Mobile IP extension to ad hoc wireless networks

Mobile IP has been proposed for providing mobility services for mobile nodes that have direct (fixed or wireless) links to the Internet. In this paper, we consider extending Mobile IP to accommodate mobility support for mobile nodes that are two or more wireless hops away from a fixed infrastructure. Our proposal differs from existing solutions in that we do not use ad hoc routing protocols to relay Mobile IP messages and data packets: standard IP routing is used instead. The advantages of our proposal are (1) Mobile IP foreign agents need not be modified. (2) legacy mobile nodes that do not implement the extension are still able to connect to the fixed infrastructure, and (3) mobile nodes behave the same, no matter they have a direct link to the infrastructure or not. The proposed protocol has been implemented and tested.