Setting up an Inbound Number with FreePBX can be tricky. There are a few different things to consider and in the past I’ve written some posts for setting up specific call providers. This post will try to describe what the different options mean, and will hopefully help you set up a DDI number with any provider.
The first thing you need to know is that all SysAdminMan templates have “Allow Anonymous Inbound SIP Calls” set to No. This means that an unknown SIP server can not pass a call to your system to be processed. This is to help prevent hackers route calls through your system. It’s strongly recommended that you leave Anonymous SIP calls set to No, unless you really know what the implications are when setting it to Yes.
So, if we don’t let any SIP servers pass calls to us then we need a way to tell FreePBX to allow calls from our DDI provider. We do this by setting up a SIP trunk.
Setting up a SIP trunk
We are going to put all of the settings under “Outgoing settings”, and leave “Incoming settings” blank. This is a little confusing to say the least! but we are not creating a user on our system for the call provider to connect to, we are just allowing their IP. So we add a new SIP trunk and see these details –