| 摘要 |
PURPOSE:To exactly prevent an illegal usage in which plural persons can be allowed to pass through a ticket examination gate by using one data carrier, in an automatic checking and collecting machine using the data carrier in which the ticket examination gate can be controlled by using the portable data carrier equipped with a readable and writings memory. CONSTITUTION:A time T1 when a data carrier 20 performs an access to a reader-writer 10 is written in a memory 21 of the data carrier 20. When the access is performed by the data carrier 20, the access time T1 previously written in the memory 21 of the data carrier 20 is read, and a time (T1+alpha) when the next access is valid searched from the read access time is compared with the present time. Then, when the access valid time (T1+alpha) is before the present time, it is decided as a legal usage, and when the access valid time (T1+alpha) is after the present time, it is decided as an illegal usage. |
