Freevoice PBX systems can support remote VoIP phones connected over the public internet. To connect remote phones to your system the following ports must be opened or forwarded to the Freevoice PBX server.

SIP Phones Require Ports: 5060 and 10,000 through 20,000 UDP
IAX2 Phones Require Port: 4569 UDP

Remote SIP phones also require that the external (public) ip address of the server/router be added to the sip_nat.conf file, follow the instructions below to update this file. 

Editing the sip_nat.conf file to allow remote/external VoIP phones

1. Log into your Freevoice PBX admin page.
2. Mouse over PBX and click File Editor.
3. Scroll down to near the bottom of the page and click sip_nat.conf.
   
4. Insert two entries as shown below, make sure to use your external ip address/hostname and local network configuration.
   
5. When done click the update button.
6. Click Re-Read Configs towards the top of the page.
7. Your system should now be ready for remote VoIP phones. When configuring the VoIP phone to connect remotely use the external ip or hostname for the domain or host settings in the phone.