System and method for subscriber interactivity in a television s

System and method for transmitting and receiving variable length

System and method for transmitting entertainment information to

System and method for trusted path communications

System and method for user authentication employing dynamic encr

System and method for user authentication having clock synchroni

System and method of providing system integrity and positive aud

System and method of verifying cryptographic postage evidencing

System and method of verifying the legitimacy of a product again

System and methods for secure transaction management and electro

System and scheme of cipher communication

System at a vehicle for debiting at automatic fuelling

System for and method of authenticating a client

System for controlling access to a function having clock synchro

System for controlling access to a function, using a plurality o

System for controlling access to broadcast transmissions

System for conveying information for the reliable authentificati

System for cryptographing and identification

System for decoding and displaying personalized indentification

System for decoding transmitted scrambled signals