Unlike ARP in previous versions of Windows, ARP in Windows Server 2008 and Windows Vista is designed to work in the same way as Neighbor Discovery in IP version 6 (IPv6), as described in RFC 4861. Neighbor Discovery in IPv6 is the replacement for ARP, router discovery, and the redirect function in IP version 4 (IPv4). IPv6 nodes use a neighbor cache to store the MAC addresses of recently resolved IPv6 addresses, rather than an ARP cache. Neighbor Discovery in IPv6 also provides additional capabilities that are not present in IPv4, such as neighbor unreachability detection.
The following sections describe how ARP in Windows Server 2008 and Windows Vista works for the following processes: