Stateless auto configuration (SLAAC)
SLAAC is preferred over DHCPv6 for simple setups. It also replaces ARP for discovering layer 2 addresses given an IP. It is based on a new set of ICMPv6 message Neighbor Discovery and Router Advertisement types.
The advantage of this method is that it requires no dedicated server for keeping state (although each node has to get smarter to handle solicitations/advertisements).