Mobile IPv4 Regional Registration

Using Mobile IP, a mobile node registers with its home agent each time it changes care-of address. This document describes a new kind of "regional registrations", i.e., registrations local to the visited domain. The regional registrations are performed via a new network entity called a Gateway Foreign Agent (GFA) and introduce a layer of hierarchy in the visited domain. Regional registrations reduce the number of signaling messages to the home network, and reduce the signaling delay when a mobile node moves from one foreign agent to another within the same visited domain. This document is an optional extension to the Mobile IPv4 protocol. This memo defines an Experimental Protocol for the Internet community.