Vulnerability of Control Word in Conditional Access Systems Environment

摘要

This paper deals with the vulnerability and threats to control word in the context of Conditional Access Systems (CAS). Control Word (CW) prevents content from being accessed by unauthorized users. Hence, threat to control word is a direct threat to the content delivering environment. This paper deals with secure transmission of control word in different interfaces and stages of a CAS. We propose a scheme to address control word security at the user-end, which is simple to implement and computationally feasible. The implementation of the proposed scheme is discussed at the various levels, from the pairing phase at the CA provider's end to setup at the user's end.