#snifer

This tool acts much like a standard Ethernet network sniffer. However, unlike a traditional packet sniffer it doesn't attempt to capture and decode all traffic but instead is geared toward discovering useful infrastructure and security-related data from the network, often from traffic not sent to or from the host system i.e. general broadcast network traffic. This data can reveal all manner of useful information, ranging from live systems on the network, hostnames, Ipv6 systems, routers and name servers, user names and passwords.