Web Management
4
Port Configuration
The table has one row for each port on the selected switch in the stack and a number of columns,
which are:
Port
The port number for which the configuration below applies.
Admin State
If NAS is globally enabled, this selection controls the port's authentication mode. The following
modes are available:
Force Authorized
In this mode, the switch will send one EAPOL Success frame when the port link comes up, and any
client on the port will be allowed network access without authentication.
Force Unauthorized
In this mode, the switch will send one EAPOL Failure frame when the port link comes up, and any
client on the port will be disallowed network access.
Port-based 802.1X
In the 802.1X-world, the user is called the supplicant, the switch is the authenticator, and the
RADIUS server is the authentication server. The authenticator acts as the man-in-the-middle,
forwarding requests and responses between the supplicant and the authentication server. Frames
sent between the supplicant and the switch are special 802.1X frames, known as EAPOL (EAP Over
LANs) frames. EAPOL frames encapsulate EAP PDUs (RFC3748). Frames sent between the switch
and the RADIUS server are RADIUS packets. RADIUS packets also encapsulate EAP PDUs
together with other attributes like the switch's IP address, name, and the supplicant's port number on
the switch. EAP is very flexible, in that it allows for different authentication methods, like
MD5-Challenge, PEAP, and TLS. The important thing is that the authenticator (the switch) doesn't
need to know which authentication method the supplicant and the authentication server are using, or
how many information exchange frames are needed for a particular method. The switch simply
encapsulates the EAP part of the frame into the relevant type (EAPOL or RADIUS) and forwards it.
When authentication is complete, the RADIUS server sends a special packet containing a success
or failure indication. Besides forwarding this decision to the supplicant, the switch uses it to open up
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