进入21世纪以来,计算机网络信息系统的快速发展打破了国家的界限,给这个世界带来了自由和繁荣,人们对于计算机网络信息系统的依赖也不断加深。但与此同时,计算机网络攻击、计算机网络犯罪等各种网络安全威胁却愈演愈烈,严重影响着各国经济社会的稳定和发展。本文系统分析了Do S攻击、ARP欺骗攻击的基本原理,提出了相应的解决和防护办法,从而有效抵御和防范了针对计算机网络信息系统环境问题的主要威胁。 Since the 21st century, the rapid development of the computer network information system has broken the boundaries of the country, brought freedom and prosperity to the world, and people’s reliance on the computer network information system has also deepened. However, at the same time, various cyber security threats such as computer network attacks and computer cybercrimes have intensified, seriously affecting the economic and social stability and development in various countries. This paper systematically analyzes the basic principles of Do S attacks and ARP spoofing attacks and puts forward corresponding solutions and protection measures to effectively resist and prevent the main threats to the environment of computer network information systems.