TCP User Timeout Option
RFC 5482

Approval announcement
Draft of message to be sent after approval:

From: The IESG <>
To: IETF-Announce <>
Cc: Internet Architecture Board <>,
    RFC Editor <>, 
    tcpm mailing list <>, 
    tcpm chair <>
Subject: Protocol Action: 'TCP User Timeout Option' to Proposed 

The IESG has approved the following document:

- 'TCP User Timeout Option '
   <draft-ietf-tcpm-tcp-uto-11.txt> as a Proposed Standard

This document is the product of the TCP Maintenance and Minor Extensions 
Working Group. 

The IESG contact persons are Magnus Westerlund and Lars Eggert.

A URL of this Internet-Draft is:

Technical Summary:

    This document calls for an option to all TCP endpoints to
    request peers to set the user-timeout to a particular value.
    The motivation behind this option is hosts that understand that
    they will be unavailable for a lengthy period of time and can
    thus inform their peer of this phenomenon such that the peer can
    prevent the normal connection aborting procedures from reaping
    the connection.  The information is advisory and therefore the
    peer is still able to abort the connection (e.g., in times of
    resource contention).

Working Group Summary

    Given that the information exchanged is advisory, the TCPM WG
    has consensus that this option is perfectly reasonable.

Document Quality

    The document was reviewed for quality by a large number of TCPM
    WG members.


   Responsible AD was Magnus Westerlund. WG shepherd is Wesley Eddy. 

Note to RFC Editor

New paragraph as the second paragraph in section 4.1:

Implementations may want to exchange UTO options on the very first data
segments after the three-way handshake to determine if such a middlebox
exists on the path. When segments carrying UTO options are persistently
lost, an implementation should turn off the use of UTO for the connection.
When the connection itself is reset, an implementation may be able to
transparently re-establish another connection instance that does not use
UTO before any application data has been successfully exchanged.