asterisk users - Jun 2009 - Restricting domains with SIP Trunking

Hello, all.  We have successfully connected our new Asterisk 1.6.1.1 PBX
to Vitelity's network and have been very happy with them thus far.
However, we'd like to use domains in our sip.conf to facilitate routing
in our multi-tenant environment.  We also like to set
allowexternaldomains=no for security.  However, this breaks our inbound
PSTN calling from Vitelity.

Is it possible to use allowexternaldomains=no with VoIP carriers? We
tried setting fromdomain=<a local domain>.  We tried defining a Vitelity
domain based upon both vitelity.net and IP address (although I'm really
hesitant to do that in case it changes).  None of it worked.  I have
explicitly defined my localhost by name and IP address although I don't
think that matters for this problem.

How are others doing this? Thanks - John
-- 
John A. Sullivan III
Open Source Development Corporation
+1 207-985-7880
jsullivan at opensourcedevel.com

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