RFC 2642 (rfc2642) - Page 1 of 95

Cabletron's VLS Protocol Specification

Network Working Group                                            L. Kane
Request for Comments: 2642                Cabletron Systems Incorporated
Category: Informational                                      August 1999


                 Cabletron's VLS Protocol Specification

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 (1999).  All Rights Reserved.

Abstract

   The Virtual LAN Link State Protocol (VLSP) is part of the InterSwitch
   Message Protocol (ISMP) which provides interswitch communication
   between switches running Cabletron's SecureFast VLAN (SFVLAN)
   product.  VLSP is used to determine and maintain a fully connected
   mesh topology graph of the switch fabric.  Each switch maintains an
   identical database describing the topology. Call-originating switches
   use the topology database to determine the path over which to route a
   call connection.

   VLSP provides support for equal-cost multipath routing, and
   recalculates routes quickly in the face of topological changes,
   utilizing a minimum of routing protocol traffic.

Table of Contents

    1. Introduction............................................  3
       1.1 Acknowledgments.....................................  3
       1.2 Data Conventions....................................  3
       1.3 ISMP Overview.......................................  4
    2. VLS Protocol Overview...................................  5
       2.1 Definitions of Commonly Used Terms..................  6
       2.2 Differences Between VLSP and OSPF...................  7
           2.2.1 Operation at the Physical Layer...............  8
           2.2.2 All Links Treated as Point-to-Point...........  8
           2.2.3 Routing Path Information......................  9
           2.2.4 Configurable Parameters.......................  9
           2.2.5 Features Not supported........................  9
       2.3 Functional Summary.................................. 10
       2.4 Protocol Packets.................................... 11



Kane                         Informational