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Alternative Implementations of OSPF Area Border Routers

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 3509.
Authors Derek M. Yeung , Acee Lindem , Alex D. Zinin
Last updated 2015-10-14 (Latest revision 2002-10-24)
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status Informational
Additional resources Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state Became RFC 3509 (Informational)
Action Holders
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD Bill Fenner (ˢˣˠ)
IESG note
Send notices to <>, <>
A new Request for Comments is now available in online RFC libraries.

        RFC 3509

        Title:      Alternative Implementations of OSPF Area Border
        Author(s):  A. Zinin, A. Lindem, D. Yeung
        Status:     Informational
        Date:       April 2003
        Pages:      12
        Characters: 24326
        Updates/Obsoletes/SeeAlso:  None

        I-D Tag:    draft-ietf-ospf-abr-alt-05.txt


Open Shortest Path First (OSPF) is a link-state intra-domain routing
protocol used for routing in IP networks.  Though the definition of
the Area Border Router (ABR) in the OSPF specification does not
require a router with multiple attached areas to have a backbone
connection, it is actually necessary to provide successful routing to
the inter-area and external destinations.  If this requirement is not
met, all traffic destined for the areas not connected to such an ABR
or out of the OSPF domain, is dropped.  This document describes
alternative ABR behaviors implemented in Cisco and IBM routers.

This document is a product of the Open Shortest Path First IGP Working
Group of the IETF.

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