Asterisk Sirrix Channel Variables

Sirrix channel driver channel variables


The behavior of the Sirrix ISDN channels can be controled by various channel variables. Some incoming ISDN protocol elements can be accessed by channel variables.


  • REDIRECTIONPN: Redirection Party Number
  • REDIRECTINGPN: Redirecting Party Number *)
  • USERUSER_IA5: IA5 coded User-User signalling data *)

*) This variable is also set automatically by an incoming call on a Srx-channel when the corresponding ISDN information element is present.

Variables must be set *before* the new Srx-channel is created. Use the underscore "_" to make Asterisk copy the variable to the new channel.


exten => 1234,1,SetVar(_REDIRECTINGPN=5678) ; set variable to some value
exten => 1234,2,Dial(Srx/gMyGroup) ; call destination party

This will present a redirection with "redirecting party number" = 5678.


Variables on the *calling* channel can also be updated after the channel is created. Updates are propagated each time an "indication" (like Progress, Alerting, ...) is sent to the calling channel.

By this mechanism you can inform the calling party immediately when the call is being forwarded to a new destination by simply setting the REDIRECTIONPN channel variable *before* the new destination is being called.

exten => 1234,1,Dial(firstdestination|10) ; call first destination with timeout
exten => 1234,2,SetVar(_REDIRECTIONPN=newdestination) ; inform calling party
exten => 1234,3,SetVar(_REDIRECTINGPN=firstdestination) ; inform called party
exten => 1234,4,Dial(newdestination) ; call new destination


To *overwrite* a previously written variable starting with a "_", you first have to clear the variable's contents (without "_" !!).

exten => 1234,1,SetVar(_REDIRECTINGPN=5678) ; set variable to some value
exten => 1234,2,SetVar(REDIRECTINGPN=) ; clear variable again
exten => 1234,3,SetVar(_REDIRECTINGPN=0815) ; set variable to some other value

Created by: sirrix, Last modification: Thu 04 of Aug, 2005 (11:48 UTC)
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