Which of the following are characteristics of 802.1X Authentication? (Select Three)

The choice regarding Extensible Authentication Protocol is correct because 802.1X uses EAP as its framework for providing authentication. EAP is a versatile authentication protocol that allows various authentication methods to be employed, such as username/password combinations or digital certificates, making it suitable for different network environments.

In addition to this, 802.1X is characterized by its support for RADIUS as an external authentication server. This allows for centralized management of authentication credentials, enhancing security and administrability across multiple access points and user devices.

Another fundamental characteristic of 802.1X is port-based authentication. In this model, the switch or network device acts as a gatekeeper, allowing or denying network access based on the authentication state of the device attempting to connect. This provides a robust mechanism for controlling access to the network, ensuring that only authenticated devices can communicate.

Both the support for RADIUS external authentication and the implementation of port-based authentication are key features of the 802.1X standard, making the option for Extensible Authentication Protocol, as well as the others not selected, integral to understanding how this authentication method functions within network environments.