Increased research and development in the field of ubiquitous computing, and in particular smart spaces, has heightened the need for a comprehensive mobility solution. Existing mobility protocols are often categorised as either macro or micro mobility but few, if any, bridge the divide between the two. Mobile IP is at present the IETF proposed standard for delivery of IP packets to mobile devices. However, as a macro mobility protocol, it does not adequately support data delivery to mobile devices that regularly roam within local networks. Cellular IP, a more recent development in mobility, falls under the banner of micro mobility and as such delivers a number of benefits that a macro mobility protocol alone could not. This paper describes a complete mobility architecture accomplished by integrating Mobile IP with Cellular IP and continues by addressing the suitability of this integration for supporting roaming in smart environments
