System for detecting improper rewrites of data system for using separate reader writer passwords
US5455941A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1992 |
| Grant date | Oct 3, 1995 |
| Priority date | — |
| Expiry date | Feb 27, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06Q10/10
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In storing data in one file, consisting of a plurality of blocks of data, a first code is generated by converting a password and a predetermined portion of each of the blocks of data. This portion may be, for example, the data block itself or identification information such as a name. The code is stored in correspondence to the stored data. In reading the stored data, a second code is generated by performing the same conversion on the password and the predetermined portion of the stored data. A comparison is made between the generated second code and the first code stored. Failure of the two to match indicates that an improper rewrite has occurred. In such a case, that occurrence may simply be noted, access to the data may be prohibited; more generally, what processing is performed, or is permitted, is varied according to the result of the comparison.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.