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Prefix Unreachable Announcement

Document Type Expired Internet-Draft (individual)
Authors Aijun Wang , Gyan Mishra , Zhibo Hu, Yaqun Xiao
Last updated 2022-04-18 (Latest revision 2021-10-15)
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Expired & archived
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at:


This document describes a mechanism to solve an existing issue with Longest Prefix Match (LPM), that exists where an operator domain is divided into multiple areas or levels where summarization is utilized. This draft addresses a fail-over issue related to a multi areas or levels domain, where a link or node down event occurs resulting in an LPM component prefix being omitted from the FIB resulting in black hole sink of routing and connectivity loss. This draft introduces a new control plane convergence signaling mechanism using a negative prefix called Prefix Unreachable Announcement Mechanism(PUAM), utilized to detect a link or node down event and signal the RIB that the event has occurred to force immediate control plane convergence.


Aijun Wang
Gyan Mishra
Zhibo Hu
Yaqun Xiao

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)