Efficient Authorized Domain DRM System without Revocation List

The current DRM system has been focusing on restricting the content usage and limiting user rights for the content. Thus, the concept of AD (Authorized Domain) was proposed to remove such inconvenience and limitations. However, the previous works on AD have two problems. The first is that it requires a rather expensive revocation mechanism. The second is that the content obtained in AD can still be played, even if it is outside AD. To solve these problems, we propose a secure and efficient content management scheme without revocation list.