Skip to main content

Liaison statement
LS on offer/answer procedures

Additional information about IETF liaison relationships is available on the IETF webpage and the Internet Architecture Board liaison webpage.
State Posted
Submitted Date 2008-04-21
From Group 3GPP
From Contact Susanna Kooistra
To Groups mmusic, sipping
To Contacts gonzalo.camarillo@ericsson.com
jf.mule@cablelabs.com
Cc hannu.hietalahti@nokia.com
Purpose For action
Deadline 2008-05-09 Action Taken
Attachments LS on offer/answer procedures
Body
3GPP TSG CT WG1 Meeting #52     C1-081428
Jeju Island, KOREA, 7th – 11th April 2008

Title:  LS on offer/answer procedures
Response to:    -
Release:        -
Work Item:      -

Source: CT1
To:     IETF SIPPING WG
Cc:     IETF MMUSIC WG
Cc:     3GPP/IETF and 3GPP/ITU-T Co-ordinator
Hannu HIETALAHTI (3GPP TSG CT Chair (hannu.hietalahti@nokia.com)
Contact Person:
Name:   Christer HOLMBERG
E-mail Address: christer.holmberg@ericsson.com

Attachments:    None

1. Overall Description:

3GPP CT1 has discussed the "Commit/Rollback of Offer/Answer on Unsuccessful
re-INVITE Transaction" issue in draft-ietf-sipping-sip-offeranswer-06.txt.

A typical example of where subsequent offer/answer transactions may take place
before a final answer to the re-INVITE request is received is when new media
streams are added during an ongoing session, and those media streams require
pre-condition procedures due to network/radio resource reasons.

CT1 has identified the importance of a solution to the matter, in order to
specify and implement interoperable procedures, and to avoid SDP state
misalignments in cases where re-INVITE requests are rejected.

CT1 aims to be able to find a solution to the issue within the 3GPP Release 8
timeframe, which is scheduled to be frozen in December 2008.

2. Actions:
To IETF SIPPING WG
ACTION:         CT1 asks SIPPING to take the importance of the issue into
considerations in their work, and to provide guidance how to proceed on the
matter.

3. Date of Next CT1 Meetings:
TITLE   DATES   LOCATION        CTRY
3GPPCT1#52
7 - 11 Apr 2008         Jeju Island     KR
3GPPCT1#53
5 - 9 May 2008          Cape Town       ZA
3GPPCT1#54
23 - 27 Jun 2008        Zagreb          HR
3GPPCT1#55
18 - 22 Aug 2008        Budapest        HU
3GPPCT1#56
10 - 14 Nov 2008        Shanghai        CN