RFC 3446 (rfc3446) - Page 1 of 7
Anycast Rendevous Point (RP) mechanism using Protocol Independent Multicast (PIM) and Multicast Source Discovery Protocol (MSDP)
Alternative Format: Original Text Document
Network Working Group D. Kim
Request for Comments: 3446 Verio
Category: Informational D. Meyer
H. Kilmer
D. Farinacci
Procket Networks
January 2003
Anycast Rendevous Point (RP) mechanism using
Protocol Independent Multicast (PIM)
and Multicast Source Discovery Protocol (MSDP)
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
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.
1. Introduction
PIM-SM, as defined in RFC 2362, allows for only a single active RP
per group, and as such the decision of optimal RP placement can
become problematic for a multi-regional network deploying PIM-SM.
Anycast RP relaxes an important constraint in PIM-SM, namely, that
there can be only one group to RP mapping can be active at any time.
The single mapping property has several implications, including
traffic concentration, lack of scalable register decapsulation (when
using the shared tree), slow convergence when an active RP fails,
possible sub-optimal forwarding of multicast packets, and distant RP
dependencies. These properties of PIM-SM have been demonstrated in
native continental or inter-continental scale multicast deployments.
As a result, it is clear that ISP backbones require a mechanism that
allows definition of multiple active RPs per group in a single PIM-SM
domain. Further, any such mechanism should also address the issues
addressed above.
Kim, et al. Informational
