How about this scenario? Is it possible Asterisk to be installed on a NAT router/gateway box (using netfilter, which is actually port restricted cone NAT! )?
I have successfully installed Asterisk on such gateway and also I setup a softphone on the PC which is behind this NAT in the private LAN. The softphone can register to the asterisk without any problems, but it’s not possible to dial out and to receive any incoming calls as well?! For instance if I try to dial a FWD number using the softphone behind the NAT nothing happens, it’s the same with the incoming calls.
I have played with all NAT related settings in the SIP.conf also I opened udp 5060 on my external interface on the NAT box, but still no success. Also I have seen the SIP mesages using SIP debug options in the Asterisk CLI and the only suspecious thing I saw was the “NAT transmiting” and then I got an 404 error.
I’ll appreciate if someone can give me an idea of what’s going on and whether this scenario of Asterisk installation is possible or not.
Thanks in advance!