Improvement of secure access control agent for distributed files

In 1998, we proposed an access control agent system for distributed files. This agent works as a proxy for authors of the files and enables the authors to control their files. The agent restricts the software access of the user who does not obey the condition for the usage of distributed files. However, in this agent system there is an assumption on the role of system participants. Without this assumption the agent system actually faces a problem called role problem and can be abused by the system participants. In this paper, we propose a solution for the role problem in which the rights of authors are protected more securely in the use of distributed files.