Outbound callerid


I have asterisk hooked up to 3 ISDN2 lines in the UK. At present we have 14 extensions, each bound to a seperate external number (e.g. 020 7613 ***0, 020 7613 ***1, 020 7613 ***2 etc). When we make outbound calls, the callerid for our number is always the first extension, 020 7613 ***0.

Is there any easy way to get the callerid to show the number bound to that specific phone, rather than the first one?


sure, put the caller id in the extension stanza, and make sure the outbound trunk is not forcing one on.


Thanks for the reply. I’m still quite new with Asterisk, and am not sure what you mean by “”…The relevant part of my extensions.conf reads:

ignorepat => 9
;this is so i only have to include one context
;for outgoing calls on the isdn line
exten => _9.,1,Dial(CAPI/ISDN1/${EXTEN:1})

;this is so i only have to include one context
;for outgoing calls includes all the relevant contexts
include => capi-out
include => emergency[/code]

you need to make sure you pstn provider will let you send them the cid info

what i mean is something like this:

exten => XXX.,Y,SetCallerID(${MYPHONENUMBER})

in the section for each extension…

dswartz is right, that’s how you set caller ID on asterisk. I’m assuming that your ISDN2’s are connected to openreach (the bt network that was) and not telewest or NTL, which seems to be the case based on your area code.

Based on my experience with isdn30 and assuming that these are configured as digital system with DDI numbers - i.e so that when someone dialling in 020 7613 **13 gets thru to extension 13 then you can present any valid DDI in your range over the bearer - i.e. achieve what you want.

If you’re struggling to get it working then drop me a PM or email with your issue and mail address and i’ll drop you a note back.