TRENDnet TL2-FG142, Руководство пользователя

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TRENDnet User’s Guide
TL2-FG142
22
The Aging Period can be set to a number between 10 and 10,000,000
seconds.
To understand why aging may be desired, consider the following
scenario: Suppose an end-host is connected to a 3rd party switch or hub,
which in turn is connected to a port on this switch on which Limit
Control is enabled. The end-host will be allowed to forward if the limit is
not exceeded. Now suppose that the end-host logs off or powers down.
If it wasn't for aging, the end-host would still take up resources on this
switch and will be allowed to forward. To overcome this situation,
enable aging. With aging enabled, a timer is started once the end-host
gets secured. When the timer expires, the switch starts looking for
frames from the end-host, and if such frames are not seen within the
next Aging Period, the end-host is assumed to be disconnected, and the
correspon
Port Configuration
The table has one row for each port on the switch and a number of columns, which are:
Items Description
Port The port number to which the configuration below applies.
Mode Controls whether Limit Control is enabled on this port. Both this and the
Global Mode must be set to Enabled for Limit Control to be in effect.
Notice that other modules may still use the underlying port security
features without enabling Limit Control on a given port.
Limit The maximum number of MAC addresses that can be secured on this
port. This number cannot exceed 1024. If the limit is exceeded, the
corresponding action is taken.
The switch is "born" with a total number of MAC addresses from which
all ports draw whenever a new MAC address is seen on a Port Security-
enabled port. Since all ports draw from the same pool, it may happen
that a configured maximum cannot be granted, if the remaining ports
have already used all available MAC addresses.
Action If Limit is reached, the switch can take one of the following actions:
None: Do not allow more than Limit MAC addresses on the port, but
take no further action.
Trap: If Limit + 1 MAC addresses is seen on the port, send an SNMP trap.
If Aging is disabled, only one SNMP trap will be sent, but with Aging
enabled, new SNMP traps will be sent every time the limit gets
exceeded.
Shutdown: If Limit + 1 MAC addresses is seen on the port, shut down the
port. This implies that all secured MAC addresses will be removed from
the port, and no new address will be learned. Even if the link is physically
disconnected and reconnected on the port (by disconnecting the cable),
the port will remain shut down. There are three ways to re-open the
port:
1) Boot the switch,
2) Disable and re-enable Limit Control on the port or the switch,
3) Click the Reopen button.
Trap & Shutdown: If Limit + 1 MAC addresses is seen on the port, both
the "Trap" and the "Shutdown" actions described above will be taken.
State This column shows the current state of the port as seen from the Limit
Control's point of view. The state takes one of four values:
Disabled: Limit Control is either globally disabled or disabled on the port.
Ready: The limit is not yet reached. This can be shown for all actions.
Limit Reached: Indicates that the limit is reached on this port. This state
can only be shown if Action is set to None or Trap.
Shutdown: Indicates that the port is shut down by the Limit Control
module. This state can only be shown if Action is set to Shutdown or
Trap & Shutdown.
Re-open
Button If a port is shutdown by this module, you may reopen it by clicking this
button, which will only be enabled if this is the case. For other methods,
refer to Shutdown in the Action section.
Note that clicking the reopen button causes the page to be refreshed, so
non-committed changes will be lost.
4.3.5.8NAS
This page allows you to configure the IEEE 802.1X and MAC-based authentication
system and port settings.