Method for implementing multicast forwarding tree based on multicast source discovering protocol

Abstract

The present invention discloses multicastings transmit tree method implemented by multicasting source discover agreement, which includes: local MSDP edge router transmits activity source enquiring message to the field RP which knows local multicasting tree existing valid activity source, activity source enquire answering message is constructed, and sent to local MSDP edge router; the MSDP edge router sends the reply message with valid activity source to far-end MSDP partner through SA message; the MSDP partner stores the received SA message, local existing corresponding multicasting group, and sends message of adding multicasting group to far-end activity source, then activity source log-on message is constructed, and is sent to local RP; the local RP transmits activity source register stop message to the partner. The present invention creates multicasting transmit tree quickly at MSDP edge router situated at downstream of RP, can execute across field multicasting flow capacity transmitting validly, and has flexible and simple group net.

Description

technical field [0001] The invention relates to the field of IP network multicast, in particular to a method for optimizing MSDP (Multicast Source Discover Protocol, Multicast Source Discovery Protocol) to realize multicast forwarding tree. Background technique [0002] At present, when establishing cross-domain multicast networking applications, a solution combining PIM-SM (protocolindependent-multicast-sparse mode) / MBGP (Multi-Protocol Border Network Management Protocol) / MSDP is often used. The MSDP describes the interconnection mechanism of multiple PIM-SM domains, which can enable RPs (rendezvous point, rendezvous point) in different PIM-SM domains to share activity source information. Each RP knows the receivers in this domain. When RPs know the active source information of the remote domain, they can pass the information to the receivers in this domain. In this way, the multicast data packets can be forwarded between PIM domains. That is, a cross-domain multicast forw...

AI Technical Summary

Problems solved by technology

[0005] It can be seen from the above description that when performing cross-domain multicast network multicast, the essence is to deploy RP and MSDP on the same device, which is not only not flexible enough, but also greatly increases the complexity of the network.

[0006] To sum up, in the prior art, in order to overcome when the RP and the MSDP edge router are configured on different devices, especially when the MSDP edge router is located downstream of the RP (that is, on the path from the RP to the last-hop multicast router) ), the networking is not flexible enough and the networking is complex. There is an urgent need for a mechanism to ensure that the RP and the MSDP edge router can not only know each other's activity source information, but also quickly create a specific multicast source in the domain. / group pair, for multicast stream forwarding

Images