Change inbound CID to be the DID?

Can anyone think of a way to send, only to specific extensions, the DID as the caller ID?

I could use this to route faxes pretty easily.


We could probably whack together a bit of code that you could access by changing the context of the extension that the DID is routed to.

What type of extension? It matters as I am not sure how to populate ISDN ZAP CID on the fly. I do know how to change a SIP peers caller ID from within the dial plan.

I thought about this a little more and I was making it too hard. All I have to do is do a per-DID inbound route and tag the CID there. Once the call finally hits the Hylafax box it will have the DID as a CID prefix and FaxDispatch can handle that (and if it can’t, I can modify faxrecvd to do so.)

Now the only trick is getting calls from a PRI to an analog port so a modem can answer it cleanly. I can either do a channel bank (I have a four port Sangoma card) or get a Sangoma analog card with a fax cable. The latter will probably be less expensive and possibly more reliable, but I’ve tried both options in the past and didn’t have much luck. I know a bit more about all this now, though.

Thanks for the response. If and/or when I ever get this done I’ll write it up for others. I figure even with a channel bank or card and modems it will be cheaper than buying a Eicon Diva or Brooktrout T1 fax board.

I was looking for a fax receive solution and someone pointed me to IAXMode & Hylafax. I’ve now got this set up and it works well.

The thread is here:

Everything is running on the PBX machine & I get faxes emailed to me.

IAXModem is fine for the occasional fax, but it’s not near good enough for high volume faxing. You’ll get about 90% completion rates with any spandsp based solution right now, unfortunately. It’s more trouble than it’s worth for me.


I thought the Sangoman cards support slaved timing mode. With the T1 and the channel bank solution you could slave the channel bank T1 off the telco PRI the calls are originating from.

I would highly recommend you pickup a Carrier Access Corporation Adit 600. It’s a wonderful product.

you would be surprise wrt to iaxmodem and hylafax with a PRI. I have one client, last I checked, he had received maybe 30K faxes (or was it 50K). Had switched from a fax server, and the results are stellar. spandsp seems to have a lot more problems when sitting in asterisk then outside. Also - the hylafax module on the otts site will aid in the integration of the incoming fax to hylafax and has everything you need to preserve the CID and DID since the DID is sent on to iaxmodem which provides it to hylafax. The module is in need of some updating but I will probably do that in the next week or so as I have to do another hylafax install for someone where I will use that module and update it in the process.

It does. I’m just a little apprehensive because the last time I tried this using a channel bank it failed miserably. It’s a Sangoma card and I was trying to use a Rhino channel bank. In addition to never getting a fax to go across the link, I also returned the channel bank and never got my money back (Cylogistics, avoid. Rhino said they weren’t even an authorized reseller, and when I gave them the serial number on the box they said it was very, very old and probably used.)

Philippe, I have iaxmodem configured on this box and it’s going to hylafax. But completion rates are abysmal. I suppose I’m doing something wrong, but no matter what tweaks I’ve tried I still get users complaining that stuff never goes through or that it gets corrupted, but my bank of MultiTech faxmodems just hums along with very few incomplete faxes. I probably get 99% completion rates on the multitechs, which handle the bulk of the faxes, and the individual DID faxes I get, if I’m lucky, a 90% completion rate. And the 10% non-completes are all on the bosses fax DID, of course. :slight_smile: