Interlogix NS3500-28T-4S User Manual - Manual (Page 225)

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initiates the authentication process by sending the EAPOL-start frame. When no response is received, the client sends
the request for a fixed number of times. Because no response is received, the client begins sending frames as if the
port is in the authorized state
If the client is successfully authenticated (receives an Accept frame from the authentication server), the port state
changes to authorized, and all frames from the authenticated client are allowed through the port. If the authentication
fails, the port remains in the unauthorized state, but authentication can be retried. If the authentication server cannot
be reached, the switch can retransmit the request. If no response is received from the server after the specified
number of attempts, authentication fails, and network access is not granted.
When a client logs off, it sends an EAPOL-logoff message, causing the switch port to transition to the unauthorized
state.
If the link state of a port transitions from up to down, or if an EAPOL-logoff frame is received, the port returns to the
unauthorized state.
4.9.1.2 802.1X Setting
This page allows you to configure the IEEE 802.1X authentication system.
The IEEE 802.1X standard defines a port-based access control procedure that prevents unauthorized access to a
network by requiring users to first submit credentials for authentication. One or more central servers, the backend
servers, determine whether the user is allowed access to the network. These backend (RADIUS) servers are
configured on the "Security→802.1X Access Control→802.1X Setting" page. The IEEE802.1X standard defines
port-based operation, but non-standard variants overcome security limitations as shall be explored below.
The 802.1X Setting and Information screens in Figure 4-9-3 & Figure 4-9-4 appear.
Figure 4-9-3 802.1X Setting Page Screenshot
The page includes the following fields:
Object Description
 802.1X Indicates if NAS is globally enabled or disabled on the switch. If globally
disabled, all ports are allowed forwarding of frames.