Wireshark is the world’s foremost network protocol analyzer, and is the de facto (and often de jure) standard across many industries and educational institutions.
Wireshark development thrives thanks to the contributions of networking experts across the globe. It is the continuation of a project that started in 1998. Many of you will know it as Ethereal.

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After nearly 10 years of developement Wireshark (formely known as Ethereal) has finally reached version 1!
For those that don’t know, Wireshark is the world’s foremost network protocol analyzer, and is the de facto (and often de jure) standard across many industries and educational institutions.
Wireshark development thrives thanks to the contributions of networking experts across the [...]

NetworkMiner is a passive network sniffer/packet capturing tool for Windows with an easy to use interface. It can detect operating systems, sessions, hostnames, open ports etc. without putting any traffic on the network. NetworkMiner can also parse PCAP files for off-line analysis.
NetworkMiner makes use of OS fingerprinting databases from both p0f (by Michal Zalewski) and [...]

Packet sniffing goes hi-tech? What’s wrong with ethereal?
The equipment that technician Mark Klein learned was installed in the National Security Agency’s “secret room” inside AT&T’s San Francisco switching office isn’t some sinister Big Brother box designed solely to help governments eavesdrop on citizens’ internet communications.
Rather, it’s a powerful commercial network-analysis product with all sorts of [...]