RFC 6325 · PROPOSED STANDARD · 2011

Routing Bridges : Base Protocol Specification

Overview

RFC 6325, “Routing Bridges : Base Protocol Specification”, is a Proposed Standard document published in July 2011 by R. Perlman, D. Eastlake 3rd, D. Dutt, S. Gai, A. Ghanwani. It has since been updated by RFC 6327, RFC 6439, RFC 7172, RFC 7177, RFC 7179, RFC 7180, RFC 7357, RFC 7455, RFC 7780, RFC 7783, RFC 8139, RFC 8249, RFC 8361, RFC 8377. The canonical text is published by the RFC Editor.

Abstract

Routing Bridges (RBridges) provide optimal pair-wise forwarding without configuration, safe forwarding even during periods of temporary loops, and support for multipathing of both unicast and multicast traffic. They achieve these goals using IS-IS routing and encapsulation of traffic with a header that includes a hop count.

RBridges are compatible with previous IEEE 802.1 customer bridges as well as IPv4 and IPv6 routers and end nodes. They are as invisible to current IP routers as bridges are and, like routers, they terminate the bridge spanning tree protocol.

The design supports VLANs and the optimization of the distribution of multi-destination frames based on VLAN ID and based on IP-derived multicast groups. It also allows unicast forwarding tables at transit RBridges to be sized according to the number of RBridges (rather than the number of end nodes), which allows their forwarding tables to be substantially smaller than in conventional customer bridges. [STANDARDS-TRACK]

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

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 6325 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Other RFCs from 2011

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