Revocation of a certificate and exclusion of other principals in a digital rights management (DRM) system based on a revocation list from a delegated revocation authority
US7543140B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 2003 |
| Grant date | Jun 2, 2009 |
| Priority date | — |
| Expiry date | Oct 31, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/603
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A digital certificate identifies an entity as having authority over the certificate to revoke same as delegated by the issuer. The certificate also has at least one revocation condition relating to possible revocation of the certificate. To authenticate the certificate, the identification of the delegated revocation authority, a location from which a revocation list is to be obtained, and any freshness requirement to be applied to the revocation list are determined from the certificate. It is then ensured that the revocation list from the location is present and that the present revocation list satisfies the freshness requirement, that the revocation list is promulgated by the delegated revocation authority identified in the certificate, and that the certificate is not identified in the revocation list as being revoked.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.