Wireshark is a network protocol analyzer (or "packet sniffer") that can be used for network analysis, troubleshooting, software development, education, etc. This guide shows how to install and use it on an Ubuntu Feisty Fawn desktop to analyze the traffic on the local network card.
Wireshark is an open source network protocol analyzer. It allows you capture packets from a network interface and then analyze their contents. Wireshark can be downloaded and installed from Ubuntu’s repositories: