TH49985A - Digital multimedia terminal equipment And removable modules that work with terminal devices that contain copy-protected interfaces. - Google Patents

Abstract

DC60 (18/12/43) The end device (1) receives the encrypted data stream (TS(D.EMB.)) in which the encrypted control word (CW) is sent. The end device then transmits this stream via the interface (ITTS) to the decryptable module (2), which has conditional access specific to the provider of the data. Module (2) extracts and encrypts the control word (CW) from the stream before transmitting it to the end device via the second interface (ITCOM). These control words are then used by the end device's decoder (16) to decrypt the data. The stream from the module (TS(D.EMB.)) contains only the encrypted data, thus ensuring better copy protection. The end device (1) receives the encrypted data stream (TS(D.EMB.)) in which the encrypted control word (CW) is sent. The stream is sent in an encrypted format. The end device transmits this stream via the interface (ITTS) to a decryptable module (2) that has conditional access specific to the provider of the data. Module (2) extracts and encrypts the control words (CW) from the stream before sending them to the end device via the second interface (ITCOM). These control words are used by the end device's decoder (16) to decrypt the data. The stream from the module (TS (D.EMB.)) contains only the encrypted data, thus ensuring better protection against duplication.

Claims (16)

1. A digital multimedia terminal (1) intended for receiving a stream (TS(D.EMB.)) of digital data encoded by a control word (CW) encapsulated in the stream (TS(D.EMB.)) in cryptographic form, and intended to work with a pull-out module (2) for decoding the stream. Such terminal, capable of sending the encoded stream (TS(D.EMB.)) to the pull-out module, is unique in that it is also capable of receiving the decoded control word (CW) from the pull-out module and contains a decoder (16) capable of decoding the digital stream using the control word (CW) received from the pull-out module (2). 2. The digital terminal under claim 1 has a special characteristic because it is also capable of receiving encrypted data streams (TS'(D.EMB.)) from the extracted module (2), and such data streams received by the terminal are not altered from the data streams (TS(D.EMB.)) sent by the terminal. 3. The digital terminal under claim 1 has a special characteristic because it is also capable of receiving encrypted data streams (TS'(D.EMB.)) from extractable modules (2) in which control words (CW) have been removed from the data streams (TS(D.EMB.)) sent by the terminal. 4. Any digital terminal under claims 1 through 3 is unique in that it is capable of transmitting encrypted data streams (TS(D.EMB.)) to a pull-out module via the first interface (ITTS) with the pull-out module, and it is also capable of receiving decrypted control commands from the pull-out module via the second interface (ITCOM) with the module. 5. The terminal device under claim 4, in combination with claims 2 and 3, is unique in that it is also capable of receiving encrypted digital data streams (TS'(D.EMB.)) from the extractable module (2) through the first interface (ITTS). 6. A digital multimedia terminal (1) intended for the stream (TS(D.EMB.)) of digital data encrypted by a control word (CW), in which such stream (TS(D.EMB.)) contains a control word encrypted by the first key (K), and intended to work with a decryptable module (2) for decryption of such stream. Such terminal, capable of sending the encrypted stream (TS(D.EMB.)) to the decryptable module via the first interface (ITTS) to the decryptable module, is characterized by the ability to also receive the decrypted control word (CW), encrypted by the second key (SSK K2), before being sent via the second interface (ITCOM) to the decryptable module (2), from the decryptable module, and in which it contains - a tool for decrypting the received control word. From the decoded module, using the second key (SSK S2) and - the decoder (16) is able to decode the digital data stream (TS(D.EMB.)) using the decrypted control word (CW). 7. Module (2) intended for use with the digital terminals under claim 1, which is capable of receiving encrypted digital data streams (TS(D.EMB.)), is characterized by the ability to - extract the encrypted control word (CW) from the TS(D.EMB.)), - decrypt the control word, and - transmit the decrypted control word (CW) to the terminal. 8. The module under claim 7 is unique because, in addition, it can be used to transmit encrypted digital data streams (TS(D.EMB.)) back to the end device without altering the data stream itself. 9. The module under claim 7 is unique because, in addition, it can be used to send encrypted digital data streams (TS(D.EMB.)) back to the end device while removing control phrases from the TS(D.EMB.) sent by the end device. 10. Any module under claims 7 through 9 is special because it is capable of receiving digital data streams (TS(D.EMB.)) through the first interface (ITTS) with the end device (1) and also capable of sending decoded control commands to the end device through the second interface (ITCOM) with the end device. 11. Any module under claims 7 through 10 is unique because it is capable of working with a detachable security element (3) for decryption of the control message. Such module is capable of: - extracting the encrypted control message (ECM) from the digital data stream (TS(D.EMB.)); - transmitting the ECM to the security element (3) inserted into the module; - receiving the decrypted control message (CW) from the security element (3); and - transmitting the decrypted control message to the digital terminal (1) with which the module works. 12. Module (2) intended to work with the digital terminal under claim 6, which is capable of receiving encrypted digital data streams (TS(D.EMB.)) from the terminal via the first interface (ITTS) with the terminal (1), is special because it is also capable of - extracting the encrypted control word (CW) from the data stream (TS(D.EMB.)), - decrypting the control word, and - encrypting the control word using a second key (SSK K2), and - transmitting the encrypted control word (CW) to the terminal via the second interface (ITCOM) with the terminal. 13. A module under either claim 10 or 12 is unique in that it is identical to a DVB-CI standard module and its first interface (ITTS) is the MPEG-2 data stream interface and its second interface (ITCOM) is the control interface. 14. The method for decoding a stream (TS(D.EMB.)) of digital data encrypted by a control word (CW) received by a digital multimedia terminal (1), in which the control word (CW) is embedded in the stream in its encrypted form, and which consists of a first step involving the transmission of the encrypted stream (TS(D.EMB.)) to the decryptable module (2), is unique in that it also consists of steps for the decryptable module (2) - extraction of the encrypted control word (CW) from the stream (TS(D.EMB.)) - decryption of the control word and - transmission of the decrypted control word (CW) to the terminal. 15. The method for decrypting the encrypted digital data stream (TS(D.EMB.)) encrypted by a control word (CW) received by a multimedia terminal (1), which encrypts the control word (CW) using the first key (K), is unique in that for the decryptable module it also consists of: - extracting the encrypted digital data stream (TS(D.EMB.)) - decrypting the control word - encrypting the control word (CW) using the second key (SSK K2) - sending the encrypted control word (CW) to the terminal; and for the terminal (1) it consists of: - decrypting the control word (CW) using the second key (SSK K2) and - decrypting the encrypted digital data stream using the encrypted control word (CW). The code has been decoded. 16. The method for transferring control words (CW) between a module under any of Rights 7 through 13 and a digital terminal under any of Rights 1 through 6 is unique in that it consists of the following steps: - for module (2), the first object ("CPTS_identification( )") is sent to terminal (1); - for terminal (1), the second object ("CPTS_identification_answer( )") is sent, indicating whether the terminal is capable of receiving the control word from module (2) in response to the first object; and - for module (2), upon receiving an answer from the second object, the control word (102a 102b 102i) containing the control word (CW) is sent to a third object ("CPTS_SW").