asterisk users - May 2006 - Cisco 2851 as T1 Gateway and Asterisk

I have configured an asterisk server and Cisco router to provide T1 access out
to the PSTN.

I have a real simple dial plan as all incoming calls from the PSTN just get
passed to Asterisk and all outgoing calls from Asterisk just get passed to the
PSTN.

All is working for outbound calling.  And inbound calling is only working if I
have allowguest=no in the sip.conf.

If I do not allow guest connections to the Asterisk server inbound calls fail
with the following message;

chan_sip.c:10319 handle_request_invite: Failed to authenticate user
<sip:xxxxxxxxxx@10.1.2.181>;tag=1568360-2675

Where xxxxxxxxxx is calling number?  When I allowguest all works like it
should.

I think I must be missing something in term of authenticating the router to the
Asterisk server.

Below is my dial-peers, sip-ua on my cisco router and my sip.conf settings.


**** from Cisco - 2 PRI ports in ****

dial-peer voice 101 pots
 destination-pattern .T
 direct-inward-dial
 port 0/0/0:23
 forward-digits all
!         
dial-peer voice 102 pots
 destination-pattern .T
 direct-inward-dial
 port 0/0/1:23
 forward-digits all
!
dial-peer voice 201 voip
 destination-pattern .T
 voice-class codec 1
 session protocol sipv2
 session target ipv4:10.1.2.181:5060
 session transport udp
 dtmf-relay rtp-nte
 no vad
!
sip-ua 
 retry invite 3
 retry response 3
 retry bye 3
 retry cancel 3
 timers expires 300000
 sip-server ipv4:10.1.2.181:5060


**** from asterisk sip.conf ****

[general]
..
allowguest=no
..

[CiscoT1Gateway]
type=friend
host=10.1.221.5
context=Incoming
dtmfmode=rfc2833
disallow=all
allow=ulaw
allow=alaw
qualify=yes
canreinvite=yes







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