As the popularity of the computer technology and the constant development of communication technology, the application of the information technology was utilized more widely. Under this background, the issue of network security is exposed gradually. Especially the communication network, it is the core part of the communication system, so it is very important in the whole system. At present, the issue of network security becomes stubborn so that it influences the daily work and life of the public. In order to strengthen the construction of information security, and improve the network security, it is necessary to deeply analyze the network security technology, and then to bring forward the targeted countermeasures. According to the relevant materials, the writer of this thesis takes the present situation of the computer communication network as the breakthrough point, and then discusses and analyzes framework of the network security technologies. In the developmental trend of information technology, the network communication becomes more and more popular, but it also brings about some problems on the security field. In one hand, the network information technology privies the strong driving force to the development of the economy and the society, and most of the industries take the best of this technology and becomes stronger and stronger; but, in the other hand, we have to accept that there still are some defects which could bring about some serious problems. The communication network is suffering the security risks every minutes, no matter these risks are brought about by the defects of the network or the risks that are caused by the defects of the operation system on which the network is run, even the mistakes of the operators, these all could bring about serious threats to the whole communication system, such as the reveal of the confidential data, system failure, etc, they all could bring about the negative influences to the daily production and life of the public. Because of the importance and the specialty of the communication network, and because of the severe circumstance that we have to face, we must strengthen our vigilances to improve the security technology, and draw up some relevant safeguard policies, so as to construct the safe system and safeguard the network communication.
