While I have studied ARP, I don’t have a page on it yet. Coming soon!

Address Resolution Protocol (ARP)

A communication protocol used for discovering the MAC address of unknown devices. When a device needs to forward traffic to an IP for which it has no associated MAC address in its address table, it will broadcast an ARP Request message containing it’s IP and the IP of the device whose MAC it is trying to find. Only the correct recipient device will unicast an ARP Reply to the source device.

Address Resolution Protocol (ARP),

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ARP is not used in IPv6. See its successor Neighbor Discovery Protocol (NDP) for more information.

Gratuitous ARP

ARP replies sent without being requested (no ARP request message was received).

Frames are broadcast to FFFF.FFFF.FFFF (normal ARP replies are unicast)