Internet的出现更使信息以前所未有的速度进行传播,但同时在网络上数据包的传输过程中,信息很容易被干扰,滥用,遗漏和丢失,甚至被泄露、窃取、篡改、冒允和破坏,同时还有可能受到计算机病毒的感染等等。根据美国FBI的调查,美国每年因为网络安全造成的经济损失超过170亿美元,在全球平均每20秒钟就发生一次网上入侵事件。日益严峻的计算机信息安全问题已经成为每个拥有计算机和网络的企业与组织都要面临的挑战。 The advent of the Internet also makes information disseminate at an unprecedented rate, but at the same time, information is easily interfered with, misused, omitted and lost during the transmission of data packets on the Internet, and even leaked, stolen, tampered with, threatened and destroyed, At the same time may also be infected by computer viruses and so on. According to a survey conducted by the U.S. FBI, the U.S. economy suffers more than $ 17 billion in annual economic losses due to cybersecurity, with an average of every 20 seconds of online cybercrime in the world. The growing problem of computer information security has become a challenge for every enterprise and organization that has computers and networks.