Neighbor Discovery

IPv6 hosts and routers use the IPv6 Neighbor Discovery Protocol to:

The IPv6 Neighbor Discovery Protocol (ndp) uses ICMPv6. An IPv6-only utility, ndp and the Neighbor Discovery Protocol encompass the functionality of the IPv4 Address Resolution Protocol (ARP) and the arp utility. ndp also provides some of the address-configuration functionality found in protocols BOOTP and DHCP.

A network device connecting to a network for the first time can learn all parameters necessary to function, solely through Neighbor Discovery information. Both IPv6 hosts and routers advertise their presence using neighbor advertisements and route advertisements, respectively. When an IPv6 host first comes up, it advertises its link-layer address, and solicits neighbor and router information.

For more information, see the ndp(1m) and ndp(7p) man pages and RFC 2461, “Neighbor Discovery for IP Version 6 (IPv6).”