ZyXEL Communications GS-4024 - Manual (Page 217)

Chapter 24 IP Source Guard
GS-4012F/4024 User’s Guide
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The following table describes the labels in this screen.
24.7.2 ARP Inspection VLAN Configure
Use this screen to enable ARP inspection on each VLAN and to specify when the Switch
generates log messages for receiving ARP packets from each VLAN. To open this screen,
click Advanced Application > IP Source Guard > ARP Inspection > Configure > VLAN.
Figure 112 ARP Inspection VLAN Configure
Table 78 ARP Inspection Port Configure
LABEL DESCRIPTION
Port This field displays the port number. If you configure the * port, the settings
are applied to all of the ports.
Trusted State Select whether this port is a trusted port (Trusted) or an untrusted port
(Untrusted).
The Switch does not discard ARP packets on trusted ports for any reason.
The Switch discards ARP packets on untrusted ports in the following
situations:
•
The sender’s information in the ARP packet does not match any of the
current bindings.
• The rate at which ARP packets arrive is too high. You can specify the
maximum rate at which ARP packets can arrive on untrusted ports.
Limit These settings have no effect on trusted ports.
Rate (pps) Specify the maximum rate (1-2048 packets per second) at which the
Switch receives ARP packets from each port. The Switch discards any
additional ARP packets. Enter 0 to disable this limit.
Burst interval
(seconds) The burst interval is the length of time over which the rate of ARP packets
is monitored for each port. For example, if the Rate is 15 pps and the burst
interval is 1 second, then the Switch accepts a maximum of 15 ARP
packets in every one-second interval. If the burst interval is 5 seconds,
then the Switch accepts a maximum of 75 ARP packets in every five-
second interval.
Enter the length (1-15 seconds) of the burst interval.
Apply Click Apply to save your changes to the Switch’s run-time memory. The
Switch loses these changes if it is turned off or loses power, so use the
Save link on the top navigation panel to save your changes to the non-
volatile memory when you are done configuring.
Cancel Click this to reset the values in this screen to their last-saved values.