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Concluded WG Basic Level of Interoperability for SIP Services (bliss)

Note: The data for concluded WGs is occasionally incorrect.

WG Name Basic Level of Interoperability for SIP Services
Acronym bliss
Area Real-time Applications and Infrastructure Area (rai)
State Concluded
Charter charter-ietf-bliss-05 Approved
Document dependencies
Additional resources Issue tracker, Wiki
Personnel Chair Shida Schubert
Area Director Robert Sparks
Tech Advisor Jonathan Rosenberg
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Final Charter for Working Group

The BLISS working group is rechartered to adjust
its scope to reflect changes in working group interest
and RAI processes since its original chartering.

BLISS was chartered prior to the creation of DISPATCH.
The charter called for the WG to document how to realize
four initial building blocks in an interoperable way with
existing standards, and to describe the use of those building
blocks to implement specific call features. Any extensions
to the protocols beyond the creation of event packages or
the addition of SIP URI parameters was set out of scope
for this working group.

Working group interest in all but two of those building
blocks has diminished. The current drafts on those two
propose extensions that under the original charter would
need to be developed in other working groups. Given the
update to the SIP change process (RFC5727) and the
subsequent restructuring of the RAI area, these constraints
are being revised as detailed below.

The BLISS working group shall be closed after completing
the following two proposed standards:
- call completion with queuing as proposed in
- shared appearances as proposed in

The goal to produce a problem statement and a
common template for describing primitives is abandoned.

The group will continue to work within the constraints of
the creation of event packages and SIP URI parameters, with
the addition of the ability to

  • exercise the already standardized extension points of
    SIP header fields. Currently, the documents propose to
    extend the SIP Alert-Info header field (RFC3261) to carry
    an appearance identifier, and the SIP Call-Info header
    field (RFC3261) to carry a call completion indicator.

  • extend the SIP Dialog event package (RFC4235) to carry
    appearance related state,

The working group will coordinate review of those extensions
with the SIPCORE working group.

Describing the security properties (particularly any privacy
considerations) of these deliverables remains of special

Upon completion of these two work items, the working group
will conclude. Future proposals should be directed to the
DISPATCH working group.


Date Milestone Associated documents
Sep 2012 Bliss concludes
Jul 2012 Submit Call Completion to the IESG for publication as Proposed Standard
Mar 2012 Submit Shared Appearances to the IESG for publication as Proposed Standard