| As the human beings go into information times, the technology of computer, communication and network was developed and popularized constantly. Many local area networks were set up to server for themselves in some departments of government and enterprise. The problem of protecting the security of network and the information resource was been paid more attention. It is necessary to supervise and manage the illegal connection to outside network in order to prevent the members of local area network from connecting illegally. It is easy to be ignored that there is an important hidden security trouble in the popular network supervision with the Client / Server mode. That is, a secret channel is established to connect the local area network with internet while the inside member connects the host computer to internet by dialing up on the telephone. So the virus, hostility code, and nocuous data in internet can easily break into the local network and the network security is terribly influenced. In order to overcome the problem, the network supervision system for illegal connection to outside network based on dual machine structure is analyzed and studied in this article. The structure of the system is simple and the management is convenient. From the design it realized to zero mistake report and it can centralize the management in distribution system for large network.From analyzing the status of network supervision for illegal connection to outside network, the article points out the hidden security trouble in supervision system with the Client / Server mode and the security threat caused by dialing up on the telephone. The network supervision system for illegal connection behaviors based on dual machine structure is studied to solve those problems. Based on introducing the key technologies of the supervision system, the paper emphasized on analyzing the hidden security trouble of network security system causedby dialing up on the telephone and analyzes the processing flow of inspection scanning and alarm treatment in detail. The article introduces the whole design and the function design of the system. And also the design and realization of each subsystem is given in the article. At last, the measurement is taken on the supervision system. The measurement result is given in the paper and the analysis on the result is also given in the paper. Then the paper gives the actual evaluate of the system performance and draw a conclusion. |
