Patent ID: 9647980
Date: 2017-05-09
CPC Classifications: H04L,H04M

Claim:
1. A method, comprising: receiving, by a processing system including a telephone number mapping server in a mapping system, the telephone number mapping server comprising a processor, a first request from a call session control function server for a name authority pointer associated with a telephone number of a call session, wherein the call session control function server and the telephone number mapping server are co-located in a first geographic region, wherein the mapping system comprises a national domain name system server and a name authority pointer database and a plurality of regional name authority pointer servers in communication with the national domain name system server, wherein at least one of the regional name authority pointer servers includes a mirror image of the name authority pointer database; searching, by the processing system, according to the telephone number of the first request, by the telephone number mapping server, a plurality of entries stored in a cache memory of the telephone number mapping server to determine if the name authority pointer is stored at the cache memory, each entry of the plurality of entries comprising a name authority pointer transmitted to the telephone number mapping server in accordance with a previous call session; if the name authority pointer is stored at the cache memory, then: if the name authority pointer is not stored at the cache memory, then: