Cisco 7960 Unable to register from external network

I just installed Freepbx 5.2.11 with Asterisk 1.8.27. I also installed several Cisco 7960 Phones on my internal network and they are working fine. I just cannot register these phones from a remote offce. I am using P003-8-12-00 and nated from the external IP to the internal. Pointed the TFTP server to the public network but the phone does not register. Is there anyone with a previos experiences? I have days reading adn looking for information but Ihaven been able to find. Is ther somethign special to consider for these phones?? I have th eones on the local netowrk working without problems.


These phones are not NAT friendly. Invest $100 in a pair of VPN routers or us phones outside the network that work perfect with NAT like the Polycom or Cisco/Linksys SPA series.

Can you please recommend any brand or so?? I have Cisco routers and Firewalls in our network.

Any Cisco router and firewall can create a VPN.

Just build the tunnel back to the network the FreePBX server is in. Add the remote network to FreePBX SIP Settings /localnets and you will never have trouble again.