LevelOne GEP-2651 - Port Configuration

Publication date: June, 2015
Revision A1
57
Parameter description:
System Configuration
 Mode :
Indicates if Limit Control is globally enabled or disabled on the switch. If globally disabled,
other modules may still use the underlying functionality, but limit checks and corresponding
actions are disabled.
 Aging Enabled :
If checked, secured MAC addresses are subject to aging as discussed under Aging Period .
 Aging Period :
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.
Port Configuration
The table has one row for each port on the selected switch and a number of columns, which
are:
 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.