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X.509v3 Transport Layer Security (TLS) Feature Extension

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: RFC Editor <>
Subject: Protocol Action: 'X.509v3 TLS Feature Extension' to Proposed Standard (draft-hallambaker-tlsfeature-10.txt)

The IESG has approved the following document:
- 'X.509v3 TLS Feature Extension'
  (draft-hallambaker-tlsfeature-10.txt) as Proposed Standard

This document has been reviewed in the IETF but is not the product of an
IETF Working Group.

The IESG contact person is Stephen Farrell.

A URL of this Internet Draft is:

Ballot Text

Technical Summary

   The purpose of the TLS feature extension is to prevent downgrade 
   attacks that are not otherwise prevented by the TLS protocol. In 
   particular, the TLS feature extension may be used to mandate support 
   for revocation checking features in the TLS protocol such as OCSP 
   stapling.  Informing clients that an OCSP status response will always
   be stapled permits an immediate failure in the case that the response
   is not stapled. This in turn prevents a denial of service attack that
   might otherwise be possible.

Working Group Summary
   This is not a WG document but has been discussed on the TLS
   list and (so I'm told) has support from browser implementers
   and other implementers.

Document Quality
   The document is short and clear. I'm not clear on current
   implementation status but have been asked a number of
   times about it's status by implementers who want this.
   Sean Turner is the document shepherd. Stephen Farrell  is the
   irresponsible AD.


Please note that up until the -09 version the draft had value 24 for
what is documented as TBD2 in -10 for id-pe-tlsfeature. 

If IANA choose to allocate that value for this that might save some 
trouble for someone later. The value chosen for TBD1 doesn't matter
at all.

RFC Editor Note