ITU/IETF audio call announcement

Bryan Hill bhill at VIDEOSERVER.COM
Thu Mar 25 09:21:39 EST 1999

To IETF Megaco participants, and ITU-T SG16 participants,
As most of you know, both the IETF and the ITU have working groups defining
a device control protocol to be used between a media gateway controller and
a media gateway. In ETSI-Tiphon, this is called the N-interface. Since
November, there have been two different proposals on the table in both
Megaco and in the SG16 group (MGCP and MDCP). There has also been a
compromise proposal - MGCP-modified. MGCP and MDCP differ in many areas, the
main one being the connection model.
A goal shared by many, is to coordinate the Megaco work with the SG16 H.gcp
work, and even to end up with ONE protocol, not two.
At the Monterey ITU meeting, the MGCP/MDCP debate was directed at the
connection model, and at the IETF meeting in Minneapolis last week, these
debates continued. A design team was formed of authors of MGCP, MDCP, and
MGCP-modified. Brian Hill, the H.GCP editor and Glen Freundlich were also
present from SG16. The different connection models were presented,
discussed, dissected... and we ended up inventing brand new terminology to
allow us to explain a new connection model. While the terms context and
termination may not seem clear at first, they do allow us to look at the
problem anew, without the baggage of other proposals getting in the way.
Brian Rosen presented the new connection model to the Megaco WG last Tuesday
(3/16), and to the ITU during the H.gcp audio call this past Tuesday (3/23).
Since then, a group of us has been fleshing out the model, defining
commands, .... People from BOTH SG16 and the IETF have been involved. The
result is the megaco protocol internet-draft that will be out this week, and
sent to both the megaco at <mailto:megaco at>  and
the itu-sg16 at <mailto:itu-sg16 at>  mailing
This internet-draft should be seen as a **working draft** - it has a good
introduction to the new connection model, and provides descriptions of the
commands, but certain sections contain editor notes that document unresolved
issues. And some sections may be left blank. Anyone who would propose a
different way to do something just needs to write it up and send it to the
mailing lists for discussion.
To foster collaboration, we are holding an audio call Monday March 29th at
10am EST, to which all participants in megaco and SG16 are invited. It will
be a chance to air concerns and criticisms of the internet-draft, so that
working group chairs and document editors can get a feel for the degree of
agreement between the two groups.
*****The audio call cannot make any decisions. There will certainly be
people that won't be available for the call.
*****Comments sent to the mailing lists carry equal weight to any
discussions held in the audio call.
*****The minutes of the audio call will be published to the mailing lists.
Ideally, the SG16 group would agree to as much of the internet-draft as they
can, and turn it into the current version of H.GCP. The more we agree on
between the two groups the better.
DATE:   Monday, March 29/99
        TIME: 10amEST till 12pmEST
        NUMBER: 613-763-6338
        PASSCODE: 121212#
        CHAIR: Nancy Greene

problems joining? Call 613-765-CONF (613-765-2663)
90 ports have been booked.
*       because of the potentially large # of people, no tones will be used
to mark people joining or leaving
*       to improve the voice quality, it is important to mute your phone
when you are not speaking - press 63 to mute, and 66 to unmute.

Nancy Greene                          Bryan Hill
ngreene at <mailto:ngreene at>
bhill at <mailto:bhill at>

More information about the sg16-avd mailing list