Abstract:
According to the invention, a circuit that is capable of automated scan testing is disclosed. Included in the circuit are a cryptographic engine, a digital circuit, an input pin, and an output pin. The cryptographic engine capable of performing at least one of encryption and decryption of one or more digital signals. The digital circuit includes combinatorial logic and a number of memory cells. The memory cells have scan inputs connected serially in a scan chain. The input pin and output pin are coupled to the scan chain. At least one of the input pin and the output pin carries at least some cipher text data of the scan chain.
Abstract:
A system to change security levels is used to change the level of security used in a secured processing system. The system uses a status indicator to designate the security level being implemented. The security level can be upgraded to allow a higher level of security to be implemented with relative ease. However, in order to change from a higher level of security to a lower level of security, an authorization code is utilized to confirm that the change in security is authorized.
Abstract:
A system to transmit a set of programs from a transmitter to a receiver is used to accommodate different levels of security used for each program. When a high level of security is necessary for transmitting or receiving a program the transmitter and/or receiver is operable to accommodate that level of security. Thus, both transmitters and receivers are operable to be reconfigured to encrypt or decrypt, respectively, at different levels. Accordingly, differing amounts of programs can be transmitted or received based on the resource requirements needed at any level of security. Consequently, a high level of encryption/decryption requires more resources and allows the processing of fewer services, while a lower level of encryption/decryption allows more services to be transmitted/received.
Abstract:
A method and apparatus is provided for decrypting an encrypted transport stream, comprising. The method includes receiving the encrypted transport stream over a content delivery network. The encrypted transport stream is encrypted using a first control word that serves as an encryption/decryption key. A variable control word is received over the content delivery network. The variable control word is mathematically constrained to create a second control word. The encrypted transport stream is decrypted using the second control word if the second control word is the same as the first control word.
Abstract:
A secure Internet Protocol (IP) telephony system, apparatus, and methods are disclosed. Communications over an IP telephony system can be secured by securing communications to and from a Cable Telephony Adapter (CTA). The system can include one or more CTAs, network servers, servers configured as signaling controllers, key distribution centers (KDC), and can include gateways that couple the IP telephony system to a Public Switched Telephone Network (PSTN). Each CTA can be configured as secure hardware and can be configured with multiple encryption keys that are used to communicate signaling or bearer channel communications. The KDC can be configured to periodically distribute symmetric encryption keys to secure communications between devices that have been provisioned to operate in the system and signaling controllers. The secure devices, such as the CTA, can communicate with other secure devices by establishing signaling and bearer channels that are encrypted with session specific symmetric keys derived from a symmetric key distributed by a signaling controller.
Abstract:
According to the invention, a method for protecting digital television from unauthorized digital receivers within a population of digital receivers is disclosed. Each digital receiver in the population has a unique identifier. In one step, provisioning information is received from a subset of the population of digital receivers indicating that the subset is potentially within range to receive digital television from a broadcaster. First decryption information is distributed to the subset of the population of digital receivers. The first decryption information allows for potentially decrypting a plurality of programs coextensively in time. The unauthorized digital receivers are cryptographically excluded from using the first decryption information. A first program is encrypted using a first method that is cryptographically related to second decryption information. The first program is sent. The second decryption information is distributed and cryptographically secured with the first decryption information.
Abstract:
An apparatus and method are utilized for transmitting data across an interface between a sender and a receiver. The sender and receiver can be provided with a shared key, a receiver—key and a sender—key. A payload message can be combined with the keys to generate a unique message for transmission across the interface. The payload message can be authenticated utilizing the same input and the same algorithm on the receiving end of the transmission. The resulting confirmatory payload message can be utilized with the authenticating payload message to authenticate the payload message.
Abstract:
A method and apparatus is provided for decrypting an encrypted transport stream, comprising. The method includes receiving the encrypted transport stream over a content delivery network. The encrypted transport stream is encrypted using a first control word that serves as an encryption/decryption key. A variable control word is received over the content delivery network. The variable control word is mathematically constrained to create a second control word. The encrypted transport stream is decrypted using the second control word if the second control word is the same as the first control word.
Abstract:
The present invention discloses a system and method for providing a secured system time reference to a subscriber device, e.g., a set top box or a receiver. In one embodiment, the system time reference is provided in a secure system time message that is broadcasted to a plurality of subscriber devices. Each subscriber device has a security device or software application that is capable of determining whether the received system time reference is legitimate. If the system time reference is determined to be legitimate, a local time reference is synchronized with said received system time reference.
Abstract:
A secure Internet Protocol (IP) telephony system, apparatus, and methods are disclosed. Communications over an IP telephony system can be secured by securing communications to and from a Cable Telephony Adapter (CTA). The system can include one or more CTAs, network servers, servers configured as signaling controllers, key distribution centers (KDC), and can include gateways that couple the IP telephony system to a Public Switched Telephone Network (PSTN). Each CTA can be configured as secure hardware and can be configured with multiple encryption keys that are used to communicate signaling or bearer channel communications. The KDC can be configured to periodically distribute symmetric encryption keys to secure communications between devices that have been provisioned to operate in the system and signaling controllers. The secure devices, such as the CTA, can communicate with other secure devices by establishing signaling and bearer channels that are encrypted with session specific symmetric keys derived from a symmetric key distributed by a signaling controller.