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IS-IS Extended Sequence Number TLV

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: RFC Editor <>,
    isis mailing list <>,
    isis chair <>
Subject: Protocol Action: 'IS-IS Extended Sequence number TLV' to Proposed Standard (draft-ietf-isis-extended-sequence-no-tlv-06.txt)

The IESG has approved the following document:
- 'IS-IS Extended Sequence number TLV'
  (draft-ietf-isis-extended-sequence-no-tlv-06.txt) as Proposed Standard

This document is the product of the IS-IS for IP Internets Working Group.

The IESG contact persons are Alvaro Retana, Alia Atlas and Deborah

A URL of this Internet Draft is:

Ballot Text

Technical Summary

This document defines Extended Sequence number TLV to protect Intermediate
System to Intermediate System (IS-IS) PDUs from replay attacks.

Working Group Summary

There was initial resistance by some members of the WG with regard to the need
for the new mechanism. Consensus over the need was achieved, while a technical
objection remained over the inclusion of the extended sequence number TLV in LSP
PDUs as they already contain a sequence number. The new sequence number TLV was
removed from the LSP which dealt with the technical objection.

Document Quality

  No known implementations currently exist. One vendor has expressed interest in
implementing the mechanism for use in DC/TRILL deployments.

Les Ginsberg did multiple in-depth reviews of the document with comments which
were incorporated, and is acknowledged in the document.


  DS: Christian Hopps <>
AD: Alia Atlas <>

RFC Editor Note