Design And Implementation Of An Internal Network Security System

Network Security has become a concerned problem. While people try to protect their Network against outside attacks, they pay little attention to internal security. But it is not easy to detect the inside threats. Because of the following reasons, internal security deserves adequate attention. Internal hosts are easy to connect directly. Employees are familiar with the access control to the internal resources. Classified information translated through Intranet is seldom encrypted and easy to be disclosed. With the increase of the Intranet Applications, users have to remember more usernames and passwords, which are often forgotten or confused. Application administrators also have to maintain the users' rights when users' identities are changed. So a secure and efficient system is necessary to both the users and the application administrators to guarantee the perfect operation of the Intranet System.Secure Internal System (SIS) presented in the thesis is to solve these problems. While protecting the classified information translated through Intranet, SIS provides the users a single sign-on. Application administrators can also manage and maintain users' rights efficiently in SIS.Beginning with a particular case, hidden threats of Intranet are introduced, followed by the objects and general design of the SIS. After the discussion of the function modules, we describe the implementation and operation of SIS in detail from Authentication and Authorization aspects. Brief evaluation and improvement comment is presented at last.