CN111917651A - Multicast forwarding method and system for cross chip - Google Patents

Abstract

The invention discloses a cross-chip multicast forwarding method and system, and relates to the technical field of packet switching. In the present invention, in the case of a new definition of a converged multicast group, a converged multicast group is used to carry a plurality of chips with the same purpose. The service multicast group greatly reduces the design consumption of multicast forwarding on the cross chip. When the inbound service chip receives the service to be forwarded, it searches the multicast mapping table from the service multicast group to the aggregation multicast group to obtain the corresponding aggregation multicast group, and adds the corresponding aggregation group before the service multicast header in the packet. When the cross-connect chip receives the packet, it performs multicast forwarding according to the aggregated multicast group header; when the outbound service chip receives the packet, it strips the aggregated multicast group header and forwards the service multicast group. The cross-connect chip is not sensitive to multicasting any information, and only performs multicast forwarding between chips based on the aggregated multicast group header, which greatly reduces the hardware consumption of the cross-connect chip.

Description

Multicast forwarding method and system for cross chip

technical field

The invention relates to the technical field of packet switching, in particular to a method and system for multicast forwarding of a cross chip.

Background technique

Multicast is a common service model in packet switching, and forwarding nodes need to complete one-to-many packet replication and forwarding. At present, in rack-mounted equipment, the distributed multicast implementation method is completed by the service chip and the cross chip, and the multicast design of the cross chip is often directly associated with the service multicast group to complete each multicast forwarding between chips. So as to achieve the purpose of forwarding multicast services. The feature is that the multicast table of the cross-connect chip is the same size as the service multicast group. The number of services required depends on the number of service multicast groups.

SUMMARY OF THE INVENTION

In view of the defects existing in the prior art, the purpose of the present invention is to provide a method and system for multicast forwarding of a cross chip, which greatly reduces the design consumption of multicast forwarding on the cross chip.

In order to achieve the above purpose, the technical scheme adopted by the present invention is: a method for multicast forwarding of cross-chips, comprising the following steps:

Create an aggregation multicast group entry and configure it on the cross-connect chip, the aggregation multicast group entry includes all possible aggregation multicast groups, and each aggregation multicast group is a chip distribution combination in the outbound direction;

According to the chip distribution of each service multicast group, obtain the aggregation multicast group corresponding to the service multicast group, generate a multicast mapping table from the service multicast group to the aggregation multicast group, and configure it to the service chip;

When the service chip in the inbound direction receives the service to be forwarded, it searches the multicast mapping table to obtain the corresponding aggregation multicast group, adds the corresponding aggregation multicast group header before the service multicast header in the packet, and sends it to the cross-connect chip;

When the cross-connect chip receives the packet, it performs multicast forwarding according to the aggregated multicast group header and the aggregated multicast group entry;

When the outbound service chip receives the packet, it strips the aggregation multicast group header and forwards the service multicast group.

其中，n为所有入方向和出方向的业务芯片的总和。Based on the above technical solutions, when creating an aggregation multicast group entry, the total number of all possible aggregation multicast groups is:

Among them, n is the sum of all inbound and outbound service chips.

On the basis of the above technical solution, the composition fields of the converged multicast group header include: message type, source chip and converged multicast group; the composition fields of the service multicast header include: service type, service multicast group .

On the basis of the above technical solutions, the service chips in the inbound direction are distributed according to the chips corresponding to each service multicast group to obtain the aggregation multicast group corresponding to the service multicast group, including the following steps:

Multicast the service to all chips corresponding to the service;

According to the standard service multicast group join message, the corresponding chip distribution of the service multicast group of each service is obtained, and the aggregation multicast group with the same chip distribution is found from the aggregation multicast group entry as the service multicast group. The corresponding aggregation multicast group.

Based on the above technical solution, when the cross-connect chip receives the packet, it performs multicast forwarding according to the aggregated multicast group header and the aggregated multicast group entry, which specifically includes the following steps:

When the cross-connect chip receives the packet, it searches the aggregation multicast group entry according to the aggregation multicast group header to obtain the corresponding aggregation multicast group;

According to the aggregation multicast group, the packet is sent to the corresponding outbound chip.

