| 摘要 |
A method and apparatus for providing improved security for a personal identification number (PIN) in a personal identification and verification system of the type wherein a time dependent nonpredictable code is generated at a device in the possession of the individual (36), which code is unique to the individual and this code is communicated to, and compared with a nonpredictable code generated at a central verification computer (46). In this system, the PIN is mixed with the nonpredictable code before transmission of these values to the central verification computer (38). A nonsecret code (30) is previously transmitted to the central verification computer and is used by the verification computer to retrieve the PIN and independently generate the time dependent appropriate nonpredictable code for the user (74). These retrieved PIN and generated code values are used by the verification computer either (a) to strip the PIN from the transmitted nonpredictable code (42) and the stripped PIN and remaining nonpredictable code are compared with the corresponding retrieved values in order to determine verification (44, 46); or (b) to be mixed and then compared with the mixed PIN and code which is transmitted to the verification computer (144). |
