Wireshark

Wireshark: Network protocol analyzer

Wireshark (formerly known as Ethereal) is a free network analysis utility for Windows and Unix operating systems. Wireshark comprises powerful features and it’s the perfect application for network troubleshooting, protocol development and education. The program was developed by networking experts and its open source license supports talented programmers from the network community to add new features and improvements.

Features:

- Allows you to capture data from a live network connection or read from a capture file.
- Capable of reading capture files from tcpdump (libpcap), NAI’s Sniffer, Sniffer Pro, NetXray, Sunn snoop, Atm snoop, Shomiti/Finisar Surveyor, AIX’s Iptrace, Microsoft Network Monitor, Novell LANalyzer, RADCOM’s WLAN/LAN analyze3r, HP-UX nettl, Cisco Secure IDS iplog and many others.
- Reads live data from Ethernet, FDDI, Token-Ring, PPP, IEEE 802.11, Classical IP over ATM and loopback interfaces.
- You can browse the captured network data through the GUI or the TTY-mode.
- Capable of dissecting 602 protocols.
- Options to save/print output as PostScript or plain text.
- Built-in display filters allow you to refine the displayed data and selectively highlight and color packet summary information.
- Allows you to save to disk captured network traces partially or entirely.