Emergency numbers

This recipe guides you through the process of establishing an emergency contact number for your office.

An emergency call, such as 911 in North America, is first routed to a Public Safety Answering Point (PSAP). The PSAP will look up the Automatic Number Identification (ANI), or calling number, from Automatic Location Information Database (ALI database) to determine the caller’s physical address. The ALI database is updated by the PSTN service provider when a customer subscribes to its trunk service. A record in the ALI database is a mapping between a phone number (or trunk) and its physical address.

For each emergency call, the PBX is responsible for setting the correct ANI for the PSAP.