Emergency 911 by Subnet

Anyone know how to pump out a different CallerID for Emergency 911 dialing based on what subnet the extension is registered on?

I’ve got a single box driving multiple sites w/ Aastra telephones using the XML Scripts & Hotdesking in Extension mode, and I need to pump out the correct CLID based on the location of the telephone (which doesn’t move)… as the extension may be registered from one site a certain day, and a completely different site the next.


understand, I mis-interepreted how you were setting up.

You could write some custom dialplan and use the predial hook to check the subnet of the registered IP address and set the CID based on that.

The Emergency CID is tied to the device not the user, so if you set up the Emergency CID info on the devices you will have the correct 911 setup.

Beyond that you would have to write some custom dialplan to review the IP address of the calling device.

The site is using extension-mode and not deviceanduser because they only wanted any given user/extension to only be registered at one place at a time (not multiple locations as in deviceanduser)… so if x123 registers from location-A, and the next day at location-B… the Emergency CID of 5551234567 remains the same regardless of location (tied to that ‘extension’).

They could use deviceanduser-mode if there was a way to limit the number of allowed registrations to ‘1’, but there’s also some reliability issues (I believe) w/ Aastra’s XML Scripts in deviceanduser-mode. I believe they solved many of the inconsistencies on their end in the current release, but understand their upcoming 2.3.1-release to solve the remaining problems and bug fixes.