Chapter 4: Web configuration
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NS3552-8P-2S-V2 User Manual
switch receives EAPOL frames and relays them to the authentication server, the
Ethernet header is stripped and the remaining EAP frame is re-encapsulated in the
RADIUS format. The EAP frames are not modified or examined during
encapsulation, and the authentication server must support EAP within the native
frame format. When the switch receives frames from the authentication server, the
server's frame header is removed, leaving the EAP frame which is then
encapsulated for Ethernet and sent to the client.
Authentication initiation and message exchange
The switch or the client can initiate authentication. If you enable authentication on a
port by using the dot1x port-control auto interface configuration command, the switch
must initiate authentication when it determines that the port link state transitions from
down to up. It then sends an EAP-request/identity frame to the client to request its
identity (typically, the switch sends an initial identity/request frame followed by one or
more requests for authentication information). Upon receipt of the frame, the client
responds with an EAP-response/identity frame.
However, if the client does not receive an EAP-request/identity frame from the switch
during bootup, the client can initiate authentication by sending an EAPOL-start frame
which prompts the switch to request the client's identity.
Note:
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. The diagram below shows a message exchange initiated by the client using the
One-Time-Password (OTP) authentication method with a RADIUS server.
Summary of Contents for NS3552-8P-2S-V2
Page 1: ...NS3552 8P 2S V2 User Manual P N 1073552 EN REV B ISS 25JAN19 ...
Page 41: ...Chapter 3 Switch management NS3552 8P 2S V2 User Manual 39 ...
Page 73: ...Chapter 4 Web configuration NS3552 8P 2S V2 User Manual 71 ...
Page 147: ...Chapter 4 Web configuration NS3552 8P 2S V2 User Manual 145 ...
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