HP-UX IPv6 Transport Administrator's Guide for TOUR 2.0 (April 2004, rev 2)

IPv6 Addressing and Concepts
Neighbor Discovery
Chapter 6 59
Neighbor Discovery
IPv6 hosts and routers use the IPv6 Neighbor Discovery Protocol to:
• advertise their link-layer address on the local link
• find neighbors’ link-layer addresses on the local link
• find neighboring routers able to forward IPv6 packets
• actively track which neighbors are reachable
• search for alternate routers when a path to a router fails
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).”