ettercap -- ettercap is a ncurses-based sniffer/interceptor utility<hr>
<a href="http://ettercap.sourceforge.net/">http://ettercap.sourceforge.net/</a><hr>
ettercap is a network sniffer/interceptor/logger for ethernet LANs (both
switched or not).  It supports active and passive dissection of many
protocols (even ciphered ones, like SSH and HTTPS). Data injection in an
established connection and filtering (substitute or drop a packet) on the
fly is also possible, keeping the connection sincronized. Many sniffing
modes were implemented to give you a powerful and complete sniffing suite.
Plugins are supported. It has the ability to check whether you are in
a switched LAN or not, and to use OS fingerprints (active or passive)
to let you know the geometry of the LAN.  The passive scan of the lan
retrives infos about: hosts in the lan, open ports, services version,
type of the host (gateway, router or simple host) and extimated distance
in hop.
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