On providing seamless handoff in ad hoc networks with wireless heterogeneity

In our papers for MILCOM 2006 and 2007, we have presented an integrated architecture for seamless soft handoff in mobile ad hoc networks and demonstrated the good performance via showing that our handoff scheme can provide equivalent results as the benchmark with no handoff. In this position paper, we aim to investigate the general handoff problem in face of multiple heterogeneous wireless interfaces and non-trivial node mobility. This becomes ever important, since wireless heterogeneity will persist and nodes in military ad hoc networks are bound to move beyond rare-and-slow scenarios. The combination of wireless heterogeneity and mobility incurs lots of challenges in research and development, and the ultimate goal in our research is to provide transparent and seamless user experience in such environments without fixed or predictable infrastructure support. This paper identifies such challenges across the stack, investigates the design space, and points out promising research avenues. Finally, we investigate how such ideas may be implemented in the integrated architecture, which also contains the IEEE 802.21 Media Independent Handover functionality as a supporting component.