This document defines mobility and multihoming extensions to the Host
Identity Protocol (HIP). Specifically, this document defines a
general "LOCATOR" parameter for HIP messages that allows for a HIP
host to notify peers about alternate addresses at which it may be
reached. This document also defines elements of procedure for
mobility of a HIP host -- the process by which a host dynamically
changes the primary locator that it uses to receive packets. While
the same LOCATOR parameter can also be used to support end-host
multihoming, detailed procedures are left for further study. This memo defines
an Experimental Protocol for the Internet community.