Protecting ASF Movie on VOD

Abstract

Easiness of creating and distributing digital information is increasing the production of the digitalized movies. However, since digital content is easy to make copies and it can be distributed through internet which is open to anyone, the problems in security and intellectual property become important issues. These problems are occurred at local content saved in users’ PC until recently. Encrypting the full content is one solution to protect saved content. Streaming content has solved these problems by removing data immediately after processed. But, recently some hacking tools have been appeared, which can save the streamed data. So, streamed media is also not free for illegal use any more. Protecting scheme for streamed content is more complicate because the streaming server must be considered. If the full content file is encrypted, the streaming server cannot transmit the content because the encrypted content may be unknown type to the streaming server. In this paper, we propose a DRM-based streaming system which can not only protect streamed ASF content but be easily integrated with existing ASF streaming system. ASF is the multimedia file format of Microsoft. To explain our system, we describe some related technology, service architecture, encryption scheme and decryption scheme of our system.