple paths 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, the embodiment of the present invention further provides another solution, specifically, in the forwarding table, the specified forwarding path information is newly added in the BIFT, and when the first network equipment receives the BIER message, a specific forwarding path can be obtained by searching the BIFT of the forwarding table, so that the BIER message is forwarded according to the forwarding path. The specific implementation can include: the first network equipment acquires a 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. When 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 the BIER message to the network equipment C according to the forwarding path B-Y-C.

In a specific embodiment, the first network device further determines the second network device before determining the forwarding path according to the bit string of the BIER message, the device identifier of the second network device, and the forwarding table. Specific implementations of the first network device determination of the second network device may be found in the relevant description of S302. For a specific implementation of the first network device sending the BIER message to the second network device, reference may be made to the relevant description of S303.

Based on the above method embodiments, the embodiments of the present application further provide a multicast message transmission device, and the device 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 the embodiment of the present application, the apparatus 800 may be applied to a first network device, perform a function of the first network device in the embodiment shown in fig. 3, and 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, and display a duplicate BIER packet, where the BIER packet includes a service identifier, where 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 satisfied when forwarding the BIER packet.

The specific implementation of the obtaining unit 801 may be referred to in the embodiment shown in fig. 3 as a detailed description of S301.

A determining unit 802, configured to determine a forwarding policy corresponding to the service identifier and the device identifier of a second network device according to the service identifier, the device identifier of the second network device, and a forwarding policy corresponding relation, where the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the forwarding policy corresponding relation indicates a corresponding relation 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 be referred to in the embodiment shown in fig. 3 as a detailed description of S302.

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

The detailed description of S303 may be found with reference to the embodiment shown in fig. 3 for the specific implementation of the transmitting unit 803.

In one possible implementation, the service identifier is located in the BIER header. See the detailed description of S301 for encapsulation formats of service identities in BIER messages.

In a possible implementation manner, the service identifier further includes an equipment identifier of a network device corresponding to the destination address in the BIER packet. See the detailed description of S301 for encapsulation formats of service identities in BIER messages.

In one possible implementation, the apparatus further includes: update unit (not shown in fig. 8)

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

The detailed description of S303 may be referred to for a specific implementation of the determining unit for determining the device identifier in the service identifier and a specific implementation of the updating unit.

Here, a detailed description of S303 may be referred to with respect to a specific implementation of the transmission unit 803.

Wherein, the detailed description of S303 can be seen with respect to the specific implementation of the sending unit 803

In a possible implementation, the extension field further includes the service identifier. The detailed description of S303 may be referred to for the specific expression form of the extension field.

Among them, reference may be made to the detailed description of S302 regarding the implementation of the acquisition unit and the determination unit.

For specific executable functions and implementations of the packet transmission apparatus 800, reference may be made to the corresponding description of the first network device in the embodiment shown in fig. 3, which is not repeated here.

Fig. 9 is a schematic structural diagram of a communication device provided in the 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 a device implementation of the multicast packet transmission apparatus 800 in the embodiment shown in fig. 8.

Referring to fig. 9, a communication apparatus 900 includes: a processor 910, a communication interface 920, and a memory 930. Where the number of processors 910 in message forwarding device 900 may be one or more, one processor is illustrated in fig. 9. In the present embodiment, processor 910, communication interface 920, and memory 930 may be connected by a bus system or other means, with a bus system 940 being shown in FIG. 9 as an example.

The processor 910 may be a CPU, an NP, or a combination of a CPU and 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 (programmable logic device, PLD), or a combination thereof. The PLD may be a complex programmable logic device (complex programmable logic device, CPLD), a field-programmable gate array (field-programmable gate array, FPGA), general-purpose array logic (generic array logic, GAL), or any combination thereof.

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

Memory 930 may include volatile memory (English) such as random-access memory (RAM); the memory 930 may also include a nonvolatile memory (english: non-volatile memory), such as a flash memory (english: flash memory), a hard disk (HDD) or a Solid State Drive (SSD); memory 930 may also include combinations of the above types of memory. The memory 930 may store, for example, the correspondence between the aforementioned identification information and the tunnel.

Optionally, the memory 930 stores an operating system and programs, executable modules or data structures, or a subset thereof, or an extended set thereof, where the programs may include various operational instructions for implementing various operations. The operating system may include various system programs for implementing various underlying services and handling hardware-based tasks. The processor 910 may read the program in the memory 930, to implement the multicast message transmission method provided in the embodiment of the present application.

The memory 930 may be a memory device in the communication device 900 or may be a memory device independent of the communication device 900.

The bus system 940 may be a peripheral component interconnect (peripheral component interconnect, PCI) bus or an extended industry standard architecture (extended industry standard architecture, EISA) bus, among others. 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 not only one bus or one type of bus.

