IPv6 Stateless Address Autoconfiguration
S. Thomson, T. Narten, T. Jinmei · 2007-09
Abstract
RFC 4862 defines IPv6 Stateless Address Autoconfiguration (SLAAC), a mechanism that allows IPv6 hosts to automatically configure their own globally routable addresses without a DHCP server. Hosts derive addresses from router-advertised prefixes combined with an interface identifier, and validate uniqueness using Duplicate Address Detection.
Why This RFC Matters
SLAAC represents a fundamental rethinking of how hosts get IP addresses. In the IPv4 world, DHCP servers are essential infrastructure — without them, hosts cannot communicate. IPv6's SLAAC allows any host to self-configure a globally routable address the moment a router advertises a prefix, with no central server required. This dramatically simplifies network provisioning and enables 'plug-and-play' IPv6 connectivity. SLAAC also introduced privacy extensions (RFC 4941) to generate randomized interface identifiers, preventing the MAC-address-based tracking that early SLAAC implementations enabled. The mechanism defined in RFC 4862 is now fundamental to how billions of devices join IPv6 networks.