Omission in H.245 v7

Francois Audet audet at NORTELNETWORKS.COM
Wed Mar 28 22:17:24 EST 2001


Actually, this was done on purpose. It was also apparently discussed in the
last meeting
(which I didn't attend).

The way it works with fastStart is that after (or at the same time) as
fastStart is initiated, you'll have to initiate H.245 Terminal capability
negotiation, and
that is where the dynamic payload type will be exchanged. There are
procedures in
H.323v4 that allows you to do terminal capability negotiation in parrallel
with fastStart.

The whole idea is to stop adding things to fastStart.

-----Original Message-----
From: Rajesh Kumar [mailto:rkumar at CISCO.COM]
Sent: Wednesday, March 28, 2001 18:56
To: ITU-SG16 at MAILBAG.INTEL.COM
Subject: Omission in H.245 v7


Dear ITU SG16 team,
I just came across what I believe is an unintended omission in H.245 v7.

Although you have added support for rfc2833 to the 'terminal capability
set' command, you have not included it as one of the CHOICEs for the
dataType object in the Open Logical Channel command. The upshot is that you
cannot dynamically assign a payload type to rfc2833 telephone events in the
'fast connect' scenario where the 'terminal capability set' command is not
used. For all practical purposes, this means that you either statically
provision the rfc2833 capability, which the IETF has decried, or you do not
use Fast Connect when you support telephone events.

All indications are that this is a minor, unintended omission on the part
of SG16: nobody has discovered it as yet. It can be fixed easily. The Open
Logical Channel dataType object points to the capability objects anyway,
and there is no reason to omit AudioTelephonyEventCapability as an instance
of the dataType object.

How should we go about fixing this - H.245 is still in draft, although
there is preliminary approval of it?


Thanks.

Rajesh
-------------------------------------
Dr. Rajesh Kumar, Principal Engineer
Cisco Voice Technology Center
Tel: 408-527-0811, Fax: 408-853-1101
Epage: mailto:rkumar at epage.cisco.com
-------------------------------------

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
For help on this mail list, send "HELP ITU-SG16" in a message to
listserv at mailbag.intel.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.packetizer.com/pipermail/sg16-avd/attachments/20010328/698d224b/attachment-0004.html>


More information about the sg16-avd mailing list