security system with database.

摘要

An improved security system, including a portable smart card (500) and a host computer (600), eliminates the need for the computer to store individual personal identification (ID) numbers for each user seeking access to the computer. Instead, the computer stores a first encryption algorithm E1 used in converting a particular identification number (ID)n into a secret code Sn for that particular user. Sn also exists within the memory of the smart card having been loaded into its memory at the time of issue. A challenge number C is generated by the computer and transmitted to the smart card. Within the smart card and the computer, microprocessors respond to the challenge number C, the secret code Sn, and a second encryption algorithm E2 in order to generate response numbers Rn and R min n respectively. Thereafter, Rn is transmitted to the computer where it is compared with R min n. A favorable comparison is necessary for gaining access to the computer.