An Essential Sys Admin and Security Tool
Wireshark

Photo by Anton Chernyavskiy on Unsplash
Wireshark fills the gap between security and system administration for those who need to know more about what’s flowing through the wires or over the airwaves in the corporate network.
Special Thanks: This article was made possible by support from Linux Professional Institute
Wireshark is an essential system administrator and security tool for any network. That broad statement covers a lot of ground, but it is true nonetheless. Even on the Wireshark website, the About page refers to it as “the world’s foremost and widely-used network protocol analyzer.” It began life in 1998 with the name Ethereal, but the authors had to change it a few years later due to a trademark problem for the original author, Gerald Combs. Wireshark is cross-platform, free, and open source.
Understanding Wireshark
Wireshark is a network protocol analyzer -- sometimes referred to as a packet analyzer or as a network sniffer (see the “Caution” box). It offers live network packet capture and offline analysis. If you’ve ever used Wireshark, or any network sniffer, you know that it only takes a few minutes to capture thousands of packets. For this reason, Wireshark has a very powerful display filter, which you’ll learn to love, because who really needs to see thousands of “Who has” Address Resolution Protocol (ARP) messages, unless that’s what you’re looking for in a capture?
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