A profile-based hierarchical location management scheme for future PCS

To accommodate the growth in the user population and network size in mobile environments, hierarchical architectures of location databases have been proposed. Recent studies showed that the signaling traffic and processing overhead of location updates is expected to grow tremendously, leading to poor performance. The authors present a Profile based Hierarchical location management Scheme (PHS) that focuses on reducing the cost of updates while keeping the lookup cost low. Our proposal is motivated by the observation that users follow repetitive patterns that can be profiled and predicted with reasonable cost, allowing users to send updates occasionally and not on every move. Further, it deploys a simple prediction technique that reduces the uncertainty of a user´s location. We quantify the costs and benefits of PHS for several mobility patterns and show that it can result in up to 60% reduction in the update cost with minimal increase (7%) in lookup cost