Wi-Fi (IEEE 802.11)

Wi-Fi is wireless local area networking built on the IEEE 802.11 family of standards. “Wi-Fi” itself is the certification name of the Wi-Fi Alliance, the industry body that also defines the WPA security programmes. In infrastructure mode, clients associate with a wireless access point that connects them to a wired network; in ad hoc mode, devices talk to each other directly. A network is identified by its SSID. NIST SP 800-153 gives guidance for securing it.

Radio is a shared medium: anyone within range can receive the frames, so protection depends on the link-layer security in use. WEP is broken. WPA was a transitional fix. WPA2 brought AES-based encryption, and WPA3-Personal replaced pre-shared key authentication with SAE. Personal modes rely on a shared passphrase, while Enterprise modes authenticate each user or device through IEEE 802.1X. This protection covers only the radio hop between the client and the access point, not the traffic end to end. Typical threats include a rogue access point, an evil twin and war driving as reconnaissance.

Exam relevance: questions in this area tend to turn on choosing the right security generation and mode for a situation. Candidates are expected to recognise that a hidden SSID or MAC filtering is readily bypassed and is not a substitute for WPA2 or WPA3 encryption and authentication.