[Asterisk-Users] Asterisk in parallel with PSTN [OT]

[Dorn Hetzel]

On Thu, Dec 23, 2004 at 04:25:55PM -0600, Christopher L. Wade wrote:
> Dorn Hetzel wrote:
> >I've got a configuration with PSTN line connected to FXO
> >on TDM400P ringing through to a phone connected on a
> >Sipura SPA-3000.  The phone *does* ring before the
> >caller-id is available.  In fact, it shoes some 
> >alternate message like "waiting for caller id info"
> >right after the first ring and then changes to
> >the real caller-id after the 2nd ring.
> >
> >-Dorn
> 
> I've always wondered if certain IP (regardless of proto) phones could do 
> the same?  Basically initiate the call with fake callerid info and then 
> send an 'update' packet later to inform the phone of the new callerid? 
> Is this possible - even if it is only supported on certain phones?
> 
> If this is possible, then we could modify * to allow the dialplan to 
> (optionally) start before callerid is received and then update the 
> ${CALLERID} variable(s) once the information is available.  There are 
> situations where this is VERY desirable (obviously this only applies to 
> POTS though).
>
Seems like something similar must be going on in my setup,
because * is clearly taking the inbound call from the 
TDM400P/FXO and ringing it through to the Sipura FXS port
before the caller-id info is available.

-Dorn