Enabling Intelligent Handovers in Heterogeneous Wireless Networks

摘要

In the future Wireless Internet, mobile nodes will be able to choose between providers offering competing services at a much finer granularity than we find today. Rather than months, service contracts may span hours or minutes. Connectivity, however, is just one of many possible services. Providers will begin to offer network and application-level services targeted at improving the overall wireless experience of the user. Determining the best path through the various networks will require accurate information describing which services are being offered by each provider. In this paper, we model the process of propagating this information as an instance of a distributed, hierarchical cache. Access routers actively discover and collect information about the immediate network neighborhood on behalf of mobile nodes. Mobiles fill their own caches through queries to their local access routers, and then employ the cached information to make informed, intelligent handover decisions. Through simulation, we show that high cache hit rates at the mobile node can be achieved even when the discovery process at the access router is incomplete. In comparison to static and centralized approaches, our dynamic approach requires less configuration and maintenance, avoids single points of failure, and provides a scalable solution that spans administrative domains.