RFC 1586 (rfc1586) - Page 1 of 6
Guidelines for Running OSPF Over Frame Relay Networks
Alternative Format: Original Text Document
Network Working Group O. deSouza
Request for Comments: 1586 M. Rodrigues
Category: Informational AT&T Bell Laboratories
March 1994
Guidelines for Running OSPF
Over Frame Relay Networks
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
This memo specifies guidelines for implementors and users of the Open
Shortest Path First (OSPF) routing protocol to bring about
improvements in how the protocol runs over frame relay networks. We
show how to configure frame relay interfaces in a way that obviates
the "full-mesh" connectivity required by current OSPF
implementations. This allows for simpler, more economic network
designs. These guidelines do not require any protocol changes; they
only provide recommendations for how OSPF should be implemented and
configured to use frame relay networks efficiently.
Acknowledgements
This memo is the result of work done in the OSPF Working Group of the
IETF. Comments and contributions from several sources, especially
Fred Baker of ACC, John Moy of Proteon, and Bala Rajagopalan of AT&T
Bell Laboratories are included in this work.
1. Introduction
A frame relay (FR) network provides virtual circuits (VCs) to
interconnect attached devices. Each VC is uniquely identified at each
FR interface by a Data Link Connection Identifier (DLCI). RFC 1294
specifies the encapsulation of multiprotocol traffic over FR [1].
The devices on a FR network may either be fully interconnected with a
"mesh" of VCs, or partially interconnected. OSPF characterizes FR
networks as non-broadcast multiple access (NBMA) because they can
support more than two attached routers, but do not have a broadcast
capability [2]. Under the NBMA model, the physical FR interface on a
router corresponds to a single OSPF interface through which the
router is connected to one or more neighbors on the FR network; all
the neighboring routers must also be directly connected to each other
deSouza & Rodrigues