Neighbor discovery (ND) is an ICMPv6 function that enables a node to identify other hosts and routers on its links. It corresponds to a combination of IPv4 protocols:

• ARP
• ICMP Router Discovery
• ICMP Redirect

It maintains routes, MTU, retransmit times, reachability time, and prefix information based on information received from the routers. ND uses duplicate address detection (DAD) to verify the host's home addresses are unique on the LAN.