Stateless Autoconfiguration enables IPv6 hosts to send a request for a prefix, a network identifier to a router on the subnet. Using this ability a host can configure its IPv6 address. Likewise, by defining a way to request for a prefix to an upper level router, a router can get a prefix to be assigned to its subnet. This document describes a protocol for prefix delegation between routers. It allows routers get prefixes from its upstream routers, enabling the entire network and its belonging hosts autoconfigure their own addresses.