Address Resolution Protocol

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Related to Address Resolution Protocol: Reverse Address Resolution Protocol

Address Resolution Protocol

(networking, protocol)
(ARP) A method for finding a host's Ethernet address from its Internet address. The sender broadcasts an ARP packet containing the Internet address of another host and waits for it (or some other host) to send back its Ethernet address. Each host maintains a cache of address translations to reduce delay and loading. ARP allows the Internet address to be independent of the Ethernet address but it only works if all hosts support it.

ARP is defined in RFC 826.

The alternative for hosts that do not do ARP is constant mapping.

See also proxy ARP, reverse ARP.
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(Address Resolution Protocol) A TCP/IP protocol used to obtain a node's physical address in the traditional IP addressing system (see IPv4). A client station broadcasts an ARP request onto the network with the IP address of the target node it wishes to communicate with, and the node with that IP address responds by sending back its physical MAC address so that packets can be transmitted. ARP returns the layer 2 address for a layer 3 address. See NDP, ARP cache, ARP cache poisoning, RARP and TCP/IP abc's.

The IP protocol broadcasts the IP address of the destination station onto the network, and the node with that address responds.
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References in periodicals archive ?
Additionally, a rich suite of security features including IP source guard, dynamic Address Resolution Protocol (ARP) inspection and DHCP snooping shield the enterprise from internal and external threats.
ARP -- Address Resolution Protocol: provides the low level message services, which allows a NIC to join a network.