RE: [AVT] Inquiry about RFC 4629 (optional parameters in SDP)

["Even, Roni" <roni.even at polycom.co.il>]

Randell,
Those annexes can be signaled as part of profiles in annex X of H.263. 
Annex X is not proprietary; you can use H263-2000 with profile and
levels.
Specific bodies like 3GPP recommended specific annex X profiles.

There was no request to use them as separate annexes not part of
profiles.

I do not think that anyone will develop a new product using a specific
annex not in the list or not part of a profile. There is H.264 today.

In H.323 we had all the annexes with all the options.
Since in IETF for a standard you must have only parameters that are used
we asked on the list if people are using other annexes which were not in
RFC 4629.

Roni




!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
A consensus means that everyone agrees to say collectively what no one
believes individually
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
> -----Original Message-----
> From: Randell Jesup [mailto:rjesup at wgate.com]
> Sent: Tuesday, September 04, 2007 8:37 PM
> To: Even, Roni
> Cc: Regis Crinon; avt at ietf.org
> Subject: Re: [AVT] Inquiry about RFC 4629 (optional parameters in SDP)
> 
> "Even, Roni" <roni.even at polycom.co.il> writes:
> >The reason for this selection of annexes was based on the ones being
> >used by products in the markets.  There is no need to specify
parameters
> >that are not used.
> 
> Ummm... that just seems totally confused to me.  We won't provide a
way
> to negotiate feature X because no one currently uses feature X - but
if
> you
> can't negotiate it, what use is it to implement it?  (Other than in a
> private, non-RFC-based, non-interoperable setup.)
> 
> It just asks people to either ignore the standard and go totally
> proprietary, extend it ad-hoc and quite possibly incompatibly, or
> cut off any work on using those annexes ever.
> 
> >You can also use annex X based profiles for specifying other
application
> >based profile.
> 
> Which is basically a private, incompatible negotiation.
> 
> 
> I realize this is the way the RFC is; I'm just wondering as to why.
Maybe
> the point was no one had implemented them and the WG believed no would
> would implement them for good reason, and they were effectively
> deprecated.
> 
> --
> Randell Jesup, Worldgate (developers of the Ojo videophone), ex-Amiga
OS
> team
> rjesup at wgate.com
> "The fetters imposed on liberty at home have ever been forged out of
the
> weapons
> provided for defence against real, pretended, or imaginary dangers
from
> abroad."
> 		- James Madison, 4th US president (1751-1836)


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