Design Of Firewall For Local Area Network

According to the net safety's practice require of the Agency and the School etc. and the development of the Internet and intranet. This paper puts forward a net safety product—Net firewall system. It protects the data of intranet and prevents from Hikers of the Internet attack to the services act.The Firewall system includes three parts: Firewall system, Client control software and Route communication software.The firewall system's base platform uses LINUX OS, which safety capacity is better than others. Adapting its kernel makes it more safety and more stable. This is a base condition for a safe product. The firewall system functions include: Data packets filter with status detection, NAT (network address translate), Transparent agency, Firewall information location etc. besides these, other functions include: connecting the Client port and accepting or translating the datum between two parts. This is whole system kennel part.The client software's function is: sending control parameters to the Firewall system and accepting data information from firewall system. For making users convenient to manage the firewall system, the interface of the control software is redacted by VC++ language. GUI and style of windows. Moreover, a simple user's guide is companioned a function. The function of Route communication is: connecting client port and firewall system, sending and accepting the dates, makes the dates correct and integrate. It uses SOCKET interface program of TCP/IP protocol. The system has been designed; it has applied in many companies and schools. Such as the TV university of DongHai;DongHai ECTV etc.