Explains how ARP maps IP addresses to MAC addresses, how address resolution operates on local and routed networks, and which restrictions apply to ARP configuration.
Address Resolution Protocol (ARP) is an address-mapping protocol that
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takes an IP address as input and determines its associated media or MAC address
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stores the IP-to-MAC address association in an ARP cache for rapid retrieval, and
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enables an IP datagram to be encapsulated in a link-layer frame and sent over the network.
Cisco IOS XR software supports ARP, proxy ARP, and local proxy ARP. ARP is defined in RFC 826, and proxy ARP is defined in RFC 1027.
The system typically resolves addresses dynamically. You can also configure a static ARP entry when a permanent mapping is required.