Hi List.

Please, I need some help with strict routing problem.

Incoming calls are canceled at 30 secs from an origination provider.

The problem seems to be a bad ACK sent from the origination, because it performs strict routing instead of loose routing. The ACK goes from originator to my SER server, then it must go to a Nat Traversal server and finally to the UA client, but instead of that the ACK tries to go directly from SER to the UA in its local address 192.168.1.109, skipping the Nat Traversal server. The UA sends a BYE to the call because it never receives this ACK.

I use another origination provider in the same scenario without problems. This other origination uses loose routing, and ACK messages go in the right path: origination -> SER -> Nat traversal -> UA.

How can I resolve this strict routing problem?

Thanks in advance, Rosa.