To "prove" that ALG is off, target a host on a public IP with your SIP client, and run a packet capture there. In the "Contact: <sip:someuser@192.168.34.132>;expires=3600" line of the registration ...

Session Initiation Protocol, or SIP, has been hailed as the key to the convergence kingdom, the global signaling standard that will enable all switches, gateways and phones — hard and soft — to talk ...