An embodiment of the present invention further provides a cross-chip multicast forwarding system, including: an aggregation multicast group creation module, a mapping table creation module, an inbound service chip, a cross-connect chip, and an outbound service chip:

The aggregation multicast group creation module is used to: create an aggregation multicast group entry and configure it on the cross-connect chip, the aggregation multicast group entry includes all possible aggregation multicast groups, and each aggregation multicast group is an outgoing multicast group. Direction of chip distribution combination;

The mapping table creation module is used for: obtaining the aggregation multicast group corresponding to the service multicast group according to the chip distribution of each service multicast group, generating a multicast mapping table from the service multicast group to the aggregation multicast group, and configuring it into the service multicast group. chip;

The service chip in the inbound direction is used to: when the service chip in the inbound direction receives the service to be forwarded, look up the multicast mapping table to obtain the corresponding aggregation multicast group, and add the corresponding aggregation group before the service multicast header in the packet. Broadcast group header, sent to the cross chip;

The cross-connect chip is used to: perform multicast forwarding according to the aggregated multicast group header and the aggregated multicast group entry when receiving the message;

The service chip in the outbound direction is used for forwarding the service multicast group after stripping the aggregation multicast group header when receiving the message.

其中，n为所有入方向和出方向的业务芯片的总和。On the basis of the above technical solution, when the aggregation multicast group creation module creates the aggregation multicast group entry, the total number of all possible aggregation multicast groups is:

Among them, n is the sum of all inbound and outbound service chips.

On the basis of the above technical solution, the composition fields of the converged multicast group header include: message type, source chip and converged multicast group; the composition fields of the service multicast header include: service type, service multicast group .

On the basis of the above technical solution, the service chips in the inbound direction are distributed according to the chips corresponding to each service multicast group to obtain the aggregation multicast group corresponding to the service multicast group, including the following steps:

Multicast the service to all chips corresponding to the service;

According to the standard service multicast group join message, the corresponding chip distribution of the service multicast group of each service is obtained, and the aggregation multicast group with the same chip distribution is found from the aggregation multicast group entry as the service multicast group. The corresponding aggregation multicast group.

On the basis of the above technical solution, the cross chip is specifically used for:

When a packet is received, the aggregation multicast group entry is searched according to the aggregation multicast group header, and the corresponding aggregation multicast group is obtained;

According to the aggregation multicast group, the packet is sent to the corresponding outbound chip.

Compared with the prior art, the advantages of the present invention are:

In the case of newly defined convergence multicast group, the present invention uses one convergence multicast group to carry multiple service multicast groups with the same purpose chip distribution, which greatly reduces the design consumption of multicast forwarding on cross chips. When the service chip in the inbound direction receives the service to be forwarded, it searches the multicast mapping table from the service multicast group to the aggregation multicast group to obtain the corresponding aggregation multicast group, and adds the corresponding aggregation multicast group before the service multicast header in the packet. Multicast group header; when the cross-connect chip receives the packet, it performs multicast forwarding according to the aggregated multicast group header; when the outbound service chip receives the packet, it strips the aggregated multicast group header and forwards the service multicast group. . The invention makes the multicast table entry on the cross-connect chip very simple, and the cross-connect chip is not sensitive to service multicasting any information. It only needs to perform multicast forwarding between chips according to the aggregated multicast group header, thereby greatly reducing the hardware consumption of the cross-connect chip. At the same time, the forwarding of multicast services is completed.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic flowchart of a method for multicast forwarding of a cross-connect chip according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the principle of a multicast forwarding method of a cross-chip according to an embodiment of the present invention;

3 is a schematic diagram of a converged multicast group header and a service multicast header according to an embodiment of the present invention;

4 is a schematic diagram of a mapping relationship between an aggregation multicast group and a service multicast group according to an embodiment of the present invention;

FIG. 5 is a flowchart of completing service multicast forwarding by using aggregation multicast according to an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are the Some, but not all, embodiments are disclosed. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Referring to FIG. 1 , the multicast forwarding method of a cross-connect chip according to an embodiment of the present invention includes the following steps:

S1. Create an aggregation multicast group set entry and configure it on each chip of the cross-connect chip, where the aggregation multicast group entry includes all possible aggregation multicast groups, and each aggregation multicast group is a chip distribution combination in the outgoing direction;

S2, according to the chip distribution of each service multicast group, obtain the aggregation multicast group corresponding to the service multicast group, generate a multicast mapping table from the service multicast group to the aggregation multicast group, and configure it to the service chip;

S3. When the service chip in the inbound direction receives the service to be forwarded, it searches the multicast mapping table to obtain the corresponding aggregation multicast group, adds the corresponding aggregation multicast group header before the service multicast header in the packet, and sends it to the cross-connect chip ;

S4. When the cross-connect chip receives the packet, it performs multicast forwarding according to the aggregated multicast group header and the aggregated multicast group entry;

S5. When the service chip in the outbound direction receives the packet, it strips off the aggregation multicast group header and then forwards the service multicast group.

