Greetings! I am using a Linksys PAP2 (SIP) adapter and trying to connect to an Asterisk server located behind a router doing NAT. UDP ports 5060-5061 and 10000-20000 are forwarded to the internal IP address of the Asterisk server. I even tried putting the server in the DMZ but the results were the same. When I have the Linksys adapter INSIDE my LAN...everything is fine. When I try to connect to Asterisk from outside the LAN, one of two things happens...either the adapter can't register with the SIP server or the adapter does connect but I get one-way audio or no audio at all during phone calls. I have been able to google some information about how SIP is notoriously bad with NAT and firewalls....but there doesn't seem to be an easy fix. Any ideas?