Address Resolution Protocol (ARP) is a fundamental Layer 2 protocol that maps IP addresses to MAC addresses within local network segments, enabling communication between devices on the same subnet. It maintains an ARP table (cache) of IP-to-MAC address mappings and includes security features like ARP inspection to prevent ARP spoofing attacks. Additional ARP features include configurable timeouts, proxy ARP for inter-subnet communication, and inspection filters to enhance network security and performance.
By configuring ARP parameters, including inspection, validation, and filters, network administrators can enhance network security, prevent spoofing attacks, and ensure efficient address resolution. These configurations are crucial for maintaining the integrity of local network segments.
You can use these ARP parameters to define precise address resolution behavior and security policies for your network devices. Customize the timeouts, validation rules, and inspection filters to fit your network’s security and operational needs. Adjusting these parameters lets you tailor ARP control for your environment.
The following configuration describes how to set up ARP inspection and related parameters on an IOS-XE device. It lists how to define validation rules, logging, and inspection filters.
ip arp inspection vlan 10,20-30
ip arp inspection validate src-mac dst-mac ip
ip arp inspection log-buffer entries 512
ip arp inspection log-buffer logs 100 interval 300
ip arp inspection filter TRUSTED_HOSTS vlan 20-30
ip arp inspection filter TRUSTED_HOSTS vlan 10 static
ip arp inspection filter GUEST_NETWORK vlan 100-110