Cox SIP Trunk for FreePBX Configuration Guide
Cox Communications provides a SIP trunk service through an EdgeMarc gateway installed at your office location. This article covers the configuration of FreePBX to connect to the EdgeMarc gateway and send calls over the Cox SIP trunk.
In order to setup the trunk in FreePBX you will need to have the IP address you provided to Cox for the EdgeMarc gateway. When setting up the service Cox will provide you a BTN number and password. This will be the FreePBX trunk username and password.
Connectivity -> Trunks -> Add Trunk
Be sure to replace () with the appropriate values
Outbound CallerID: (BTN number or number on your account)
CID Options: Block Foreign CIDs
Dialed Number Manipulation Rules
Match Pattern NXXNXXXXXX
Trunk Name: cox
(BTN number):(password)@(EdgeMarc IP)
Cox only allows outbound calls to be placed with a caller ID from a number on your account. If you find calls are being rejected try placing a call from the BTN number, which is your main account number. If this call goes through ask Cox to verify that they have configured your account to allow placing calls from all numbers associated with your account. I ran into this issue and it took Cox tech support almost two hours to resolve.