Problem Statement and Requirements for Transporting User to User Call Control Information in SIP

Document Type Replaced Internet-Draft (individual)
Last updated 2011-11-22 (latest revision 2010-09-15)
Replaced by draft-ietf-cuss-sip-uui-reqs
Stream (None)
Intended RFC status (None)
Expired & archived
pdf htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Replaced by draft-ietf-cuss-sip-uui-reqs
Telechat date
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


This document introduces the transport of call control related User to User Information (UUI) in the Session Initiation Protocol (SIP), and develops several requirements for a new SIP mechanism. Some SIP sessions are established by or related to a non-SIP application. This application may have information that needs to be transported between the SIP User Agents during session establishment. A common example in another protocol is the ITU-T Q.931 User to User Information Service. As networks move to SIP it is important that applications requiring this data can continue to function in SIP networks as well as the ability to interwork with this ISDN service for end-to-end transparency. This document discusses requirements and approaches. This extension will also be used for native SIP endpoints implementing similar services and interworking with ISDN services. Example use cases include an exchange between two user agents, retargeting by a proxy, and redirection. An example application is an Automatic Call Distributor (ACD) in a contact center.


Alan Johnston (
Joanne McMillen (
Laura Liess (

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)