Introduction At present, there are many SNIFF tool software, such as Windows Environments, the most famous tools are Netxray and Sniffer Pro, which is very convenient to analyze them in a Windows environment. In a UNIX environment, such as Sniffit, Snoop, Tcpdump, DSNIFF, etc. are more common. Here is a simple network Sniffer implemented with C language and network packets and analyzing development tools libpcap and winpcap. The network sniffer block diagram first gives the process as shown in Figure 1. Figure 1 flow chart