Fig. 10 is a schematic structural diagram of another communication device 1000 provided in the embodiment of the present application, where the communication device 1000 may be configured as the first network device or the second network device in the foregoing embodiments, or implemented as a device of 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 (main processing unit, MPU) or a routing processing card (route processor card), and the main control board 1010 controls and manages various components in the communication device 1000, including routing computation, device management, device maintenance, and protocol processing functions. The main control board 1010 includes: a central processing unit 1011 and a memory 1012.

Interface board 1030 is also referred to as a line interface unit card (line processing unit, LPU), line card, or service board. Interface board 1030 is used to provide various service interfaces and to enable forwarding of data packets. The service interfaces include, but are not limited to, ethernet interfaces, such as flexible ethernet service interfaces (Flexible Ethernet Clients, flexE Clients), POS (Packet over SONET/SDH) interfaces, etc. Interface board 1030 includes: a central processor 1031, a network processor 1032, a forwarding table entry memory 1034, and a physical interface card (ph 8sical interface card, PIC) 1033.

Central processor 1031 on interface board 1030 is used to control and manage interface board 1030 and communicate with central processor 1011 on main control board 1010.

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

The physical interface card 1033 is used to implement the docking function of the physical layer, from which the original traffic enters the interface board 1030, and from which the processed messages are sent out from the physical interface card 1033. The physical interface card 1033 includes at least one physical interface, also referred to as a physical interface, the physical interface card 1033 corresponding to the FlexE physical interface 204 in the system architecture 200. The physical interface card 1033, also called a daughter card, may be mounted on the interface board 1030 and is responsible for converting the photoelectric signals into messages and forwarding the messages to the network processor 1032 for processing after the messages are legally checked. In some embodiments, the central processor 1031 of the interface board 1003 may also perform the functions of the network processor 1032, such as implementing software forwarding based on a general purpose CPU, so that the network processor 1032 is not required in the physical interface card 1033.

Optionally, the communication device 1000 includes a plurality of interface boards, e.g., the communication device 1000 further includes an interface board 1040, the interface board 1040 including: 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 switching fabric 1020. The switch fabric 1020 may also be referred to as a switch fabric unit (switch fabric unit, SFU). In the case of a communication device having multiple interface boards 1030, the switching fabric 1020 is configured to perform data exchanges between the interface boards. For example, interface board 1030 and interface board 1040 may communicate via switch fabric 1020.

The main control board 1010 and the interface board 1030 are coupled. For example. Main control board 1010, interface board 1030 and interface board 1040 are connected with system back board by system bus to realize intercommunication. In one possible implementation, an inter-process communication protocol (inter-process communication, IPC) channel is established between the main control board 1010 and the interface board 1030, and communication is performed between the main control board 1010 and the interface board 1030 through the IPC channel.

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

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

It should be understood that the sending unit 803 and the like in the packet 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 packet transfer apparatus 800 may correspond to the central processor 1011 or the central processor 1031 in the communication device 1000.

It should be understood that the operations on the interface board 1040 are consistent with the operations of the interface board 1030 in the embodiment of the present application, and for brevity, will not be described again. 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 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 implemented steps of the first network device or the second network device in the foregoing method embodiments, which are not described herein for brevity.

It should be understood that the master control board may have one or more pieces, and that the master control board may include a main master control board and a standby master control board when there are more pieces. The interface boards may have one or more blocks, the more data processing capabilities the communication device is, the more interface boards are provided. The physical interface card on the interface board may also have one or more pieces. The switching network board may not be provided, or may be provided with one or more blocks, and load sharing redundancy backup can be jointly realized when the switching network board is provided with the plurality of blocks. Under the centralized forwarding architecture, the communication device does not need to exchange network boards, and the interface board bears the processing function of the service data of the whole system. Under the distributed forwarding architecture, the communication device may have at least one switching fabric, through which data exchange between multiple interface boards is implemented, providing high-capacity data exchange and processing capabilities. Therefore, the data access and processing power of the communication device of the distributed architecture is greater than that of the device of the centralized architecture. Alternatively, the communication device may be in the form of only one board card, i.e. there is no switching network board, the functions of the interface board and the main control board are integrated on the one board card, and the central processor on the interface board and the central processor on the main control board may be combined into one central processor on the one board card, so as to execute the functions after stacking the two, where the data exchange and processing capability of the device in this form are low (for example, the communication device such as a low-end switch or a router). 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 message functions, the Virtual Machine deployed on a hardware device (e.g., a physical server). Virtual machines refer to complete computer systems that run in a completely isolated environment with complete hardware system functionality through software emulation. The virtual machine may be configured as a first network device or a second network device. For example, the first network device or the second network device may be implemented based on a generic physical server in combination with network function virtualization (Network Functions Virtualization, NFV) technology. The first network device or the second network device is a virtual host, a virtual router, or a virtual switch. By reading the application, a person skilled in the art can virtually obtain the first network device or the second network device with the above functions on the general physical server by combining with the NFV technology, which is not described herein again.

It should be understood that the communication devices in the above various product forms have any function of the first network device or the second network device in the above method embodiment, and are not described herein.

