3Com 5500-EI PWR Install Manual page 566

Enable ARP attack detection based on bindings of authenticated 802.1x clients on the switch to
prevent ARP attacks.
Network Diagram
Figure 2-6 Network diagram for 802.1x based ARP attack defense
Configuration Procedures
# Enter system view.
<Switch> system-view
# Enable 802.1x authentication globally.
[Switch] dot1x
# Enable ARP attack detection for VLAN 1.
[Switch] vlan 1
[Switch-vlan1] arp detection enable
[Switch-vlan1] quit
# Configure Ethernet 1/0/2 and Ethernet 1/0/3 as ARP trusted ports.
[Switch] interface Ethernet 1/0/2
[Switch-Ethernet1/0/2] arp detection trust
[Switch-Ethernet1/0/2] quit
[Switch] interface Ethernet 1/0/3
[Switch-Ethernet1/0/3] arp detection trust
[Switch-Ethernet1/0/3] quit
# Enable ARP attack detection based on IP-to-MAC mappings of authenticated 802.1x clients.
[Switch] ip source static import dot1x
# Enable 802.1x on Ethernet 1/0/1.
[Switch] interface ethernet 1/0/1
[Switch-Ethernet1/0/1] dot1x
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