Revocation information updating method, revocation information updating apparatus and storage medium
US6581160B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2000 |
| Grant date | Jun 17, 2003 |
| Priority date | — |
| Expiry date | Apr 5, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/00086
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A storage medium (PM) 13 includes a controller 130 and two types of storage regions, the concealed region 134 and the open region 131. The open region 131 includes an open RW 133 storing a digital content, an open ROM-W region 132a storing, as revocation information, identification information of an electronic appliance that is prohibited from accessing the digital content, and an open ROM region 132 storing, as master revocation information, identification information of an electronic appliance that is prohibited from updating the revocation information. When the storage medium is loaded into an electronic appliance that has identification information which is registered in the open ROM region 132, the controller 130 prohibits the electronic appliance from updating the revocation information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.