Support mobility in the global internet

Today's technology trend indicates that billions of hand-held gadgets as well as other types of mobile devices will be coming online in the next few years. While the existing Internet mobility standards, namely Mobile IP, is waiting for a wide adoption, cellphone networks are providing the ubiquitous mobility services on a global scale as of today. They have also promoted IP core network architecture and adopted Proxy Mobile IPv6, an extension to Mobile IP, for their mobility service. There is an open question regarding whether the Internet would, or would not, require significant architectural changes to provide universal mobility support at a scale that is likely to go far beyond the scale and scope of today's cellular telephone services. In this paper, we examine the fundamental di erences between the mobility service models provided by Internet and cellphone systems. We argue that decoupling network access control from mobility support can provide an architecturally promising direction for scalable and decentralized mobile communications, and that designing mobility support outside the global routing system can o er an overall best tradeo as measured by flexibility, manageability, and scalability of the resulting systems.