Packet sniffer

A packet sniffer (also known as a network analyzer or protocol analyzer or, for particular types of networks, an Ethernet sniffer or wireless sniffer) is computer software or computer hardware that can intercept and log traffic passing over a digital network or part of a network. As data streams travel back and forth over the network, the sniffer captures each packet and eventually decodes and analyzes its content according to the appropriate RFC or other specifications.
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<networking, tool> A network monitoring tool that captures data packets and decodes them using built-in knowledge of common protocols. Sniffers are used to debug and monitor networking problems.
(1995-03-28)