Abstract: A method and system for rating programs, the method including, receiving a sample of viewing logs from a plurality of set top boxes (STBs), determining, from the sample of viewing logs, at least groups of viewers sharing similar interests, and groups of programs sharing similar audience, computing time dynamics of rating distribution for the groups of viewers and the groups of programs, and incorporating at least one of the following into broadcast metadata: the time dynamics of rating distributions of the groups of viewers for each of the groups of programs, rating distributions of the groups of viewers for each of the groups of programs marginalized by time, rating distributions of the groups of viewers for each program marginalized by time, relative sizes of each group of viewers, and a mapping of each program to groups of programs, thereby making the broadcast metadata available to the plurality of STBs for use in computing ratings. Related systems and methods are described.

Abstract: A method for enforcing use of certificate revocation lists in validating certificates, the lists being associated with a series of list generation indices such that each list is assigned one index which advances according to a time of generation of the list, the lists and the indices being cryptographically signed, the method including receiving one of the lists and an associated index as an identifier of the one list, checking the certificates against the list, associating each of the certificates, which have been checked against the list, with the index, receiving an enforcement generation index (EGI) associated with a latest list in use, storing the EGI as a last known EGI, and refusing performance of an action associated with a certificate if the one index of the one certificate is earlier in the series than the last known EGI. Related apparatus and methods are also included.

Abstract: A data modeling method for modeling data for an electronic program guide (EPG) at a broadcast headend is described.

Abstract: A method for switching from playing a first compressed data segment to playing a second compressed recorded data segment, the method including playing an uncompressed copy of a start of the second compressed recorded data segment upon switching from playing the first compressed data segment, decoding the second compressed recorded data segment from a preceding random access point, the preceding random access point preceding, in the second compressed recorded data segment, a point at which playing is to be switched to the second compressed recorded data segment, stopping the decoding of the second compressed recorded data segment when reaching a point beyond a point currently being played in the uncompressed copy, and switching to playing the second compressed recorded data segment when playing the uncompressed copy of a start of the second compressed recorded data segment reaches the point at which the decoding of the second compressed recorded data segment was stopped.

Abstract: A method for selecting a section from a streamed broadcast program is disclosed. The method includes receiving a streamed broadcast program, rendering the received streamed broadcast program on a display, selecting a section from the received streamed broadcast program substantially when the section is rendered on the display, and producing an indication signal which enables identification of the section based on a time at which selection of the section was carried out with respect to rendering progress of the streamed broadcast program on the display. Related apparatus and methods are also disclosed.

Abstract: A system including a pseudo-random number generator having a register to store an extended state having a reduced state and a dynamic constant, an initialization module to initialize a part of the extended state based on a Key and/or an Initial Value, a state update module to update the reduced state, an output word module to generate output words, the state update module and the output word module being adapted to operate through cyclical rounds, each round including updating the reduced state and then generating one of the output words, and an update dynamic constant module to update the dynamic constant, wherein in a majority of the rounds, updating of the reduced state and/or generation of the output word is based on the dynamic constant, and the dynamic constant is only updated in a minority of the rounds. Related apparatus and method are also described.

Abstract: An interactive multi-channel game method is described. The method includes providing a first representation of a game element associated with a first channel of a multi-channel system, replacing the first representation with a second representation of the game element associated with a second channel of the multi-channel system, providing a clue associated with the second channel, and receiving a user input representing a user's response to the clue. Related apparatus and methods are also described.

Abstract: In an iterated block cipher, a method for round key encryption and key generation, the method including providing a first function Fi and a second function Fj, providing a round key generation function, the round key generation function being operative to utilize, in any given round, exactly one of the first function Fi, and the second function Fj, providing a round mixing function, the round mixing function being operative to utilize, in any given round, exactly one of the first function Fi, and the second function Fj, utilizing the round key generation function in at least a first round to generate a second round key for use in a second round, and utilizing the round mixing function in at least the first round to mix a first round key with a cipher state, wherein one of the following is performed in the first round the round key generation function utilizes the first function Fi to generate the second round key for use in the second round, substantially simultaneously with the round key mixing function util

Abstract: A method is described for trick mode playback, the method including selecting a key-frame in a recording substantially in the vicinity of a trick mode playback starting position, preparing a decryption key associated with a key period including the selected key-frame, sending the prepared decryption key to a descrambler, thereby enabling decryption of video beginning at the selected key-frame, sending a first number P seconds of decrypted video frames, starting at the selected key-frame, at a predetermined speed for a predetermined number of seconds, to a video decoder, in parallel to the sending P seconds of video frames, choosing at least a second video section to stream to the video decoder, sending a decryption key associated with the chosen second video section to the descrambler, and repeating the steps of selecting, preparing, sending the prepared decryption key, and sending a first number P seconds of decrypted video frames. Related apparatus and methods are also described.

Abstract: A system and a method for secure distribution of digital media content through a packet-based network such as the Internet. The security of the present invention does not require one-to-one key exchange, but rather enables keys, and/or information required in order to build the key, to be broadcast through the packet-based network. The digital media content is then also preferably broadcast, but cannot be accessed without the proper key. However, preferably only authorized end-user devices are able to access the digital media content, by receiving and/or being able to access the proper key. Thus, the present invention is useful for other types of networks in which digital media content is more easily broadcast rather than unicast, in addition to packet-based networks.

