Security arrangement for downloadable cable television converters
US4712239A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1986 |
| Grant date | Dec 8, 1987 |
| Priority date | — |
| Expiry date | Jun 16, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/8193
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus prevent unauthorized programming viewing via a downloadable cable television converter. A booter checksum is computed from data contained in a downloaded booter image. A valid checksum is extracted from tag data associated with a scrambled program signal transmitted on the cable system. The booter checksum is compared to the extracted valid checksum. If the booter checksum and valid checksums match, a descrambler is enabled to descramble the scrambled program signal. If the checksums do not match, the descrambler is not enabled. In this manner, a pirate is prevented from downloading a false booter image to defeat the integrity of the converter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.