[Freeswitch-dev] Call relaying (ISDN <> Freeswitch <> ISDN)

[Markus Müller]

Hello Freeswitch Developers,

ISDN in germany (maybe also somewhere else) has a feature, which colides
with the design of a dialplan: it sends the numbers the user types into
his phone LIVE (!) through the ISDN network. If the number is complete,
the ISDN network tells it to the caller; Only now the call get
established (means the dialplan gets invoked). So you have to do an own
step (live and interactive determination of the number) BEFORE the
dialplan comes in line.

Because this is object not supported by freeswith, in the following
situation

User <-> Analog Phone <-> Siemens Hipath <-> ISDN <-> [FreeTDM <->
Freeswitch <-> FreeTDM] <-> ISDN <-> World <-> ISDN Destiation

you have to do "overlap dialing". Means, freeswitch waits some seconds
until the user has entered the last number and then it goes directly to
the dialplan.

-> This is not what I need!

I want that it works as if there is no FreeSwitch in between. Means,
freeswitch should relay each number the user types into his phone to the
ISDN on the remote side, and make the dialplan stuff AFTER the number
has been dicovered for completeness.

How do you think this should be implemented? If nobody has an object, I
would code this the following way into FreeTDM: If I get a call with a
starting number I know that it must go to the external ISDN (means: a
second dialplan), I first relay the typed numbers and determine the full
number. Only now, when I got the full number, I would give this call to
the higher layers.

What you think about this?

Regards,
Markus Mueller