Emergency Phone Number Services - E911 - AudioCodes Mediant 1000 User Manual

The figure below illustrates an example of implementing an Application server:
9.4

Emergency Phone Number Services - E911

The device supports various emergency phone number services. The device supports the
North American emergency telephone number system known as Enhanced 911 (E911),
according to the TR-TSY-000350 and Bellcore's GR-350-Jun2003 standards. The E911
emergency system automatically associates a physical address with the calling party's
telephone number, and routes the call to the most appropriate (closest) Public Safety
Answering Point (PSAP), allowing the PSAP to quickly dispatch emergency response (e.g.,
police) to the caller's location.
Typically, the dialed emergency number is routed to the appropriate PSAP by the telephone
company's switch, known as a 911 Selective Router (or E911 tandem switch). If the PSAP
receives calls from the telephone company on old-style digital trunks, they are specially
formatted Multi-Frequency (MF) trunks that pass only the calling party's number (known as
Automatic Number Identification - ANI). Once the PSAP receives the call, it searches for the
physical address that is associated with the calling party's telephone number (in the
Automatic Location Identification database - ALI).
SIP User's Manual 530
Mediant 600 & Mediant 1000
Document #: LTRT-83306