Patent ID: 9385997
Filing Date: 2016-07-05
CPC Classification: H04L,H04N

Claim Text:
1. A method for providing secure transmission of video, wherein the transmission provides for communicating a control word (CW) to a server associated with a conditional access system (CAS), comprising: establishing communication between a client and the server over a secure connection to transmit the video; receiving at the client a control word to be encrypted; encrypting at the client the control word using a first and second key, the first key being a global secret key (GSK) that is known to the client and the server without being communicated over the secure connection, the second key being a control word encryption key (CWEK) that is derived from a locally generated client nonce (CN) and a server nonce (SN) obtained from the server over the secure connection; and sending the encrypted control word (ECW) to the server over the secure connection, wherein the client is a SimulCrypt Synchronizer (SCS) and the server is an entitlement control message generator (ECMG) that generates entitlement control message (ECMs) using the control words received from the SCS.