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PLANET WGSW-5242 User Manual

Page 98

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User’s Manual of WGSW-5242

98

However, if during bootup, the client does not receive an EAP-request/identity frame from the switch, the client can initiate
authentication by sending an EAPOL-start frame, which prompts the switch to request the client's identity

If 802.1X is not enabled or supported on the network access device, any EAPOL frames from the

client are dropped. If the client does not receive an EAP-request/identity frame after three attempts

to start authentication, the client transmits frames as if the port is in the authorized state. A port in

the authorized state effectively means that the client has been successfully authenticated.

When the client supplies its identity, the switch begins its role as the intermediary, passing EAP frames between the client and

the authentication server until authentication succeeds or fails. If the authentication succeeds, the switch port becomes

authorized.

The specific exchange of EAP frames depends on the authentication method being used. “

Figure 4-7-6

” shows a message

exchange initiated by the client using the One-Time-Password (OTP) authentication method with a RADIUS server.

Figure 4-7-6

EAP message exchange

Ports in Authorized and Unauthorized States

The switch port state determines whether or not 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.