(SnifferPor is a network analysis software produced by American Network Associates. It can be used for network fault analysis and function management, and is widely used in the network industry. This book not only introduces the basic knowledge of Sniffer specifically, but also describes the use of Sniffer in network management in combination with the actual situation, including the installation of SnifferPro and Sniffer, the monitoring of network programs using SnifferPro, the use of Sniffer under Linux and network security problems, etc. In order to facilitate readers' understanding, I have selected classic cases to explain based on years of experience in network management and protection work. Each instance is extremely representative. This book is suitable for network management personnel and professional and technical personnel and management personnel in other related fields to read, and can also be used as a core reference book for related courses in colleges and universities.)