Subject: RE: SIP

From: Francois Menard Distribution List Management Account <[email-masked]>
Date: Fri, 22 Jan 1999 07:54:18 -0500

> Let's see now, a firewall with proxies that only let through known
protocols and check with the gatekeeper for H.323 admission. Scarey!

No no, 

The whole H.323 hypothesis is that you can control the end-points and force
them to use a given gatekeeper.  This is as long as the end-users are not
capable of figuring out how to change the config of the end-points to bypass
the GK...

I've always maintained that on the Internet, it is not because you route a
call that you can bill for it.

In H.323 on the Internet, you can bill for:

1. QOS for all apps at the same time on the host
2. PSTN access through a metered H.323 PSTN gateway
3. Apps on GKs. (i.e. there is some value in a GK translating a phone number
to a dynamic IP address)

So I do not believe that basic H.RAS stuff actually makes it possible to
derive a bill.  GK-routed call models are a billing mechanism, not a
bandwidth preserving thing.  So IMHO, by definition, it is only possible as
long as you can force the end-points to collaborate.

Same for a SIP server-routed call models too.  But then, SIP makes no
assumption about the rationality of SIP-server call routed models to create
illusions about the real problems of IP telephony.

-=Francois=-

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