Encryption apparatus, decryption apparatus, secret key generation apparatus, and copyright protection system
US7484090B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 2004 |
| Grant date | Jan 27, 2009 |
| Priority date | — |
| Expiry date | Apr 27, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/603
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An encryption apparatus 100a including: a CRL storage unit 111 storing a CRL; a device key ring storage unit 112 storing a device key KD_A specific to each copyright protection module 210a used by a decryption apparatus 200a; a content key storage unit 113 storing a content key Kc that is a secret key for encrypting a content; a hashing function processing unit 114 calculating a hash value of the CRL stored in the CRL storage unit 111 according to a hashing function; and an Ex-OR unit 115 obtaining an exclusive OR value between the hash value and the device key KD_A. The encryption apparatus also includes an Enc unit 116 encrypting the content key Kc using an output value from the Ex-OR unit, and storing the hash value, the encrypted content key and the encrypted content in a DVD2a.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.