Radio-over-IP module for AsteriskNOW / FreePBX (resurrected project)

I am resurrecting a project planned for a couple of years ago, and discussed briefly here at that time, to implement a Radio-over-IP module for FreePBX that will add the capability, administered by FreePBX, of tying our Civil Air Patrol wing’s PBX into its radio network. That project was placed on the back burner at the time and is now taking shape again.

Our CAP wing has a PBX, based on the ancient AsteriskNOW 2.0.2 and soon to be upgraded to AsteriskNOW 612. The server is located in my home and there are several dozen phones implemented around the state, most of which are at Wing HQ about 35 miles from here, and the rest in members’ homes. The phones are mostly Grandstream GXP1400 with a few of a different model, and some smartphone VoIP apps and XLite softphones. The SIP protocol is used exclusively.

The objective is that anyone can pick up one of those phones and dial a 3-digit number, and be connected to an HF SSB channel to communicate with ground teams in the field anywhere in the state, or a VHF ground-to-air channel to communicate with aircraft.

I would like to implement this as a FreePBX module, to be administered with FreePBX Admin->Module Admin, and show up under Applications->Extensions or something else under Applications, like Applications->RoIP.

I know there are several solutions out there that involve dedicated Asterisk installations for RoIP, mostly directed to the amateur radio community, implementing things like VoIP/RoIP repeaters and hybrid radio/IP networks. I have looked at all I can find, and installed a couple of them in VirtualBox virtual machines, and so far haven’t seen a clean way to migrate to an existing AsteriskNOW / FreePBX installation. But, that’s probably just because I don’t (yet) know anything about Asterisk modules and how to implement / integrate them.

Regarding how to implement PTT, I’m not sure yet. The easiest approach from the user’s perspective would be to implement a VOX approach, but that would be subject to the varying levels of background noise (which could be quite high) in an event-management environment in a room full of people all yelling at one another. The other approach would be to force the phone user to punch a set of keys to switch the remote transmitter between transmit and receive, perhaps “*” for transmit and “#” for receive.

Any thoughts on how best to approach all of this would be much appreciated.



Remember that AsteriskNow and FreePBX are simply Asterisk Management programs. Intergrating Asterisk modules is different than adding a FreePBX module.

If you don’t already have the Asterisk source code, I’d recommend looking at the source for a channel driver to see what needs to happen there. Once you get the Asterisk channel driver built, you can decide what management activities are required to establish your FreePBX module.

You might also want to contact Motorola and see if they can help you with their VOIP-ROIP bridge technology.

Finally, you should contact your servicing base Comm Squadron, although they aren’t likely to be as much help as they would have in the past. We are moving away from local support and moving toward centralized support.

1 Like

Take a look to this motorola product:

Cisco have it too and have a lot and a lot of years, it run over cisco call manager. This product is called IPICS.

You can run both products using cisco old and new routers. They have some new routers called IS-IS that give you a fully P25 integration with Call-ID and encrypted radio channels.

Thanks for the information Frank. I’ve actually sold WAVE systems in this market, so I was aware of this product when I responded to the thread at the time.

It’s good information, but has absolutely nothing to do with any of the things we were talking about in this thread from a year ago. That’s not really cool.

Basically, it’s Motorola SPAM for a product that costs several thousand dollars and would require a significant upgrade in the Civil Air Patrol’s radio network and repeater system. It does what the CAP in this particular instance was looking to do, but does not do it the way the implementer was looking to do it.

I sold of them too :slight_smile:

Basically I start with cisco because them.
Any cisco support LMR starting with the 2600 XM.
You can setup a multi-site multicast net with them.

Is a little bit hard use multicast so because that I’m playing with freepbx and cisco.

I have it working using the freepbx conference, the only trouble is that the conference do not implement VAD and keeps streaming when you have silence, this activate the VAD at the local router so the radio keeps in TX mode.

If I can set-on VAD at the conference is done.

Best Regads!

I know this is a few years old, but was there anything developed out of this? I work with an EMS company that’s just upgraded their mobile clinic trailer to a voip phone system, and they want to integrate the radio into the phones.