A DRM Model for Copyrights Protection based on Hiding Information

There have been researches into digital watermarking technology or Fingerprinting vigorously to safeguard 'Protective rights for knowledge and poverty ' for digital contents. DRM, Digital Rights Management, is not only 'Protective rights for knowledge and poverty', but also management and systems that are necessary to put out, circulate and use for contents. This technology, DRM, encrypts contents to protect digital contents and they are sold users on. Sellers transmit contents with 'Usage Right ' and a license including a key of encryption. The key of encryption decodes encoded files. The right of usage restricts users ' application of contents. Even if digital contents that are applied the DRM are coped illegally and circulated, contents will be protected from that because a player of DRM checks existence of licenses and allows contents to be restored. However, this method might cause users to feel inconvenient since the users can only restore contents through the licenses offered by a player or a Smartcard. If radio as well as cable is used popularly in the future, there will be a lot of limits to use those kinds of players. In the method of that, the method using players need different players in order to work successfully in wired and wireless environment. In the case of using Smartcards, there might be a dangerous situation when the Smartcards disappeared. This paper proposes two kinds of ideas. One is protecting contents from illegal acts such as illegal copies when the contents are in the process of circulation. The other is the protocol that can give users convenience. Hidden Agents are used so that contents are protected from illegal copies and illegal use in the contents and cuts off those illegal acts. The Agent will be installed without any special setup. In addition, it can replace roles of Watermarking as a protection. Therefore, this paper shows the solution of illegal copies that happens frequently.