[Asterisk-Users] isdn out of band signalling

[Piotr Chytla]

On Wed, Mar 15, 2006 at 02:01:50PM +1100, James Harper wrote:
> This is more an isdn question than an asterisk specific one, but is
> there any end to end signalling channel available during call setup? Eg
> if AParty dials BParty, can any information be conveyed (in both
> directions preferably, and in addition to CLI[PR]) before the call is
> answered?
>
There is not such thing like A to B signaling, your phone/pbx is sending 
signaling messages to your provider pstn switch not to BParty. 

> The only way I can think of doing this is for the AParty to use CLIP to
> present a different number to the BParty, and for the BParty to
> terminate the call while ringing after a certain time (the time taken to
> terminate forms the information from B to A).
>
On some E1/T1 , you can spoof callerid , everything depends on
your provider.

/pch

-- 
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