Cryptanalysis and Improvement of Two Access Control Schemes with User Authentication in a Distributed Computer network

摘要

In 1998, Jan and Tseng Proposed two inte- grated schemes of user authentication and access control which can be used to implement a protection system in distributed computer systems. This paper will analyze the security of both schemes and show that an intruder can easily forge a login, be accepted an logged in as a legal user, and access system re- sources. We will then propose a modified scheme to withstand our proposed attacks.