[Asterisk-Users] DID on TDM400P Question?

[Chris Coulthurst]

I could see something working only if the telco was able/willing to set up a 
circuit that sends dtmf digits immediately after a circuit answers (kind of 
like some analog voicemail systems do on FXO ports).  The context upon 
answering would have to take the digits and dialout accordingly to the right 
devices.

This, however, would require two miracles, an act of congress, and a note to 
the telco from santa claus.

Chris Coulthurst
chris at shuksan.com

----- Original Message ----- 
From: "Rich Adamson" <radamson at routers.com>
To: "Asterisk Users Mailing List - Non-Commercial Discussion" 
<asterisk-users at lists.digium.com>
Sent: Wednesday, August 17, 2005 8:59 PM
Subject: Re: [Asterisk-Users] DID on TDM400P Question?


>
>>  Does anyone know if the current TDM400 card can take DID digits from the 
>> LEC?
>> If so is there any reference to how to set this all up?  As I get my 
>> current
>> service from my LEC over an IAD, so would be sweet to just have trunks, 
>> not
>> each channel specific to a number.
>>
>>  Also if the above is possible, if the line is being used for DID, then 
>> is
>> this only workable for inbound, or can I also seize the line and use it 
>> for
>> outbound calls.  I know with PRI's that is easy, but never had to play 
>> with
>> this on an analog port level.  Just having a PRI at home isn't practical, 
>> so
>> not something I can really do.
>
> Not likely to work. Part of the reason is the TDM card essentially answers 
> a
> call when ringing occurs. That "answer" essentially closes the tip-ring 
> loop
> to the pstn (central office), and the central office will interpret that 
> as
> a change in line status. The central office will not forward any more 
> digits
> (dial pulse or dtmf) when that occurs.
>
> If the TDM card supported E&M signaling, then one would have the signaling
> structure (to the central office) to support the wanted DID function; but
> that doesn't exist and the TDM chipset doesn't support E&M. Last, the 
> asterisk
> code would need to change in such a way as to listen for additional dtmf 
> digits
> _after_ the TDM card closed the tip-ring loop, and I believe that code 
> doesn't
> exist either. (Even if the code did exist, then what method would be used 
> to
> signify to the central office that a call was answered by an asterisk 
> phone?)
>
> Bottom line... not with a TDM card.
>
>
> _______________________________________________
> Asterisk-Users mailing list
> Asterisk-Users at lists.digium.com
> http://lists.digium.com/mailman/listinfo/asterisk-users
> To UNSUBSCRIBE or update options visit:
>   http://lists.digium.com/mailman/listinfo/asterisk-users
>