Encryption apparatus and method for synchronizing multiple encryption keys with a data stream
US7242772B1 · kind B1 · utility
185Cited by
19References
39Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 7, 2000 |
| Grant date | Jul 10, 2007 |
| Priority date | — |
| Expiry date | Mar 9, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/63345
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A data stream, such as a digital motion picture, is encrypted in units of one or more blocks, each block having an assigned encryption key. A plurality of encryption keys is assigned to the complete data stream, with a synchronization index provided to map each individual encryption key to its starting data block. Encryption keys and associated synchronization indices are provided separately from the data stream, using one or more additional data transfer mechanisms. An optional offset, randomly generated, allows variation in intervals between data blocks at which encryption by a specific encryption key can be performed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.