EEE 802.1X is an IEEE standard for port-based Network Access Control; it is part of the IEEE 802 (802.1) group of protocols. It provides authentication to devices attached to a LAN port, establishing a point-to-point connection or preventing access from that port if authentication fails. It is used for certain closed wireless access points, and is based on the EAP, Extensible Authentication Protocol.
This section of the Technical Guide is a discussion of several 802.1x uses and technology. See also the chapter Installing 802.1X authentication in the Installation guide for more practical help on how to get up and running.