I-D Action:draft-ietf-bliss-call-completion-10.txt

A New Internet-Draft is available from the on-line Internet-Drafts directories.
This draft is a work item of the Basic Level of Interoperability for SIP Services Working Group of the IETF.

	Title           : Call Completion for Session Initiation Protocol (SIP)
	Author(s)       : D. Worley, et al.
	Filename        : draft-ietf-bliss-call-completion-10.txt
	Pages           : 31
	Date            : 2011-05-06

The call completion features allow the calling user of a failed call
to be notified when the called user becomes available to receive a
call.

For the realization of a basic solution without queuing call-
completion requests, this document references the usage of the the
dialog event package (RFC 4235) that is described as 'automatic
redial' in the SIP Service Examples (RFC 5359).

For the realization of a more comprehensive solution with queuing
call-completion requests, this document introduces an architecture
for implementing these features in the Session Initiation Protocol:
"Call completion" implementations associated with the caller's and
callee's endpoints cooperate to place the caller's request for call
completion into a queue at the callee's endpoint, and, when a
caller's request is ready to be serviced, re-attempt the original,
failed call.

The deployment of a certain SIP call-completion solution is also
dependent on the needed level of interoperability with existing call-
completion solutions in other networks.