[Asterisk-Users] T1 to T1 on asterisk?

[Gary]

Maybe I'm off on a tangent with this ???
Maybe its just terminology (I stand to be corected pls).

On Mon, 25 Aug 2003 10:10:24 -0500 (CDT), Mark Spencer wrote:

>> How does the portmaster distinguish between an incoming ISDN call
>> and incoming analog call?  I know this can be done, my local ISP
>> can handle ISDN and analog calls on the same phone number and it
>> must know when the call comes in.
>
>You could look for HDLC framing...

I would have thought that the portmaster knows how to answer the call
according to the bearer information passed on the "D" channel from the
CO ?

>> Whatever method the portmaster uses to tell those apart should be
>> applicable to * to disable the echo cancel.  This might be as
>> simple as "voice" versus "data" call (is that info provided by
>> the PSTN?).  Is the echo cancel needed on voice ISDN calls?  I
>> can live with no support for voice ISDN calls (can imagine why I
>> would ever get one).
>
>You could also try to look at voice vs. data, yah.
>

If the "D" channel information equals a "voice" call, the Access server
woudl normally switch in a modem,

I think the real problem with ISDN4Linux is that it was written "data
centric", it would problably be quite easy (for someone with the
appropriate skills) to come up with a patch to default echo
cancellation except when its a data-type call. Unfortunately the voice
was really a tack on...