RFC 5171 · INFORMATIONAL · 2008

Cisco Systems UniDirectional Link Detection Protocol

Overview

RFC 5171, “Cisco Systems UniDirectional Link Detection Protocol”, is an Informational document published in April 2008 by M. Foschiano. The canonical text is published by the RFC Editor.

Abstract

This document describes a Cisco Systems protocol that can be used to detect and disable unidirectional Ethernet fiber or copper links caused, for instance, by mis-wiring of fiber strands, interface malfunctions, media converters' faults, etc. It operates at Layer 2 in conjunction with IEEE 802.3's existing Layer 1 fault detection mechanisms.

This document explains the protocol objectives and applications, illustrates the specific premises the protocol was based upon, and describes the protocol architecture and related deployment issues to serve as a possible base for future standardization. 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

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