IPv6
In the Internet Protocol Version 6 (IPv6), the address block fe80::/10 has been reserved for link-local addressing. The actual link local addresses are assigned with the prefix fe80::/64. They may be assigned by automatic (stateless) or stateful (e.g. manual) mechanisms.
Unlike IPv4, IPv6 requires a link-local address to be assigned to every network interface on which the IPv6 protocol is enabled, even when one or more routable addresses are also assigned. Consequently, IPv6 hosts usually have more than one IPv6 address assigned to each of their IPv6-enabled network interfaces. The link-local address is required for IPv6 sublayer operations of the Neighbor Discovery Protocol, as well as for some other IPv6-based protocols, like DHCPv6.
In IPv6, stateless address autoconfiguration is performed as a component of the Neighbor Discovery Protocol (NDP), as specified in RFC 4862. The address is formed from its routing prefix and the MAC address of the interface.
IPv6 introduced additional means of assigning addresses to host interfaces. Through NDP routing prefix advertisements, a router or a dedicated server host may announce configuration information to all link-attached interfaces which causes additional IP address assignment on the receiving interfaces for local or global routing purposes. This process is sometimes also considered stateless, as the prefix server does not receive or log any individual assignments to hosts. Uniqueness is guaranteed automatically by the address selection methodology (MAC-address based according to RFC 4862, and/or randomized according to RFC 4941) in combination with the duplicate address detection algorithm.
Read more about this topic: Link-local Address