Patent ID: 7529371

Claim:
A system for authenticating a client device requesting a session of service from a service provider, comprising: a first one-time pad cryptological table accessible by a cellular telephone service security server, said first table having multiple sequenced entries, each entry including a field for an indicator of previous use, said previous use indicator for each entry being initialized in an “unused” state, each entry containing at least one One Time Pad value; a second one-time pad cryptological table stored in an authentic cellular telephone device, initially synchronized with said multiple entries, fields, and indicators of previous use of said first one-time pad cryptological table; a first copy of said second one-time pad cryptological table stored in a cloned inauthentic cellular telephone device, said first copy being initially synchronized with said multiple entries, fields, and indicators of previous use of said second one-time pad cryptological table; a code transmitter portion of said authentic cellular telephone device configured to select an unused entry in said second one-time pad cryptological table, and to transmit said selected entry to a telephone network upon requesting initiation of a service session; a code exchanger portion of said cellular telephone service security server configured to receive a One Time Pad value from said authentic cellular telephone device and from said cloned inauthentic cellular telephone device upon request for initiation of a service session; a code comparator portion of said cellular telephone service security server configured to determine that said received One Time Pad value matches a sequentially next entry marked “unused” in said first one-time pad cryptological table; a service session grantor configured to grant said service request responsive to determination that said received One Time Pad value matches a sequentially next unused entry, including changing said used indicator to a “used” state in said first one-time pad cryptological table upon said grant of service, and further configured to disable service to said cloned inauthentic cellular telephone device responsive to determining that said first one-time pad cryptological table is not synchronized with said first copy of said second one-time pad cryptological table; and a table updater portion of said authentic cellular telephone device configured to, responsive to granting of said service request, mark said transmitted One Time Pad as “used”, wherein said first one-time pad cryptological table and said second one-time pad cryptological tables are kept in synchronization.