Interlogix NS3552-8P-2S-V2, User Manual

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Chapter 4: Web configuration
NS3552-8P-2S-V2 User Manual 213
Ports in authorized and unauthorized states
The switch port state determines if the client is granted access to the network. The port
starts in the unauthorized state. While in this state, the port disallows all ingress and
egress traffic except for 802.1X protocol packets. When a client is successfully
authenticated, the port transitions to the authorized state, allowing all traffic for the
client to flow normally.
If a client that does not support 802.1X is connected to an unauthorized 802.1X port,
the switch requests the client's identity. In this situation, the client does not respond to
the request, the port remains in the unauthorized state, and the client is not granted
access to the network.
In contrast, when an 802.1X-enabled client connects to a port that is not running the
802.1X protocol, the client 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 that causes 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.