1. July 2007 (IETF 69)IETF - SIPPING1 Replace Instant Message in SIP draft-ren-sipping-replace-instant-message-00 Da Qi Ren, Qian Sun and Linyi Tian IETF 69, Chicago

2. July 2007 (IETF 69)IETF - SIPPING2 Requirements A message sender wants to replace an instant message they previously sent due to the original message containing errors, needing an update, or simply no longer being required.

3. July 2007 (IETF 69)IETF - SIPPING3 Applicability An Instant Message (IM) can be deferred and stored somewhere in the network – Many young people prefer to use IM, and send instant messages to friends when their friends are offline, out of coverage, etc. In addition, people in different time zones are no on line at the same time. – Similar to the case of email, it is practical to recall or replace an instant message when it is stored in the relay.

4. July 2007 (IETF 69)IETF - SIPPING4 Question: Can we simply send another message? – The original message cause confusion. – The receiver simply desires a correct or updated message.

5. July 2007 (IETF 69)IETF - SIPPING5 Alice Alice sends Bob a MESSAGE to let him know about a meeting time and place. Shortly after sending that, the meeting is rescheduled to a new place and time. Alice sends a new MESSAGE to replace the previous one. Example Bob Bob is offline when Alice sends the first and second (replaced) MESSAGE. When Bob returns online, he reads the second MESSAGE. Or if Bob first reads the previous message, the client may prompt that the message has been replaced. In this case Bob has the correct time and place for the meeting.

6. July 2007 (IETF 69)IETF - SIPPING6 Replace/Recall Examples in Other SDOs The replace/recall feature has been supported by SMS, MMS and Email. See examples in the following slides.

7. July 2007 (IETF 69)IETF - SIPPING7 Reference I: SMS 3GPP Technical realization of the Short Message Service (SMS) – TS 23.040 V6.7.0 (2006-03) Defined in MS capabilities – 7.1 The MS, when equipped for SMS, should be capable of: notifying the SC when a short message is intended to replace a short message the MS has previously submitted to the same destination address. – 9.2.3.9 TP-Protocol-Identifier (TP-PID): Replace Short Message Type code – 9.2.3.19 TP-Command-Type (TP-CT) : 00000010 Delete previously submitted Short Message

8. July 2007 (IETF 69)IETF - SIPPING8 Reference II : MMS The 3rd Generation Partnership Project (3GPP) – 3GPP TS 22.140 V6.7.0 (2005-03) Replacing MM – The MMS shall be able to support a request by a VASP to replace a previously sent MM from the VASP with a second newer MM. Cancellation of MM – The MMS shall be able to support a request by a VASP to delete a MM that had previously been sent from the VASP but not yet delivered to the terminal.

9. July 2007 (IETF 69)IETF - SIPPING9 Reference III: Email Replace/recall features in email RFC4021: – 2.1.46. Header Field: Supersedes Description: Reference message to be replaced Status: standards-track

10. July 2007 (IETF 69)IETF - SIPPING10 Protocol Problems # 1: Conveying replace/recall: – Should a SIP header field be used to convey replace/recall in a SIP MESSAGE request? – Should it be conveyed within the CPIM body? # 2: Identifying the previous SIP instant message to be replaced: – The counterpart mechanism for email is the Message- ID. What should be used for SIP MESSAGE request?

11. July 2007 (IETF 69)IETF - SIPPING11 Next Step #1: Soliciting feedback and comments; #2: Working group item?

12. July 2007 (IETF 69)IETF - SIPPING12 Thank You! Merci!