随着计算机网络的发展和普及,局域网已成为人们工作不可缺少的组成部分,同时由于网络协议存在很多安全漏洞,导致网络木马和病毒的快速传播。通过对ARP协议内容、工作原理和协议漏洞的介绍,说明了ARP欺骗的原理和危害,展示了局域网诊断和防御ARP欺骗的重要性。 With the development and popularization of computer networks, local area networks have become an indispensable part of people’s work. At the same time, there are many security holes in network protocols, resulting in the rapid spread of network Trojan horses and viruses. Through the introduction of ARP protocol content, working principle and protocol loopholes, the principle and harm of ARP spoofing are described, which shows the importance of LAN diagnosing and defending ARP spoofing.