Nationwide table routing of voice over internet protocol (VOIP) emergency calls

摘要

The present invention is used in an emergency network to identify and provide the correct public safety access point (PSAP) to service an emergency call originating from a Voice Over Internet Protocol (VoIP) subscriber. Data stores in an emergency services network associate PSAPs to an input ZIP code obtained from a street address returned from an MSAG relating to a VoIP call, and PSAPs to an input ESN. An emergency caller's civic street address is matched against a nationwide MSAG data store to result in a MSAG ESN. From the street address, the emergency caller's ZIP code is matched to a PSAP in an appropriate ZIP/PSAP data store. A matching PSAP from both the ZIP/PSAP and PSAP/ESN data stores determines with great reliability the identity of the proper PSAP for that emergency caller.