使用CR-LDP协议实现组播的研究

Realization of Multicast Using CR-LDP

扩展RSVP从设计之初就考虑了支持组播技术,而CR-LDP没有提供支持组播的机制。虽然已经有了关于MPLS组播的规范草案,但其中只是对组播路由协议的选择以及与组播的各种可选项的关系进行了讨论,并没有提出如何使用CR-LDP实现组播机制。通过对CR-LDP的消息进行扩展,可以在MPLS网络中建立组播路径和LSP,从而实现具有流量工程特征的组播路径。该文对如何使用CR-LDP实现组播进行了详细的论述。

Compared with RSVP, CR-LDP dose not provide support for multicast, yet RSVP provide support for multicast at the beginning of design. Although there have been drafts of standardization about MPLS multicast architecture, it dose not describe how to realize multicast with CR-LDP in MPLS network and just discuss the choice of multicast route protocol and the relation between multicast and optional parts of LDP. A new method is proposed to build a shared multicast distribution tree centered at a rendezvous point using CR-LDP message（extensions）, This paper discusses how to realize multicast with CR-LDP in MPLS network.