Doing some digging (Score: 0) by Anonymous Coward on 2014-09-12 22:14 (#2SC1) Some other articles have stated the system needs a claimed ID or the caller's phone number to help narrow the list of records, then does verification of the voice against the "voiceprint" on record. I don't think comparing the caller's voice over thousands of records is particularly efficient for this application (NSA may be a different story)