ZyXEL Communications VES1724-56 User Manual page 192

Chapter 19 MAC Limit
For maximum port security, enable this feature, disable MAC address learning and
Note:
configure static MAC address(es) for a port. It is not recommended you disable
Port Security together with MAC address learning as this will result in many
broadcasts.
Figure 112 MAC Limit: Port Security
The following table describes the labels shown after you select the Port Security in this screen.
Table 74 MAC Limit: Port Security
LABEL
Port
*
Active
Address
Learning
Limited Number
of Learned MAC
Address
192
DESCRIPTION
This field displays a port number.
Settings in this row apply to all ports.
Use this row only if you want to make some settings the same for all ports. Use this row first
to set the common settings and then make adjustments on a port-by-port basis.
Note: Changes in this row are copied to all the ports as soon as you make them.
Select this check box to enable the port security feature on this port. The switch forwards
packets whose MAC address(es) is in the MAC address table on this port. Packets with no
matching MAC address(es) are dropped.
Clear this check box to disable the port security feature. The switch forwards all packets on
this port.
MAC address learning reduces outgoing broadcast traffic. For MAC address learning to occur
on a port, the port itself must be active with address learning enabled.
Use this field to limit the number of (dynamic) MAC addresses learned on a port. For
example, if you set this field to "5" on port 2, then only the devices with the first five learned
MAC addresses can access port 2 at any one time. A sixth device would have to wait until
one of the five learned MAC addresses aged out. MAC address aging time can be set in the
Basic Setting > Switch Setup screen.
The valid range is from 0 to 16K (16384 bytes). "0" means this feature is disabled, so the
switch will learn MAC addresses up to the global limit of 16K.
VES1724-56 User's Guide