Patent ID: 7325065

Claim:
A method for determining whether a client communication system seeking access to a host communication system is authorized to do so, the method comprising: receiving, at the host, from the client communication system, a user-independent client-communication-system-specific identifier and results of a first mathematical computation performed at the client on a first user-dependent access identifier and the user-independent client-communication-system-specific identifier; accessing, at the host and based on the receipt of the user-independent client communication-system-specific identifier, a second user dependent access identifier; performing a second mathematical computation using the accessed second user-dependent access identifier and the user-independent client-communication-system-specific identifier received from the client communication system; comparing results of the first and second mathematical computations; and designating a client communication system as unauthorized based on the comparison of the results of the first and second mathematical computations, wherein the user-independent client-communication-system-specific identifier is derived from information that identifies at least a hardware component or aspect of the client communication system.