[chan-capi-users] Release Cause "Number Changed 22" with New number

[Armin Schindler]

On Fri, 16 Jan 2009, Saeed Ahmed wrote:
> Hi all,
>
> Since long I am searching for a way to return Number changed (22) release
> cause with new modified number to my TDM switch (SS7/DSS1) which is
> connected to asterisk on PRI line, but I found no way, asterisk dev also
> replied with no. Finally someone referred me to chap-capi that its possible
> with it. Could you please guys ensure me if its possible? Here's what I am
> trying to do:
>
> 1  When call comes from  my TDM switch
>
> 2  I want to return Number changed release cause (22), additionally with new
> modified number
>
> 3  So that my TDM switch can re-route the call according to routing (in that
> case the call could go to some other switch instead of capi asterisk box,
> based on routing)
>
> The similar thing I am able to do in SIP with Transfer() application.

I cannot tell anything about SS7, but when talking about DSS1 it seems this 
is not completely possible.
First you want to release the call with a special cause code. Looking at 
this only, it will work (if the ISDN card driver supports it, but most CAPI 
drivers do). With chan_capi you can Hangup() with any cause code.

But then you want the call to be rerouted to new number!? Well then the 
first step (release) should not be done. For BRI lines you can use 
call-deflect which is supported by chan_capi. With PtP BRI lines and PRI
the same chan_capi function triggers call-reroute. But this must be 
supported by the hardware driver as well (and the switch!).

Armin