[Asterisk-Users] 911/Emergency calls + Caller ID

[Dylan VanHerpen]

Problem: 911 calls placed through Asterisk are associated with the 
physical location of where the CO trunks terminate. This is not really a 
problem when all extensions are located in the same building, but when 
Asterisk is used in a campus-like or otherwise networked environment, it 
can get messy.

A common solution is to install a few analog lines at each location, for 
emergency calls only. But by making clever use of Caller ID (and adding 
a 'location' field to extensions.conf), it should be possible to  
properly identify the location of the caller:

exten => 1001,1,John Doe,1223 Bell Ave. Room 51

For this to work, you would have to be able to apply rules to the 911 
context in a dial plan, to replace the *name* portion with the 
*location* portion.

A similar rule could be defined to drop other calls if 911 is dialed and 
all lines are busy (e.g. drop the lobby phone but not the front desk, or 
drop local vs. long distance, caller ID calls vs. non-identified calls, 
etc.).

Getting lengthy, better stop.

Dylan.