Subject: [AVT] draft-basso-avt-videoconreq-00: H.245 and Section 7.8

From: "Eric Burger" <[email-masked]>
Date: Thu, 23 Oct 2003 23:45:08 -0400

I am concerned about the potential direction the requirement stated in section 7.8 may bring us.  Here is the text:

  7.8 Interoperability with other protocols 
    
      The codec control transport protocol MUST allow inter-operability 
      with the most commonly deployed IP-based video communication 
      protocols, such as H.323, H.324 and H.324M.

What does this mean.  On one level, it sounds straightforward.  If I have a video system, and you have a video system, then we should be able to communicate.  In fact, given a lexicon, how could one NOT create mappings between different grammars for that lexicon?  In that sense, this is a non-requirement and should be removed.

However, at another level, and taken in conjunction with the statement of section 6.3 (protocol duplication), it is hideous.  Direct interoperability means that we should take the common signaling denominator for these three protocols, namely H.245.

H.245 sound innocent enough, as it is independent of H.323 and H.324.  However, when one looks closer, we find a lot of overlap between H.245 and SDP and (please look at the protocol) SIP.

I would offer that if H.245, or something like H.245, is what is being thought of for this requirement, then there is no reason for this draft.  Use H.323/H.324/H.324m/H.320 and Be Happy.

If there is any requirement that should be in the document, it is an emphasis on Section 6.2.  I would offer that the call control and content negotiation capabilities of H.245 "break" SIP and SDP (or conversely, would not interoperate in the ITU direction).  Since this is the IETF, I really only care about not breaking IETF protocols.  You can break the broken protocols to your hearts content :-)

_______________________________________________
Audio/Video Transport Working Group
[email-masked]
https://www1.ietf.org/mailman/listinfo/avt

---

From: Henry Sinnreich <[email-masked]>
Date: Fri, 24 Oct 2003 05:43:30 -0500

I agree that the requirement is pure non-sense.

There are gateways between IETF SIP based systems and legacy
implementations.

Thanks, Henry

Henry Sinnreich

MCI
400 International Parkway
Richardson, Texas 75081
USA

Have you disconnected the PBX?

-----Original Message-----
From: Eric Burger [mailto:[email-masked]] 
Sent: Thursday, October 23, 2003 10:45 PM
To: [email-masked]
Subject: draft-basso-avt-videoconreq-00: H.245 and Section 7.8

I am concerned about the potential direction the requirement stated in
section 7.8 may bring us.  Here is the text:

What does this mean.  On one level, it sounds straightforward.  If I have a
video system, and you have a video system, then we should be able to
communicate.  In fact, given a lexicon, how could one NOT create mappings
between different grammars for that lexicon?  In that sense, this is a
non-requirement and should be removed.

However, at another level, and taken in conjunction with the statement of
section 6.3 (protocol duplication), it is hideous.  Direct interoperability
means that we should take the common signaling denominator for these three
protocols, namely H.245.

H.245 sound innocent enough, as it is independent of H.323 and H.324.
However, when one looks closer, we find a lot of overlap between H.245 and
SDP and (please look at the protocol) SIP.

I would offer that if H.245, or something like H.245, is what is being
thought of for this requirement, then there is no reason for this draft.
Use H.323/H.324/H.324m/H.320 and Be Happy.

If there is any requirement that should be in the document, it is an
emphasis on Section 6.2.  I would offer that the call control and content
negotiation capabilities of H.245 "break" SIP and SDP (or conversely, would
not interoperate in the ITU direction).  Since this is the IETF, I really
only care about not breaking IETF protocols.  You can break the broken
protocols to your hearts content :-)