Referring to FIG. 3 , an embodiment of the present invention defines a new converged multicast group header, referred to as a cell header for short, and the constituent fields of the converged multicast group header include: message type, source chip, converged multicast group, etc.; The specific definition of the cell header format of the embodiment is shown in Table 1:

Table 1 cell header format definition table

After the cell header, the multicast service is carried. Referring to FIG. 3 , in the service multicast header of the embodiment of the present invention, the composition fields of the service multicast header include service type, service multicast group, and the like. The specific definition of the service multicast header is shown in Table 2:

Table 2 Service multicast header format definition table

Therefore, the service multicast packets are carried on the aggregation multicast group.

以n＝10为例，

为1023。大大小于动辄几十乃至几百k的业务组播组个数，大大减少了交叉芯片上所需的组播转发表项。The embodiment of the present invention defines an aggregation multicast group for carrying a plurality of service multicast groups with the same purpose chip distribution. Each aggregation multicast group is a chip distribution combination in the outgoing direction. For a distributed system with n service chips, the number of aggregation multicast groups used is:

Taking n=10 as an example,

is 1023. It is much smaller than the number of service multicast groups that can easily reach dozens or even hundreds of k, which greatly reduces the number of multicast forwarding entries required on the cross-connect chip.

Taking n=3 as an example, assuming the chips are A, B, and C, the aggregated multicast group entries are shown in Table 3:

Table 3 Aggregation multicast group entries

Aggregate multicast group index Purpose 0 A 1 B 2 C 3 AB 4 AC 5 BC 6 ABC

All service multicasts are carried and forwarded on these 7 aggregation multicast groups. No matter how many service multicasts there are, it must be a model in these 7 aggregation groups.

Further, find the aggregation multicast group with the same chip distribution from the aggregation multicast group set, and fill in the multicast mapping table from the service multicast on the nfi to the aggregation multicast. The multicast mapping table is shown in Table 4:

Table 4 Multicast mapping table

Aggregate multicast group index Chip distribution Service multicast group number 0 A 1, 3 (the service multicast group only reaches chip A) 1 B 2, 4, 5 (the service multicast group only reaches chip B) 2 C 6, 7, 8 (the service multicast group only reaches chip C) 3 AB 9, 10 (service multicast group only reaches chip AB) 4 AC 11, 12 (the service multicast group only reaches the chip AC) 5 BC 13, 14, 15 (the service multicast group only reaches the chip BC) 6 ABC 16 (service multicast group only reaches chip ABC)

Referring to FIG. 2 , the method for multicast aggregation according to an embodiment of the present invention includes the following steps:

The service chip in the inbound direction completes the cell header encapsulation, and maps the service multicast group to the aggregation multicast group.

The cross chip in the middle completes the forwarding of the aggregation multicast group, and the aggregation multicast group entry is required to be configured on the cross chip. The aggregation multicast group entry includes all possible aggregation multicast groups, that is, the arrangement of all possible outgoing chips. combination.

The chip in the outbound direction completes the stripping of the aggregation multicast group header, and uses the service multicast group to complete the subsequent forwarding of the service multicast.

FIG. 4 is a schematic diagram showing the mapping relationship between the aggregation multicast group and the service multicast group. How to aggregate service multicast to a bearable aggregation multicast group includes the following steps:

创建所有的汇聚组播组表项，这些表项内容包含了所有可能存在的汇聚组播目的芯片的组合。use formula

Create all aggregation multicast group entries, which contain all possible combinations of aggregation multicast destination chips.

Multicast the service to all chips corresponding to the service;

Obtain the corresponding chip distribution of the service multicast group of each service according to the standard service multicast group join message, find the aggregation multicast group with the same chip distribution from the aggregation multicast group set, and fill in the service group on nfi Figure 4 shows the multicast mapping table from broadcast to aggregated multicast.

