ACL-based data storage controlling the access from processes in DRM client enviromnent

In the process of electronic distribution of digital contents, cryptographic techniques are used to protect the content from unauthorized use. When encrypted content is downloaded into a user's computer and is being decrypted, all of the related keys must be present in the user's computer where malicious attacks and unpredicted exceptions frequently occur. We propose here architecture for DRM client running on our license-based content distribution system. Our design objectives are secure management of keys, flexible support of external viewers, and defensive facilities against malicious attacks.