The new method of license key management for content distribution system $key management for grouping content

The importance of copyright protection has increased with the rapid spread of content distribution services. In one means of copyright protection, contents are protected by encryption. In this method, license keys are essential and distributed to decrypt contents. The paper presents a new method of license key management that can manage contents as groups. It uses some group keys in addition to license keys for decrypting content. Each of the group keys can decrypt all contents belonging to each group. As an example of applying the proposed method, a cooking recipe distribution system is introduced.