Patent ID: RE39622

Claim:
An authentication system for performing authentication processing between a first device and a second device, said first device comprising: first memory means for storing a plurality of data areas and a first plurality of keys, wherein each of said first plurality of keys indicates access to a corresponding one of said plurality of data areas; first generation means for generating a first single authentication key from two or more of the first plurality of keys stored in said first memory means, wherein said first single authentication key indicates access to two or more corresponding of said plurality of data areas; and first communication means for communicating said first single authentication key with said second device, and said second device comprising: second memory means for storing a second plurality of keys equivalent to said first plurality of keys; second generation means for generating a second single authentication key from two or more of the second plurality of keys stored in said second memory means; and second communication means for communicating said second single authentication key with said first device, wherein one of said first device and said second device further comprises encipherment means for enciphering information using a corresponding one of said first single authentication key and said second single authentication key, and wherein another of said first device and said second device further comprises decipherment means for deciphering said information enciphered by said encipherment means using another corresponding one of said first single authentication key and said second single authentication key.