Planet IGS-5225 Series User Manual page 352

• Aging Period
• Hold Time
Port Configuration
The table has one row for each port and a number of columns, which are:
Object
• Port
• Mode
• Limit
If Aging Enabled is checked, then the aging period is controlled with this input. If
other modules are using the underlying port security for securing MAC
addresses, they may have other requirements to the aging period. The
underlying port security will use the shorter requested aging period of all modules
that use the functionality.
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 corresponding
resources are freed on the switch.
The hold time - measured in seconds - is used to determine how long a MAC
address is held in the MAC table if it has been found to violate the limit. Valid
range is between 10 and 10000000 seconds with a default of 300 seconds.
The reason for holding a violating MAC address in the MAC table is primarily to
ensure that the same MAC address doesn't give rise to continuous notifications
(if notifications on violation count is enabled).
Description
The port number for which the configuration below applies.
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.
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
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User's Manual of IGS-5225 series