Method for transmitting and receiving a multimedia content
US9544276B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 2011 |
| Grant date | Jan 10, 2017 |
| Priority date | — |
| Expiry date | Mar 12, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/60
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method for transmitting and receiving multimedia content having cryptoperiods scrambled by a control word includes a sender using an operating key and an encryption algorithm in a first virtual mother card to encrypt the control word to obtain a cryptogram, using a syntax constructor also in the first virtual mother card to generate an ECM that incorporates the cryptogram, and transmitting it to a terminal. The terminal receives the ECM and using a syntax analyzer contained in a first virtual daughter card associated with the mother card and uses it to locate a position of the cryptogram CW*t in the ECM. Using an operating key of a decryption algorithm in the daughter card, it then decrypts the cryptogram. Then, using the decrypted control word, it proceeds to descramble the cryptoperiod. Meanwhile, the sender occasionally changes the virtual mother card into a different virtual mother card.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.