E9-1-1
Enhanced 9‐1‐1. An emergency service capability that selectively routes the wireless or wireline emergency service call to the appropriate PSAP and...
Definition:
Emergency Services Routing Key. A number used to route data through the 9‐1‐1 system. A 10‐digit routable, but not
necessarily dialable, number that is used not only for routing but also as a correlator or key for the mating of data that is
provided to a PSAP by different paths, such as the voice path and ALI data path. In daily use, the term ESRK is used to
distinguish operational environments where the “routing” digits are assigned on a per‐destination‐PSAP basis as
opposed to a per origination cell sector basis.