H.225.0vX => H.323vY

[Paul Long]

Here is something that I finally came to understand on this reflector a few
weeks ago through the kind patience of Jim Toga, Mark Reid, and Joerg Ott. Does
the following need to be documented, or is everyone else comfortable with this
just being understood by all present and future contributors, editors, and
implementors?

Given that

    1. only the version of H.225.0 in use is present in the bit stream (as a
protocol identifier), and

    2. some H.323 semantics may depend on knowing the version of H.323 in use by
the remote endpoint,

then implementing H.323-version-dependent semantics requires that there is
always a one-to-one relationship between H.323 and H.225.0 versions. For
example, an H.323v4 terminal cannot use H.225.0v4 _or_ H.225.0v5 and,
conversely, H.323v2 and H.323v3 terminals cannot both use H.225.0v3.

--
Paul Long___________________________http://www.cmpu.net/public/plong
Smith Micro Software, Inc.__________http://www.smithmicro.com/