Establishing Secure Ethernet LANs Using Intelligent Switching Hubs in Internet Environments

Abstract

Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei,Taiwan 107, ROCEmail: horng@mouse.ee.ntust.edu.twWith increasing security threats in internet environments, we may therefore want to establish asecure mechanism for data transmissions on each network. This paper presents a mechanismfor establishing secure switching local area networks (LANs) by using intelligent switching hubs.Then we can achieve secure internet environments by means of the proposed switching LANs andfirewalls. The proposed intelligent switching hub can easily be implemented and it has a short delaytime. Also the switching LAN structure proposed in this paper is constructed using a symmetrictree, where the leaves represent user stations, the internal nodes represent intelligent switchinghubs, and the links between any pair of nodes (or any pair of node and station) represent full-duplex communication connections. By using the proposed intelligent switching hubs and the linkencryption technique, such a switching LAN can prevent eavesdropping and unauthorized accessby restricting data delivery and stopping unauthorized users from adding devices to the networkto get data. Moreover, it can allow simultaneous communications to exist in different parts of thenetwork, and can isolate certain user stations or subnetworks so that many data transmissions canbe simultaneously and securely accomplished.Received August 30, 1996; revised February 11, 1998