D-Link DWS-3160-24TC Reference Manual page 217

DWS-3160 Series Gigabit Ethernet Unified Switch Web UI Reference Guide
The fields that can be configured are described below:
Parameter
From Port / To Port
ARP Inspection
IP Inspection
Protocol
Zero IP
DHCP Packet
Stop Learning
Threshold
Click the Apply button to accept the changes made.
Figure 11-27 IMPB Port Settings window
Description
Select a range of ports to set for IP-MAC-port binding.
When the ARP inspection function is enabled, the legal ARP packets are forwarded,
while the illegal packets are dropped.
Disabled - Disable the ARP inspection function.
Enabled (Strict) - This mode disables hardware learning of the MAC address. All
packets are dropped by default until a legal ARP or IP packets are detected. When
enabling this mode, the Switch stops writing dropped FDB entries on these ports. If
detecting legal packets, the Switch needs to write forward FDB entry.
Enabled (Loose) - In this mode, all packets are forwarded by default until an illegal
ARP packet is detected.
The default value is Disabled.
When both ARP and IP inspections are enabled, all IP packets are checked. The
legal IP packets are forwarded, while the illegal IP packets are dropped. When IP
Inspection is enabled, and ARP Inspection is disabled, all non-IP packets (Ex. L2
packets, or ARP) are forwarded by default.
The default value is Disabled.
Use the drop-down menu to select the protocol.
Use the drop-down menu to enable or disable this feature. Allow zero IP configures
the state which allows ARP packets with 0.0.0.0 source IP to bypass.
By default, the DHCP packet with broadcast DA will be flooded. When set to disable,
the broadcast DHCP packet received by the specified port will not be forwarded in
strict mode. This setting is effective when DHCP snooping is enabled, in the case
when a DHCP packet which has been trapped by the CPU needs to be forwarded by
the software. This setting controls the forwarding behavior in this situation.
Here is displayed the number of blocked entries on the port. The default value is 500.
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