| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a system for reading access time data about access to tag data from a tag itself and preventing tampering on the time data. <P>SOLUTION: This data tampering preventing system is constructed of a storage part 2, a processing part 3, the tag 1 having a radio transmission/receipt part 4, a writing device 5, and a reading device 6. The processing part has a function for clearing a log stored in the storage part in receipt of a clear request signal from the writing device and a function for writing the clear time and an authentication code in the storage part. The writing device has a function for encrypting the time specified by itself or by a tag processing part based on a previously set encryption rule without respect to the writing time in the storage part by the processing time for creating an authentication code and transmitting it. The reading device has a function for reading the data stored in the storage part, while the processing part or the reading device has a function for decoding the authentication code and creating the time data. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
