RFC 6439 · PROPOSED STANDARD · 2011

Routing Bridges : Appointed Forwarders

Overview

RFC 6439, “Routing Bridges : Appointed Forwarders”, is a Proposed Standard document published in November 2011 by R. Perlman, D. Eastlake, Y. Li, A. Banerjee, F. Hu. It updates RFC 6325. It has since been updated by RFC 7180. It has been obsoleted by RFC 8139 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

The IETF TRILL (TRansparent Interconnection of Lots of Links) protocol provides least cost pair-wise data forwarding without configuration in multi-hop networks with arbitrary topology, safe forwarding even during periods of temporary loops, and support for multipathing of both unicast and multicast traffic. TRILL accomplishes this by using IS-IS (Intermediate System to Intermediate System) link state routing and by encapsulating traffic using a header that includes a hop count. Devices that implement TRILL are called "RBridges" (Routing Bridges).

TRILL supports multi-access LAN (Local Area Network) links that can have multiple end stations and RBridges attached. Where multiple RBridges are attached to a link, native traffic to and from end stations on that link is handled by a subset of those RBridges called "Appointed Forwarders", with the intent that native traffic in each VLAN (Virtual LAN) be handled by at most one RBridge. The purpose of this document is to improve the documentation of the Appointed Forwarder mechanism; thus, it updates RFC 6325. [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 6439 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 8139
This RFC updates
RFC 6325
Updated by
RFC 7180
Other RFCs from 2011

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