Multicast Source Discovery Protocol

Abstract: The use of a packet's Time to Live (TTL) (IPv4) or Hop Limit (IPv6) to protect a protocol stack from CPU-utilization based attacks has been proposed in many settings (see for example, RFC 2461). This document generalizes these techniques for use by other protocols such as BGP (RFC 1771), Multicast Source Discovery Protocol (MSDP), Bidirectional Forwarding Detection, and Label Distribution Protocol (LDP) (RFC 3036). While the Generalized TTL Security Mechanism (GTSM) is most effective in protecting directly connected protocol peers, it can also provide a lower level of protection to multi-hop sessions. GTSM is not directly applicable to protocols employing flooding mechanisms (e.g., multicast), and use of multi-hop GTSM should be considered on a case-by-case basis.

Abstract: This document describes a mechanism to allow for an arbitrary number of Rendevous Points (RPs) per group in a single shared-tree Protocol Independent Multicast-Sparse Mode (PIM-SM) domain.

Abstract: A Multicast Source Discovery Protocol (MSDP) speaker can associate a “key” with a set of one or more source address/group address pairs within a Source Active (SA) message and send the SA message to a MSDP peer. Initially, the MSDP speaker sends both the key and the source address/group address pairs associated with that key. Subsequently, the MSDP speaker can simply resend the key, without also sending all of the associated source address/group address pairs, in order to refresh the SA information at the peer. Additionally, several keys can be sent in a single message.

Abstract: This specification allows Anycast-RP (Rendezvous Point) to be used inside a domain that runs Protocol Independent Multicast (PIM) only. Other multicast protocols (such as Multicast Source Discovery Protocol (MSDP), which has been used traditionally to solve this problem) are not required to support Anycast-RP. [STANDARDS-TRACK]