Routing ESN (Emergency Service Number)

Routing ESN (Emergency Service Number) is the 3-5 position Emergency Service Number (ESN) used by a selective router to selectively route a 9-1-1 call and for switch-based selective transfer features. In cases where Routing ESNs are not used, the routing ESN equals the Administrative ESN. (Refer to Administrative ESN)

NENA 03-008, NENA Standard for E9-1-1 Default Assignment and Call Routing Functions