Liaison statement
LS to IETF AVT WG, ITU-T SG11 and FG CarCom on Requesting Assitance on the Protocols for draft new Recommendation ITU-T G.MDCSPNE

Submission date 2009-02-18
From ITU-T SG 16 (Simão de Campos)
To IETF AVT WG (Roni Even, Tom Taylor)
Response contact
Technical contact,
Purpose For action
Deadline 2009-05-31 Action Taken
Attachments Draft 8 of G.MDCSPNE "Mechanism for Dynamic Coordination of Voice Enhancement SPNE"
ITU-T Q18 of WP1/16 would like to request your assistance to identify
if there are existing protocols (e.g. RTP packet definitions) that can
be utilized to realize the dynamic coordination mechanism defined in
the draft new Recommendation ITU-T G.MDCSPNE over IP networks.

G.MDCSPNE defines a generic framework and protocol requirements for a
coordination mechanism intended to minimize undesirable interaction of
voice processing functions present on bearer paths of a communication
link, for the purpose of improving overall end-to-end voice quality. 
Voice quality improvement is achieved through the usage of “capability
lists”, exchanged among nodes on the bearer path, to identify the state
of signal processing functions (available/unavailable) over a call
connection.  This information is then used to refer to a common “rule
book” to cause the de-activation of redundant functions, and the
retention of the signal processing functions that are in most
favourable locations for improving voice quality. One important aspect
of G.MDCSPNE is that it allows dynamic coordination of signal
processing functions/devices during a call.  Dynamic coordination is
needed in response to changes in signal processing function
availability due to, for example, call topology changes such as call
transfer or call handover, all within the same call session. The
generic capability list format structure and the rules for
de-activation and retention, based on this state information, have been
finalized in G.MDCSPNE. The scope of G.MDCSPNE, however, does not cover
the definition of protocols for the exchange of capability list
information on the bearer path to realize the coordination mechanism
over IP networks.

ITU-T Q18 of WP1/16 would like to request your assistance in
identifying if there is (are) existing standard specifications that
could serve as a vehicle for exchange of state of availability of voice
processing functions among nodes on a call-path, to satisfy the
requirements for a dynamic coordination mechanism over IP networks as
contained in ITU-T Q18/16 draft G.MDCSPNE. 

ITU-T Q18/16 understands that modification of the generic capability
list format structure in G.MDCSPNE may be needed in order to take
advantage of existing specifications to implement the dynamic
coordination mechanism.  If such should be the case, ITU-T Q18/16 would
appreciate very much if you would provide the modifications needed.  

For information purposes, attached please find the latest version of
G.MDCSPNE for your reference.  G.MDCSPNE is expected to go for consent
at the ITU-T October 2009 SG16 meeting and become an ITU-T standard

-	Draft 8 of G.MDCSPNE “Mechanism for Dynamic Coordination of Voice
Enhancement SPNE”