Arp Inspection Trusted Interface Settings; Figure 3-85. Arp Inspection Properties Page - Alcatel OS-LS-6224 User Manual

Figure 3-85. ARP Inspection Properties Page

ARP Inspection Trusted Interface Settings

The ARP Inspection Trusted Interface Page allows network managers to define
trusted and untrusted interfaces (independent of the trusted interface settings
defined for DHCP snooping). ARP Inspection can be enabled only on untrusted
interfaces.
• Trusted — Indicates that the interface IP and MAC address are recognized, and
recorded in the ARP Inspection List. Trusted packets are forward without ARP
Inspection.
• Untrusted — Indicates that the packet arrived from an interface that does not have
a recognized IP and MAC addresses. The packet is checked for:
– Source MAC — Compares the packet's source MAC address against the
sender's MAC address in the ARP request. This check is performed on
both ARP requests and responses.
– Destination MAC — Compares the packet's destination MAC address
against the destination interface's MAC address. This check is performed
for ARP responses.
– IP Addresses — Compares the ARP body for invalid and unexpected IP
addresses. Addresses include 0.0.0.0, 255.255.255.255, and all IP
Multicast addresses. If the packet's IP address was not found in the ARP
Inspection List, and DHCP snooping is enabled for a VLAN, a search of
the DHCP Snooping Database is performed. If the IP address is found the
packet is valid, and is forwarded.
Dynamic ARP Inspection
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