The Research on the Principle of Covert Communication and Defense Strategy Based on Sniffer

It is well known that Internet is the largest network covering the whole world. The open protocol of the internet helps the development of the computer network. But the security was neglected in the earlier design of Internet protocol, at the same time the management of Internet was not belonged to the government. All these result in the threats to the Internet. Accidents related to security happen all the time. Information technology is a double-edged sword. When it brings virtues to us, it brings risks to us. The covert technology is a common technology used by hacker, including invasion behavior covert technology, illegal advancement covert technology and hiding communication and so on. The hiding communication is often used in wooden horse or other back door. This article introduces the principle of hiding communication based on Sniffer, gives an example on this technology, and puts forward an effective method in detecting and preventing.