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, such as one implementation of the multicast messaging device 800 illustrated in fig. 8, may be used to perform the method of messaging described above. Wherein the processor is coupled to a memory for storing programs or instructions which, when executed by the processor, cause the system-on-a-chip to implement the method of any of the method embodiments described above.

Alternatively, the processor in the system-on-chip may be one or more. The processor may be implemented in hardware or in 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.

Alternatively, the memory in the system-on-chip may be one or more. The memory may be integral with the processor or separate from the processor, and is not limited in this application. For example, the memory may be a non-transitory processor, such as a ROM, which may be integrated on the same chip as the processor, or may be separately provided on different chips, and the type of memory and the manner of providing the memory and the processor are not specifically limited in this application.

The system-on-chip may be, for example, a field programmable gate array (field programmable gate array, FPGA), an application specific integrated chip (application specific integrated circuit, ASIC), a system on chip (SoC), a central processing unit (central processor unit, CPU), a network processor (network processor, NP), a digital signal processing circuit (digital signal processor, DSP), a microcontroller (micro controller unit, MCU), a programmable controller (programmable logic device, PLD) or other integrated chip.

The present application also provides a computer readable storage medium including instructions or a computer program, which when run on a computer, causes the computer to execute the multicast message transmission method provided in the above embodiment.

The present embodiments also provide a computer program product comprising instructions or a computer program, which when run on a computer, causes the computer to perform the multicast message transmission method provided in the above embodiments.

The terms "first," "second," "third," "fourth" and the like in the description and in the claims of this application and in the above-described figures, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments described herein may be implemented in other sequences than those illustrated or otherwise 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 will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, e.g., the division of units is merely a logical service division, and there may be additional divisions in actual implementation, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each service unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software business units.

The integrated units, if implemented in the form of software business units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be embodied in essence or a part contributing to the prior art or all or part of the technical solution in the form of a software product stored in a storage medium, including several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods 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, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

Those skilled in the art will appreciate that in one or more of the examples described above, the services described herein may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the services may be stored in a computer-readable medium or transmitted 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 objects, technical solutions and advantageous effects of the present invention have been described in further detail in the above embodiments, and it should be understood that the above are only embodiments of the present invention.

The above embodiments are only for illustrating the technical solution of the present application, and not for limiting 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 scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. The multicast message transmission method is characterized by comprising the following steps:

the method comprises the steps that first network equipment obtains a bit index to display a copy 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 to be met when the BIER message is forwarded;

the first network device determines a forwarding policy corresponding to the service identifier and the device identifier of a second network device according to the service identifier, the device identifier of the second network device and the forwarding policy corresponding relation, wherein the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER message, the forwarding policy corresponding relation indicates the corresponding relation 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 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.

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

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

4. The method of claim 3, wherein prior to the first network device sending the BIER message to the second network device according to the forwarding policy, the method further comprises:

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

the first network device updates the service identifier in the BIER message with the device of the second network device.

5. The method according to any one of claims 2-4, when there is a third network device between the first network device and the second network device on a forwarding path of the BIER packet, the first network device sending the BIER packet to the second network device according to the forwarding policy, including:

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

And the first network device sends the BIER message to the second network device through the third network device.

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

the first network device adds an extension field in the BIER message, wherein the extension field comprises the device identifier of the second network device; the first network device forwards the BIER message to the third network device, so that the third network device forwards the BIER message to the second network device according to the device identifier of the second network device.

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

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

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

The first network device acquires a forwarding table entry, updates a local forwarding table BIFT by using the forwarding table entry, and indicates that the second network device is a neighbor network device of the first network device;

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

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

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

the system comprises an acquisition unit, a processing unit and a processing unit, wherein the acquisition unit is used for acquiring a bit index display copy BIER message, 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 the SLA requirement which needs to be met when the BIER message is forwarded;

a determining unit, configured to determine a forwarding policy corresponding to the service identifier and the device identifier of a second network device according to the service identifier, a device identifier of the second network device, and a forwarding policy corresponding relation, where the second network device is a network device supporting BIER forwarding on a forwarding path of the BIER packet, the forwarding policy corresponding relation indicates a corresponding relation between the service identifier and the device identifier of the second network device, and the forwarding policy indicates forwarding information that satisfies 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 identification is located in the BIER header.

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

14. The apparatus of claim 13, wherein the apparatus further comprises: an updating unit;

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

the updating unit is configured to update a service identifier in the BIER packet by using the device identifier of the second network device.

15. The apparatus according to any one of claims 12-14, 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 meeting the SLA requirement in a 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 configured to specifically add an extension field in the BIER message, the extension field including 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 identity.

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

19. The apparatus according to any one of claims 14-17, when a third network device supports BIER forwarding, the obtaining unit further configured to obtain a forwarding table entry, 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 table entry is obtained by the apparatus from a controller.

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

the memory is used for storing instructions or computer programs;

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

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