A Lightweight Key Agreement Protocol between Smartcard and Set-Top Box for Secure Communication in IPTV Broadcasting

CAS(Conditional Access System) is used in Pay-TV System to prohibit unauthorized user(s) accessing the contents in IPTV broadcasting environment. In the CAS, Smartcard transfers CW which is necessary in the process of descrambling the scrambled program to STB. CW hacking problem is one of the most serious problems in pay-TV system. There have been many researches on generating secure communication channel between smartcard and STB for secure transmitting, But they had problems in efficiency and security. In this paper, we propose a lightweight key agreement protocol based on a symmetric key algorithm. We show that our proposed protocol is more efficient than existing protocols by comparing the amount of computations, and analyzing the security requirement of the proposed protocol.