Patent ID: 6105134
Filing Date: 2000-08-15
Classification: H04L,H04N

Abstract:
A method, in a cable television system comprising a programming source and a set top terminal, of verifying said programming source at said set top terminal, the method comprising the steps ofat said programming source,providing said programming information, a control word, and a shared secret as inputs to a secure hash function;using at least a portion of an output from said secure hash function as a source authentication;encrypting said control word to generate an encrypted control word; andtransmitting said source authentication, said programming information, and said encrypted control word; andat said receiver,receiving said source authentication, said programming information, and said encrypted control word;decrypting said encrypted control word to recover therefrom said control word;providing said programming information, said control word, and said shared secret as inputs into said secure hash function;using at least a portion of an output from said secure hash function as a receiver authentication; andcomparing said source authentication with said receiver authentication, the programming information and the control word being authentic when said source authentication and said receiver authentication are the same.