Manufacture Corporation 94-1518PF, User Manual

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
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 or block traffic on the switch port connected to the supplicant
N
OTE
: Suppose two backend servers are enabled and that the server
timeout is configured to X seconds (using the AAA configuration
page), and suppose that the first server in the list is currently down
(but not considered dead).
Now, if the supplicant retransmits EAPOL Start frames at a rate faster
than X seconds, then it will never get authenticated, because the
switch will cancel on-going backend authentication server requests
whenever it receives a new EAPOL Start frame from the supplicant.
And since the server hasn't yet failed (because the X seconds haven't
expired), the same server will be contacted upon the next backend
authentication server request from the switch. This scenario will loop
forever. Therefore, the server timeout should be smaller than the
supplicant's EAPOL Start frame retransmission rate.

Guest VLAN Enabled
When Guest VLAN is both globally enabled and enabled (checked) for a given port, the
switch considers moving the port into the Guest VLAN according to the rules outlined below.
This option is only available for EAPOL-based modes, i.e.:
• Port-based 802.1X
• Single 802.1X
• Multi 802.1X
For trouble-shooting VLAN assignments, use the "Monitor→VLANs→VLAN Membership and
VLAN Port" pages. These pages show which modules have (temporarily) overridden the
current Port VLAN configuration.
Guest VLAN Operation: