See also: Hacker | Hackerspeak

Term used to describe monitoring data traveling over a network. It is called “sniffing” as if tracking information by smell. This is also known as making a network interface card, or NIC, “promiscuous” instead of “passive” mode.

It can be used for both good and evil, from spying on users to Intrusion detection

Sniffing is a strong motivation for use of encryption, especially over Cable Modems as neighbors can monitor your activity.

Sniffers can be used both for legitimate network management functions and for stealing information off a network. Unauthorized sniffers can be extremely dangerous to a network’s security because they are difficult to detect and can be inserted almost anywhere. This makes them a favorite weapon in the cracker‘s arsenal.
(Developed from the Webopedia Sniffer entry – Copyright 2003 Jupitermedia Corporation All Rights Reserved.)


Sniffing tools

Sniffing detectors

Network Sniffers and Sniffing out network sniffersTakeDown.NET -> “Sniff