Wireshark is the world's most-used network protocol analyzer - and learning to read packet captures is one of the highest-leverage skills a network or security engineer can build. This tutorial takes you from your very first capture all the way to decrypting TLS handshakes and writing custom dissectors, with hands-on examples for every common protocol.
We start with the basics (how to capture, how filters work, how to build reusable profiles), then dive into TCP internals - sequence numbers, retransmissions, zero-window, fragmentation. From there we cover HTTP, DNS, ARP, TLS decryption, IPsec, Kerberos, LDAPS, RADIUS, and the security-side topics that come up constantly in real incidents (rogue DHCP, duplicate IPs, malicious resource detection, log4j-style traffic analysis).
Click Start the course to begin with "How to use Wireshark", or jump straight to the protocol you are troubleshooting. The TCP, TLS, and Security chapters are the most-bookmarked.
