A sniffer (also called a packet sniffer) is a
|“||program that intercepts routed data and examines each packet in search of specified information, such as passwords transmitted in clear text.||”|
|“||software tool for monitoring network traffic. On a TCP/IP network, sniffers audit information packets.||”|
Sniffers monitor network traffic on wired or wireless networks and capture packets. Packet sniffers generally can be configured to capture all packets or only those with particular characteristics (e.g., certain TCP ports, certain source or destination IP addresses). Most packet sniffers are also protocol analyzers, which means that they can reassemble streams from individual packets and decode communications that use any of hundreds or thousands of different protocols.