A PKI based digital rights management system for safe playback

In this paper we first propose an I-frame encryption scheme for encryption of moving image video data. Second, we propose a licensing agent which provides automatic user authentication and data decoding when multimedia data encrypted in the system server is executed in the client system by the user. The licensing agent performs user authentication based on Public Key Infrastructure (PKI) using a shared key pool and encryption/decryption of multimedia data. After designing and implementing the proposed system, performance tests were then performed using video data files of various sizes for performance evaluation. We verified that the proposed system significantly reduces delay time, including decryption time, when playing back video data files in the client system compared with existing systems.