IRC
Internet Relay Chat
A chat protocol historically used for botnet command and control.
IRC is a text chat protocol that predates modern messaging and was historically abused as a command and control channel for botnets. Infected hosts would join a channel and await instructions from an operator, making channel traffic a useful detection signal. Defenders monitor for outbound connections to IRC ports from systems that have no legitimate reason to use them. Newer malware often favors HTTPS or peer to peer channels to blend with normal traffic.
Looking IRC up is step one. Getting tested on it is step two.
A free account opens all 4 Domain 1 objectives, 271 exam-style questions with a lesson and a lab on each, a placement check that skips what you already know, and a dated plan. No card.
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