Abstract: A method of scrambling a stream of data includes obtaining from the stream a succession of first sequences of blocks of data. The order of the blocks is reversed in each of the first sequences of blocks to form respective second sequences of blocks of data. The blocks in each second sequence of blocks are encrypted using a cipher in block chaining mode, initialized with a respective initialization vector for each second sequence of blocks. For a succession of first sequences of blocks included in a unit of data within the stream, at least one initialization vector for encrypting a second sequence of blocks formed from a first sequence of blocks in the unit is generated in dependence on at least one block in a preceding first sequence of blocks of the unit.

Abstract: The invention provides a smartcard, a head-end system and a conditional access system enabling incompatible receivers to be used in a vendor specific conditional access system. Hereto the smartcard stores an operation mode identifier, which is read upon insertion of the smartcard into the receiver and activation of the smartcard. The operation mode identifier is used to select a protocol for communication with the receiver. If the protocol is incompatible with the receiver, the operation mode identifier is changed and another protocol is selected upon reinsertion of the smartcard in the receiver. The head-end system uses data packet encapsulation to enable the receiver to forward EMMs and ECMs to the smartcard.

Abstract: Various embodiments enable a chipset of a receiver of a conditional access system to block cleartext control words provided to the chipset from being used to descramble content. Hereto the chipset comprises a trigger module configured to obtain a disable command that is received with an encrypted Chip Set Session Key (CSSK) and, if the disable command is obtained, have the chipset block any cleartext control word.

Abstract: A method of external data storage in a system including a primary processing device, having a processor and a primary data storage unit, adapted to run application programs for processing active records in the processor and configured to store data belonging to active records in the primary data storage unit; and a secondary data storage system, accessible to the primary processing device, includes loading data belonging to an active record into the primary data storage unit and externalising the record by transferring at least a piece of data belonging to the record to the secondary data storage system for storage. The step of externalising a record includes the making of a call by an application program using data belonging to the record to an interface, arranged to transfer the piece of data to the secondary data storage system.

Abstract: A method of controlling descrambling of a plurality of program transport streams received by a receiver system comprises receiving a sequence of messages in a conditional access sub-system (9,10) comprised in said receiver system, each message being associated with one of a number of scrambled program transport streams and representing a request for returning information enabling the associated scrambled transport stream to be descrambled by at least one descrambler module (12) in the receiver system, determining whether messages received within a certain interval are associated with a number of different scrambled program transport streams, and denying at least one of the requests represented by the messages received in the certain interval, if the number of different scrambled program transport streams with which the messages are associated exceeds a pre-determined number.

Abstract: A method of external data storage in a system including a primary processing device, having a processor and a primary data storage unit, adapted to run application programs for processing active records in the processor and configured to store data belonging to active records in the primary data storage unit; and a secondary data storage system, accessible to the primary processing device, includes loading data belonging to an active record into the primary data storage unit and externalising the record by transferring at least a piece of data belonging to the record to the secondary data storage system for storage. The step of externalising a record includes the making of a call by an application program using data belonging to the record to an interface, arranged to transfer the piece of data to the secondary data storage system.

Abstract: A method of external data storage in a system including a primary processing device, having a processor and a primary data storage unit, adapted to run application programs for processing active records in the processor and configured to store data belonging to active records in the primary data storage unit; and a secondary data storage system, accessible to the primary processing device, includes loading data belonging to an active record into the primary data storage unit and externalizing the record by transferring at least a piece of data belonging to the record to the secondary data storage system for storage. The step of externalizing a record includes the making of a call by an application program using data belonging to the record to an interface, arranged to transfer the piece of data to the secondary data storage system.

Abstract: A method of controlling descrambling of a plurality of program transport streams received by a receiver system comprises receiving a sequence of messages in a conditional access sub-system (9,10) comprised in said receiver system, each message being associated with one of a number of scrambled program transport streams and representing a request for returning information enabling the associated scrambled transport stream to be descrambled by at least one descrambler module (12) in the receiver system, determining whether messages received within a certain interval are associated with a number of different scrambled program transport streams, and denying at least one of the requests represented by the messages received in the certain interval, if the number of different scrambled program transport streams with which the messages are associated exceeds a pre-determined number.