Device and method for selectively supplying access to a service encrypted using a control word, and smart card
US7477744B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 6, 2002 |
| Grant date | Jan 13, 2009 |
| Priority date | — |
| Expiry date | Jan 15, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2005/91364
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Device (120), smart card (300) and method for selectively supplying access to a service (202) encrypted using a control word. A service (202) is received with an entitlement control message (ECM) (203) comprising authorization data and a specifier of a validity period of the authorization data. The service is decrypted only if the ECM (203) is found valid. The service (202) can be stored on a storage medium such as a DVD. An ECM transcoding module (211) obtains the authorization data from the ECM (203) supplies to writing means (215) a device-specific ECM comprising the authorization data. The device-specific ECM may be encrypted with a key specific to the device (120) and/or comprise an identifier for the device (120).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.