[asterisk-users] Block Collect Calls on ISDN trunk

[Richard Mudgett]

> > How to block collect calls on ISDN trunk?
> 
> You need Asterisk v1.8 or later and check the value of
> CHANNEL(reversecharge) in your dialplan.
> 
> https://wiki.asterisk.org/wiki/display/AST/Function_CHANNEL

> Can you give me an example of how to use this function?

exten => 100,1,Proceeding()
same => n,GotoIf($["${CHANNEL(reversecharge)}" = "-1"]?allow:block)
same => n(allow),Dial()
same => n(block),Hangup()

Please note that CHANNEL(reversecharge) is only valid on ISDN channels.

Richard