User manual

C HAPTER 4 | Configuring the Switch
Configuring Security
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If (re-)authentication fails or the RADIUS Access-Accept packet no
longer carries a VLAN ID or it's invalid, or the supplicant is otherwise no
longer present on the port, the port's VLAN ID is immediately reverted
to the original VLAN ID (which may be changed by the administrator in
the meanwhile without affecting the RADIUS-assigned setting).
This option is only available for single-client modes, i.e. port-based
802.1X and Single 802.1X.
N OTE : 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.
RADIUS Attributes Used in Identifying a VLAN ID
RFC 2868 and RFC 3580 form the basis for the attributes used in
identifying a VLAN ID in an Access-Accept packet. The following criteria
are used:
■
The Tunnel-Medium-Type, Tunnel-Type, and Tunnel-Private-Group-
ID attributes must all be present at least once in the Access-Accept
packet.
■
The switch looks for the first set of these attributes that have the
same Tag value and fulfil the following requirements (if Tag == 0 is
used, the Tunnel-Private-Group-ID does not need to include a Tag):
■
Value of Tunnel-Medium-Type must be set to “IEEE-802” (ordinal
6).
■
Value of Tunnel-Type must be set to “VLAN” (ordinal 13).
■
Value of Tunnel-Private-Group-ID must be a string of ASCII
characters in the range 0-9, which is interpreted as a decimal
string representing the VLAN ID. Leading '0's are discarded. The
final value must be in the range 1-4095.
The VLAN list can contain multiple VLAN identifiers in the format
“1u,2t,3u” where “u” indicates an untagged VLAN and “t” a
tagged VLAN.
◆ Guest VLAN Enabled - A Guest VLAN is a special VLAN - typically with
limited network access - on which 802.1X-unaware clients are placed
after a network administrator-defined timeout. The switch follows a set
of rules for entering and leaving the Guest VLAN as listed below.
The “Guest VLAN Enabled” checkbox provides a quick way to globally
enable/disable Guest VLAN functionality. When checked, the individual
port settings determine whether the port can be moved into Guest
VLAN. When unchecked, the ability to move to the Guest VLAN is
disabled for all ports.
When Guest VLAN is both globally enabled and enabled 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, and Multi
802.1X