A Dynamic Conditional Access System for IPTV Multimedia Systems

An IPTV system that transmits contents through an IP network needs to adopt a conditional access system allowing only authorized subscribers to view premium content as in other Pay-TV systems. IPTV systems adopting one of conditional access systems provided by a specific major vendor have a difficulty in changing the conditional access system loaded on a set-top box or on a removable hardware device, such as Smart card. However, a software download scheme through an IP network enables an IPTV set-top box to change the existing conditional access system in a secure way. This paper proposes a dynamic conditional access system for an IPTV set-top box that securely downloads cryptographic software and dynamically executes the cryptographic software when it is required. Therefore, the proposed system enables an IPTV multimedia system to provide seamless conditional access services to IPTV subscribers without rebooting the IPTV set-top box or replacing a hardware security device while changing the running cryptographic software.