Design And Implementation Of Network Security Controller

With the development of information technology, computer has been used widely in nealy all the fields, so is the network technology. At present, network, as an open system to public, is facing all kinds of threats and attacks. Meanwhile, the technology of hackers is being improved and the tools for hackers are spreading without restricton. As a result, the netuser's computers have been attacked and will be easily attacks, which makes the system face the risk. Therefore, the security issue of network is more and more important. And so is the structure of security system. How to protect the internal data from spreading, and how to keep the internal computer from being attacked are the important issues.Although there are sorts of firewalls with powerful and total functions, how to research an effective and unifying firewall is still difficult and important. In this essay, lots of technologies of network safety have been analyzed; an idea of solving the safety in network is also presented; a network security controller programming system has been designed.The thesis has refined and summarized the technologies of network security through thorough researches, inquiries and summaries by means of referring to the internet, reading books from the library and so on. The refined and summarized theories have not only brought forth the ideas in designing the program to build up the program model but also provided theoretical framework for the thesis. By referring to voluminous technical books on VB and compiling and experimenting the program developed in VB 6.0, the thesis finally put theories into practice and then in use.The main purpose of the essay is of drawing into the network security technology as controller programming system. It deals with cpaturing data packet; makes keyholed back plate changed and saved with packet filtering;realised saving and reading log files. The programme provides very good scecurity and can be installed and used instantly, which can potect the computer systems in nets.