IPv4 deployments use one of two methods to
assign IP addresses to a host: static assignment
(which is management-intensive) or DHCP/
BOOTP, which automatically assigns IP addresses
to hosts upon booting onto the network.
IPv6 provides a feature called stateless autoconfiguration,
which is similar to DHCP. Unlike DHCP,
however, stateless autoconfiguration does not
require the use of a special DHCP application or
server when providing addresses to simple network
devices that do not support DHCP (such as robotic
arms used in manufacturing).
Using DHCP, any router interface that has an IPv6
address assigned to it becomes the “provider” of IP
addresses on the network to which it is attached.
Safeguards are built into IPv6 that prevent duplicate
addresses. This feature is called Duplicate
Address Detection. With the IPv4 protocol, nothing
prevents two hosts from joining the network
with identical IP addresses. The operating system
or application may be able to detect the problem,
but often unpredictable results occur.