Network Working Group D. Hamilton Request for Comments: 2641 D. Ruffen Category: Informational Cabletron Systems Incorporated August 1999 Cabletron's VlanHello Protocol Specification Version 4 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 VlanHello protocol is part of the InterSwitch Message Protocol (ISMP) which provides interswitch communication between switches running Cabletron's SecureFast VLAN (SFVLAN) product. Switches use the VlanHello protocol to discover their neighboring switches and establish the topology of the switch fabric. Table of Contents 1. Introduction...................................... 2 1.1 Data Conventions.............................. 2 2. VlanHello Protocol Operational Overview........... 2 2.1 Neighbor Discovery............................ 2 2.2 Port States................................... 3 2.3 Topology Events............................... 5 2.4 Timers........................................ 9 3. InterSwitch Message Protocol...................... 9 3.1 Frame Header.................................. 10 3.2 ISMP Packet Header............................ 11 3.3 ISMP Message Body............................. 12 4. Interswitch Keepalive Message..................... 13 5. Security Considerations........................... 16 6. References........................................ 16 7. Authors' Addresses................................ 16 8. Full Copyright Statement.......................... 17 Hamilton & Ruffen Informational