Abstract: A system for protecting a chip with an integrated circuit disposed on a first surface, the system including, disposed on the first surface, a first antenna, signal analyzer, chip controller and a signal generator which is operative to supply an outbound signal for transmission by the first antenna, a circuit arrangement, disposed on a second surface of the chip, including a shielding arrangement and a second antenna to receive the outbound signal, the circuit arrangement being operative to transmit a return signal from the second antenna to the first antenna, such that a breach in the shielding arrangement results in a change in, or cessation of, the return signal for detection by the signal analyzer, and a chip controller disposed on the first surface being operative to perform an action on the integrated circuit in response to the detection of the breach. Related apparatus and methods also included.

Abstract: A method for frustrating piracy of a movie, the movie including a plurality of filmed frames, each of the filmed frames including an image, the method including editing the movie prior to projection such that different regions of the image of one of the filmed frames are in different frames so that the different regions will be projected at different times, and repeating the editing for other ones of the filmed frames. Related apparatus and methods are also described.

Abstract: A method and system of optimizing strings comprised in program guide data for transmission is described. The method includes sharing, in the program guide data, a plurality of strings, each string among the plurality of strings including a shared sorting key, implementing an order access of a sorted sharing index, wherein the program guide data and the shared sorting key are comprised in the same data storage structure. Related methods and apparatus are also described.

Abstract: A system and method for providing content to users including a multicast sub-system providing content to multiple users and a unicast sub-system providing content to individual users. The multicast sub-system being operative to push to each of a plurality of user communities, content relating to the community and the unicast sub-system being operative to provide on demand to a user, content which has not been previously pushed to the user.

Abstract: A system for scrambling/descrambling packets of a stream of content, each packet having a must stay clear (MSC) section, the system including an input handler including a receiving module to receive the stream, a characteristic analyzer to analyze the stream in order to determine a data independent characteristic of each packet, and a scrambling /descrambling device operationally associated with the input handler, the scrambling/descrambling device including a receiving module to receive the data independent characteristic for each packet from the input handler, and an Initial Value module to determine an Initial Value for each packet as a function of the data independent characteristic of one of the packets being processed, wherein the scrambling/descrambling device is adapted to scramble and/or descramble the packets based on the Initial Value and a Control Word. Related apparatus and methods are included.

Abstract: A method and an apparatus for protecting digital content, in which an output format for received compressed encrypted digital content is determined based, at least in part, on a rule determining whether clear compressed output format is allowed. When the clear compressed output format is not allowed, the content is received in a form in which it has been encrypted by at least two different encryption methods, and processing of the content comprises a combination of decrypting in accordance with one of the encryption methods and decompression in an atomic operation.

Abstract: A method of accessing program meta-data is disclosed. The method includes receiving a plurality of program meta-data virtual containers, at least one of the virtual containers comprising normalized program meta-data of programs having instances in a plurality of time windows, receiving an input indicating a selected time window, the input at least one of comprises and refers to a time-window identifier identifying the selected time window, and using the time-window identifier to filter the plurality of virtual containers, so as to obtain a subset of the program meta-data which corresponds to the selected time window. Related apparatus and methods are also disclosed.

Abstract: A set-top box system for blocking signaled applications from being run on a set-top box, the system comprising an audio/video service receiving module to receive at least one audio/video service, an application receiving module to receive an application, an application signaling module to manage a first table including signaling information indicating that the application is a signaled application authorized for being run on the set-top box, and an application blocking module to receive a second table including blocking information to block running of the signaled application on the set-top box, the second table being received from a broadcasting Headend, and block running of the signaled application on the set-top box in response to receiving the second table. Related apparatus and methods are also described.

Abstract: A method for hindering detection of information unintentionally leaked from a secret held in a memory unit is described, the method including receiving a triggering event waiting for at least a first amount of time to pass after the receipt of the triggering event, the memory unit being in a non-operational state during the at least a first amount of time after the at least a first amount of time has passed, changing at least one first condition under which the memory unit operates, thereby causing the memory unit to enter an operational state, waiting for a second amount of time to pass after the changing at least one first condition, and changing, after the second amount of time, at least one second condition under which the memory unit operates, thereby causing the memory unit to enter the non-operational state, wherein access to the secret information is enabled only during the second amount of time, and detection of secret information unintentionally leaked is limited during the first amount of time.

Abstract: A system and a method for providing variable security mechanisms for securing digital content, in which a single security mechanism is not used for all content. Instead, at least one characteristic or feature of the security mechanism is varied between units, instances or categories of content. Therefore, even if unauthorized access is gained to a single unit of content, the overall integrity and security of the system for content distribution is not compromised. Preferably, security is provided though a general mechanism, which is then varied in order to provide variable, dissimilar security schemes for different types of content. By “type of content”, it is meant any of a single unit of content, a single instance of content or a single category of content. For example, for a category of content, the content may be characterized according to the identity of the content itself, such as the title of a movie for example, and/or according to the owner of a particular copy of the content.