802.1x: Introduction and general principles

IEEE 802.1X is an IEEE Standard for port-based Network Access Control to prevent unauthorized devices from gaining access to the network. It defines the encapsulation of the Extensible Authentication Protocol (EAP) over IEEE 802, known as “EAP over LAN” or EAPOL. 802.1X authentication involves three parties: a supplicant, an authenticator, and an authentication server.
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