Emergency Service Query Key (VoIP)
The ESQK identifies a 911 call instance processed through a VoIP Positioning Center (VPC). An ESQK is associated with a Selective Router/Emergency Service Number combination. The ESQK is used to route the call and is delivered to the PSAP as the calling number/ANI for the call, and is subsequently used by the PSAP to request ALI information for the call. The ALI database includes the ESQK in location requests sent to the VPC. The ESQK is used by the VPC as a key to look up the location object and other call information associated with an emergency call instance. The ESQK is a non-dialable North American Numbering Plan (NANP) number in the format of NPA-NXX-XXXX.