Promiscuous mode

Promiscuous mode, in computer related fields, is generally used to refer to the practice of putting a network card into a setting so that it can see all the traffic being passed over the network, which is usually ethernet. Some programs like ethereal, tcpdump, and airsnort (for wireless LANs) make use of this feature to show the user all the data being transferred over the network. Some programs like FTP and Telnet transfer data and passwords in clear text, without encryption, and network scanners can see this data. Therefore, computer users are encouraged to stay away from programs like telnet and use more secure ones such as SSH.