RFC 2149 (rfc2149) - Page 1 of 18


Multicast Server Architectures for MARS-based ATM multicasting



Alternative Format: Original Text Document



Network Working Group                                         R. Talpade
Request for Comments: 2149                                      M. Ammar
Category: Informational                  Georgia Institute of Technology
                                                                May 1997


     Multicast Server Architectures for MARS-based ATM multicasting

Status of this Memo

   This memo provides information for the Internet community.  This memo
   does not specify an Internet standard of any kind.  Distribution of
   this memo is unlimited.

Abstract

   A mechanism to support the multicast needs of layer 3 protocols in
   general, and IP in particular, over UNI 3.0/3.1 based ATM networks
   has been described in RFC 2022.  Two basic approaches exist for the
   intra-subnet (intra-cluster) multicasting of IP packets.  One makes
   use of a mesh of point to multipoint VCs (the 'VC Mesh' approach),
   while the other uses a shared point to multipoint tree rooted on a
   Multicast Server (MCS). This memo provides details on the design and
   implementation of an MCS, building on the core mechanisms defined in
   RFC 2022.  It also provides a mechanism for using multiple MCSs per
   group for providing fault tolerance.  This approach can be used with
   RFC 2022 based MARS server and clients, without needing any change in
   their functionality.

1 Introduction

   A solution to the problem of mapping layer 3 multicast service over
   the connection-oriented ATM service provided by UNI 3.0/3.1, has been
   presented in [GA96].  A Multicast Address Resolution Server (MARS) is
   used to maintain a mapping of layer 3 group addresses to ATM
   addresses in that architecture.  It can be considered to be an
   extended analog of the ATM ARP Server introduced in RFC 1577
   ([ML93]).  Hosts in the ATM network use the MARS to resolve layer 3
   multicast addresses into corresponding lists of ATM addresses of
   group members.  Hosts keep the MARS informed when they need to join
   or leave a particular layer 3 group.

   The MARS manages a "cluster" of ATM-attached endpoints.  A "cluster"
   is defined as

   "The set of ATM interfaces choosing to participate in direct ATM
   connections to achieve multicasting of AALSDUs between themselves."




Talpade & Ammar              Informational