Rightfax server with Brooktrout Analogue interfaces to cisco Voice gateway

Unanswered Question
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Paolo Bevilacqua Tue, 09/04/2007 - 12:54


from past dicussion on this forum, it appears that with the router, you can receive analog DID, but not generate it, at least you cannot exactly reproduce the protocol use by N.A. switches with analog DID (wink). There is a a paper that explains the DID protocol in detail on Brooktrout's website.

The VIC card would be VIC2-4FXO and could work in delay start mode.

Paolo Bevilacqua Wed, 09/05/2007 - 02:18

Yes, I think I've partecipated to these thread, and the confusion is about sending and receiving DID, that are two very different things. A VIC-4FXS/DID would be able to receive DID, a VIC2-4FXO _should_ be able to send DID.

I have not seen yet someone with a working configuration to send DID to the brooktrout card, I suppose it's doable, but not having one to test, I can't confirm.

If you go back in the mentioned thread you will find a link to the white paper that explains analog DID, and why you need an FXO card to work with it. remember, in DID, is the 'user side' that provides current loop, not the CO !

pacameron Thu, 09/06/2007 - 05:57

We have made these work a few times in the past. The cards expect work as a FXO interface, and expect battery feed from the external device. To make these work on IOS gateways, use a FXS card on the router, and H323 operation to allow the POTS dial peer to send digits out the voie port.

The cards will answer on ring signal from the FXS port and expect DTMF digits to route the call to the correct fax mailbox number. This is why you need H323 operation - MGCP will supress the DTMF tones from being sent out the voice port. You also need a 'prefix ,,' to add a delay as the cards are a bit slow to answer.

A config like this should work -

dial-peer voice 1000 pots

description - fxs port to fax card

destination-pattern 1...

port 0/1/0

prefix ,,1

This will send numbers in the range 1XXX towards the fax card

Paolo Bevilacqua Thu, 09/06/2007 - 06:19

Good info, but I suppose it is related exclusively to the models that are FXO as indicated.

True analog DID supplies current loop from the user side (the card in this case), expect no ring for incoming, and can use either a wink start or delay protocol to initiate reception of DTMF digits.

That is the case where in the past there has been some discussion on how to make it work with cisco devices. I assume an FXO if not an E&M should be able to do the job.


This Discussion