RFC 3509 · INFORMATIONAL · 2003

Alternative Implementations of OSPF Area Border Routers

Overview

RFC 3509, “Alternative Implementations of OSPF Area Border Routers”, is an Informational document published in April 2003 by A. Zinin, A. Lindem, D. Yeung. The canonical text is published by the RFC Editor.

Abstract

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 memo provides information for the Internet community.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 3509 is hosted at rfc-editor.org. Available in TXT,HTML.

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