H.323 Annex E optional?

[Paul E. Jones]

Manoj,

No, direct call routing is still possible.  Yes, one would have problems if
the GK allowed direct call routing to unknown endpoints and forced its
endpoints to always use Annex E-- that would not be a wise thing to do.

In some environments, it is possible that every endpoint will be Annex E
capable and the operators may want to force that mode of operation.  In some
cases, there may be a mixture of Annex E-capable and non-Annex E-capable
devices.  In that case, it would be unwise to force endpoints to use Annex
E, unless every call will be routed.  However, to maximize the usage of
Annex E where desired in a direct call model, the GK can learn from the LRQ
whether a remote endpoint supports Annex E and can tell the endpoint whether
to use or not to use Annex E in each ACF.

Paul

----- Original Message -----
From: Manoj Paul <mpaul at TRILLIUM.COM>
To: <ITU-SG16 at mailbag.cps.intel.com>
Sent: Friday, July 30, 1999 2:19 PM
Subject: Re: H.323 Annex E optional?


> > Paul,
> >
> > Okay, but what if the EP does not indicate that it has this capability?
> > 7.9.2/H.225.0v3 currently says that the EP _shall_ use an unreliable
channel
> > if in receipt of an RCF with useAnnexECallSignalling set to TRUE.
Period.
> > Regardless of whether the endpoint indicated the capability in its RRQ.
The
> > following would eliminate the ambiguity and possible misunderstanding:
> >
> > 7.9.2/H.225.0v3: "useAnnexECallSignalling - If TRUE and
> > supportsAnnexECallSignalling was set to TRUE in the RRQ to which this
> > message is in response, the endpoint receiving this message shall use
call
> > signaling exclusively on an unreliable transport channel as described in
> > H.323 Annex E when placing calls."
>
>    Doesn't it mean that Gk can not adopt direct call routed model between
>    endpoints. Consider when the remote endpoint is not Annex E Compliant.
>    Now Ep1 sends call signalling messages *only* over
>    UDP (after receiving useAnnexECallSignalling = TRUE in RCF). This
direct
>    routed call will not go through as Ep2 is not Annex E compliant.
>
>    Should Ep1 look into the callModel in ACF to figure out if it is
>    Gk/direct routed call. If Gk routed and useAnnexECallSig = TRUE,
>    do only UDP call signalling, and if direct routed, use Annex E
>    Mixed TCP and UDP procedures ?
>
>
>  -M.Paul.
>