Encryption method, decryption method, and recording and reproducing apparatus
US7155011B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 2002 |
| Grant date | Dec 26, 2006 |
| Priority date | — |
| Expiry date | Jan 7, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/24
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to an encryption method for encrypting information including a series of multiple unit blocks, one at a time, a decryption method for decrypting multiple encrypted unit blocks, one at a time, and a recording and reproducing apparatus that uses those methods. The seed of an encryption key for encrypting each unit block and the seed of an encryption key for decrypting each encrypted unit block, which are used by those methods and the recording and reproducing apparatus, are based on a unit block that is one or more unit blocks before the current unit block in a reproduction order or on information generated by encrypting one or more unit blocks before the current unit block. Alternatively, the seed of an encryption key for encrypting each unit block and the seed of an encryption key for decrypting each encrypted unit block are information based on an encryption key for encrypting a unit block before the current unit block in a reproduction order.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.