After the above steps are completed, the forwarding of the message is shown in Figure 5.

First, search the service multicast table on the service chip in the inbound direction to obtain the service multicast group.

Before sending to the cross-connect chip, check the multicast mapping table from the service multicast group to the aggregation multicast group, obtain the aggregation multicast group, and add the aggregation multicast group header.

On the cross-connect chip, the aggregation multicast group entry is searched according to the aggregation multicast group header, and the aggregation multicast group is forwarded.

The packet leaves the cross-connect chip and reaches the outbound service chip, and the aggregation multicast group header is stripped.

The outgoing direction of the chip completes the forwarding of the subsequent service multicast group.

In the embodiment of the present invention, under the condition of newly defined aggregation multicast group, one aggregation multicast group is used to carry multiple service multicast groups with the same destination chip distribution, which greatly reduces the design consumption of multicast forwarding on cross chips. When the inbound service chip receives the service to be forwarded, it searches the multicast mapping table from the service multicast group to the aggregation multicast group to obtain the corresponding aggregation multicast group, and adds the corresponding aggregation group before the service multicast header in the packet. The multicast group header is sent to the corresponding cross-connect chip; when the cross-connect chip receives the packet, it performs multicast forwarding according to the aggregation multicast group header; when the outbound service chip receives the packet, it strips the aggregation multicast group header and performs Forwarding of service multicast groups. It can greatly reduce the hardware consumption of the cross-connect chip and complete the forwarding of multicast services.

Based on the same inventive concept, an embodiment of the present invention further provides a cross-chip multicast forwarding system, including: an aggregation multicast group creation module, a mapping table creation module, an inbound service chip, a cross-connect chip, and an outbound service chip:

The aggregation multicast group creation module is used to: create an aggregation multicast group entry and configure it on the cross-connect chip, the aggregation multicast group entry includes all possible aggregation multicast groups, and each aggregation multicast group is an outgoing multicast group. Direction of chip distribution combination;

The mapping table creation module is used for: obtaining the aggregation multicast group corresponding to the service multicast group according to the chip distribution of each service multicast group, generating a multicast mapping table from the service multicast group to the aggregation multicast group, and configuring it into the service multicast group. chip;

The service chip in the inbound direction is used to: when the service chip in the inbound direction receives the service to be forwarded, look up the multicast mapping table to obtain the corresponding aggregation multicast group, and add the corresponding aggregation group before the service multicast header in the packet. Broadcast group header, sent to the cross chip;

The cross-connect chip is used to: perform multicast forwarding according to the aggregated multicast group header and the aggregated multicast group entry when receiving the message;

The service chip in the outbound direction is used for forwarding the service multicast group after stripping the aggregation multicast group header when receiving the message.

其中，n为所有入方向和出方向的业务芯片的总和。Preferably, when the aggregation multicast group creation module creates the aggregation multicast group entry, the total number of all possible aggregation multicast groups is:

Among them, n is the sum of all inbound and outbound service chips.

Preferably, the composition fields of the convergent multicast group header include: message type, source chip and convergent multicast group; the composition fields of the service multicast header include: service type and service multicast group.

As a preferred implementation of the embodiment of the present invention, the service chips in the inbound direction obtain the aggregation multicast group corresponding to the service multicast group according to the chip distribution corresponding to each service multicast group, including the following steps:

Multicast the service to all chips corresponding to the service;

According to the standard service multicast group join message, the corresponding chip distribution of the service multicast group of each service is obtained, and the aggregation multicast group with the same chip distribution is found from the aggregation multicast group entry as the service multicast group. The corresponding aggregation multicast group.

As a preferred implementation of the embodiment of the present invention, the cross chip is specifically used for:

When a packet is received, the aggregation multicast group entry is searched according to the aggregation multicast group header, and the corresponding aggregation multicast group is obtained;

According to the aggregation multicast group, the packet is sent to the corresponding outbound chip.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, server or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media having computer-usable program code embodied therein, including but not limited to disk storage, optical storage, and the like.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (10)

