Digital Equipment Corporation This document describes a mechanism that can be used by IPv6 hosts to communicate information about their address configuration to neighboring routers. In particular, this mechanism is intended to allow multihomed hosts and hosts with anycast addresses to communicate this information to their neighboring routers. This document defines a new ICMPv6 informational message type, a 'Host Reachability Advertisement' to carry this information. It also defines a second ICMPv6 message, a 'Host Reachability Solicitation', that can be used to trigger Host Reachability Advertisements.