SIP external calls only work for DISA?

[bcmir]

Hi,
I have a public SIP trunk on OXO R9.1
External calls do not work when on-site, but do work using DISA (same extension in both cases).

The SIP trace shows a 'Rejected, Invite 403' error when attempting call on-site
Although the 'From' header in both cases looks the same.

Anyone have any thoughts why?

[vad]

Wrong management of public/private numbering plan?
Check in trace - what number called (how many digits you receive from provider and compare with dialing plan.

[bcmir]

Public/Private numbering looks ok to me.. I shall check digits again.
It is looking likely that Barracuda firewall (SIP ALG is on by default) is messing with the SIP traffic before it reaches SIP carrier.. since it doesn't show up in my trace.

[bcmir]

If the SIP error 403 is coming from carrier... and the oxo is sending the correct ‘From’ details (as seen in TCP dump). Carrier should be able to tell what the issue is right?

[bcmir]

Looks like system is UDP/TCP switching for outbound SIP, and not using UDP5060, rather TCP 46344 for the INVITE.
Changed Debug Labels/VOIPnwaddr Offset18=01 .. shouldn't use TCP for the Invite now..