1. A multicast forwarding method of cross chips is characterized by comprising the following steps:

creating a convergence multicast group table item and configuring the convergence multicast group table item to a cross chip, wherein the convergence multicast group table item comprises all possible convergence multicast groups, and each convergence multicast group is a chip distribution combination in an outgoing direction;

according to the chip distribution of each service multicast group, a convergence multicast group corresponding to the service multicast group is obtained, a multicast mapping table from the service multicast group to the convergence multicast group is generated and configured to a service chip;

when a service chip in the incoming direction receives a service to be forwarded, searching a multicast mapping table to obtain a corresponding convergence multicast group, adding a corresponding convergence multicast group head in front of a service multicast head in a message, and sending the convergence multicast group head to a cross chip;

when receiving the message, the cross chip performs multicast forwarding according to the aggregation multicast group header and the aggregation multicast group table entry;

when the service chip in the outgoing direction receives the message, the head of the convergence multicast group is stripped off, and then the service multicast group is forwarded.

2. The method of claim 1, wherein when creating the aggregate multicast group entry, the total number of all possible aggregate multicast groups is:

wherein n is the sum of all traffic chips in the incoming and outgoing directions.

3. The method of claim 1, wherein the composition field of the aggregated multicast group header comprises: message type, source chip and aggregate multicast group; the composition field of the service multicast header comprises: service type, service multicast group.

4. The method of claim 1, wherein the service chip in the incoming direction obtains the converged multicast group corresponding to the service multicast group according to the chip distribution corresponding to each service multicast group, comprising the following steps:

multicasting the service to all chips corresponding to the service;

and obtaining the corresponding chip distribution of the service multicast group of each service according to the standard service multicast group adding message, and finding the converged multicast group with the same chip distribution from the converged multicast group list item to be used as the converged multicast group corresponding to the service multicast group.

5. The method according to claim 1, wherein when receiving the packet, the cross chip performs multicast forwarding according to the aggregate multicast group header and the aggregate multicast group entry, and specifically includes the following steps:

when the cross chip receives the message, searching the aggregate multicast group list item according to the aggregate multicast group head to obtain the corresponding aggregate multicast group;

and sending the message to a corresponding outgoing direction chip according to the aggregation multicast group.

6. A cross-chip multicast forwarding system, comprising: the system comprises a multicast group convergence establishing module, a mapping table establishing module, an incoming service chip, a cross chip and an outgoing service chip, wherein the multicast group convergence establishing module comprises:

the aggregate multicast group creation module is configured to: creating a convergence multicast group table item and configuring the convergence multicast group table item to a cross chip, wherein the convergence multicast group table item comprises all possible convergence multicast groups, and each convergence multicast group is a chip distribution combination in an outgoing direction;

the mapping table creation module is configured to: according to the chip distribution of each service multicast group, a convergence multicast group corresponding to the service multicast group is obtained, a multicast mapping table from the service multicast group to the convergence multicast group is generated and configured to a service chip;

the business chip in the incoming direction is used for: when a service chip in the incoming direction receives a service to be forwarded, searching a multicast mapping table to obtain a corresponding convergence multicast group, adding a corresponding convergence multicast group head in front of a service multicast head in a message, and sending the convergence multicast group head to a cross chip;

the cross chip is used for: when receiving the message, carrying out multicast forwarding according to the aggregation multicast group header and the aggregation multicast group list item;

the outgoing direction service chip is configured to: when receiving the message, the head of the convergence multicast group is stripped off and then the service multicast group is forwarded.

7. The system of claim 6, wherein the aggregate multicast group creation module, when creating the aggregate multicast group entry, has a total number of all possible aggregate multicast groups of:

wherein n is the sum of all traffic chips in the incoming and outgoing directions.

8. The system of claim 6, wherein the composition field of the aggregated multicast group header comprises: message type, source chip and aggregate multicast group; the composition field of the service multicast header comprises: service type, service multicast group.

9. The system of claim 6, wherein the service chip in the incoming direction obtains the converged multicast group corresponding to the service multicast group according to the chip distribution corresponding to each service multicast group, comprising the following steps:

multicasting the service to all chips corresponding to the service;

and obtaining the corresponding chip distribution of the service multicast group of each service according to the standard service multicast group adding message, and finding the converged multicast group with the same chip distribution from the converged multicast group list item to be used as the converged multicast group corresponding to the service multicast group.

10. The system of claim 6, wherein the crossbar chip is specifically configured to:

when receiving the message, searching a convergent multicast group list item according to the convergent multicast group header to obtain a corresponding convergent multicast group;

and sending the message to a corresponding outgoing direction chip according to the aggregation multicast group.

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