Ethereal
From Wikipedia, the free encyclopedia.
Ethereal is a popular computer network debugging and security auditing tool. The functionality it provides is very similar to tcpdump (c.f.), but Ethereal adds a well-designed GUI frontend, and many more information sorting and filtering options. It allows the user to see all traffic being passed over the network (usually an ethernet network but support is being added for others) by putting the network card into promiscuous mode.
