RFC 5266 MIPv 4 and

Enterprise users require mobility and secure connectivity when they roam and connect to the services offered in the enterprise. Secure connectivity is required when the user connects to the enterprise from an untrusted network. Mobility is beneficial when the user moves, either inside or outside the enterprise network, and acquires a new IP address. This document describes a solution using Mobile IPv4 (MIPv4) and mobility extensions to IKEv2 (MOBIKE) to provide secure connectivity and mobility.