We were able to find participants who had implemented the tel:  URL
feature, and it did work for them.  We even tested going from a tel: 
URL to a standard SIP address through a proxy (since the receiver in
this case did not support tel:  URL).  And the multicast register also
(finally) worked, once some misunderstandings were fixed..

                                -- j. kev

IP Bakeoff #5: Advanced Media Testing;
Unofficial summary for one of the two groups, by Brett Tate.
 
It was decided that session hold and retrieval did not need to be
tested.  However the importance of an INVITE without SDP to pull a held
party off of hold was reiterated for its use by third party call
controllers. 
 
Scenario 1) 
 
Allow a re-INVITE to occur which changes the SDP's connection address
and port for an active call.
 
It was soon decided that the scenario could not be initiated by the
players involved.  If I remember correctly, it was decided that putting
the call on hold before the switch invalidated the scenario.
 
The players in the scenario were Cisco, Nuera, 
VegaStream and BroadSoft.
 
Scenario 2) 
 
Allow the media codec to change during call setup.
 
A--B--C
   |
   D
 
A invites C with B acting as a proxy/controller.  
A passes two encoder possibilities within the SDP.
C returns 180 with SDP choice 1.
B cancels the invite to C and invites D.
D returns 180 with SDP choice 2 and answers using 
choice 2.
 
The test was not completed because of lack of time
before players started leaving for the airport.
 
Player A was performed by Cisco and Nuera. 
Player B was BroadSoft.
Players C and D were performed by VegaStream, 
Pingtel, Vovida, and BroadSoft.

Additional scenario idea for next bakeoff:
 
Same as scenario 2 but D passes back 180 
without SDP.  
 
Expected result: ringing switches from remote to local.