System for decrypting encrypted software
US5875247A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1995 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Aug 1, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/121
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A CD-ROM stores encrypted software. When a user desires to decrypt and install this software, an approval preparatory key is generated by an installer. This approval preparatory key is generated based on time data. When the user informs a center of this approval preparatory key, the center calculates a difference between this approval preparatory key and a decrypting key and vends this calculated result to a user in the form of an approval key. When the user inputs this approval key to an installer, the installer generates a decrypting key by adding the approval preparatory key to the approval key. The installer decrypts the software by this decrypting key and installs the encrypted software into a personal computer system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.