RFC 8918 · PROPOSED STANDARD · 2020

Invalid TLV Handling in IS-IS

Overview

RFC 8918, “Invalid TLV Handling in IS-IS”, is a Proposed Standard document published in September 2020 by L. Ginsberg, P. Wells, T. Li, T. Przygienda, S. Hegde. It updates RFC 5305, RFC 6232. The canonical text is published by the RFC Editor.

Abstract

The key to the extensibility of the Intermediate System to Intermediate System (IS-IS) protocol has been the handling of unsupported and/or invalid Type-Length-Value (TLV) tuples. Although there are explicit statements in existing specifications, deployment experience has shown that there are inconsistencies in the behavior when a TLV that is disallowed in a particular Protocol Data Unit (PDU) is received.

This document discusses such cases and makes the correct behavior explicit in order to ensure that interoperability is maximized.

This document updates RFCs 5305 and 6232.

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 8918 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC updates
RFC 5305 RFC 6232
Other RFCs from 2020

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