Abstract
Video-On-Demand (VOD) systems provide video services to users on broadband networks. Most of proposed VOD systems are primarily designed for improving their performance. However, it is important to prevent unauthorized users from viewing the videos, provide secure communication and protect private information of each system component from attackers for service providers.In this thesis, a distributed VOD system is designed and implemented on Java platform. The proposed system mainly consists of the VOD manager, the VOD server, and the VOD client. We analyzed the security requirements of VOD systems, discussed several secure protocols, and showed they are not suitable to VOD environments. A secure VOD protocol using cryptography is provided to integrate security features into the system. For the performance of the VOD system, a hierarchical encryption scheme basing on selective encryption is proposed to guarantee real time media transmission.