We consider the problem of managing the information required to locate users in a wireless communication system, with a focus on designing and evaluating location management techniques that are efficient, scalable, and flexible. The three key contributions of this paper are: (1) A family of location management techniques, HiPER (for Hierarchical ProfilE Replication), that efficiently provide life-long (non-geographic) numbering with fast location lookup; (2) Pleiades, a scalable event-driven wireless system simulator with realistic calling and mobility patterns derived from several months of real traffic traces; and (3) multi-day simulations comparing our proposed location management techniques with current and previously proposed techniques on a realistic geographical and network topology. Research supported by the Center for Telecommunications and the Center for Integrated Systems at Stanford University, and by equipment grants from Digital and IBM Corporations. 1 Introduction I...

We consider per-user profile replication as a mechanism for faster location lookup of mobile users in a Personal Communications Service system. We present a minimum-cost maximum-flow based algorithm to compute the set of sites at which a user profile should be replicated given known calling and user mobility patterns. We then present schemes for replication plans that gracefully adapt to changes in the calling and mobility patterns. We show the costs and benefits of our replication algorithm against previous location lookup approaches through analysis. We also simulate our algorithm against other location lookup algorithms on a realistic model of a geographical area to evaluate critical system performance measures. A notable aspect of our simulations is that we use well-validated models of user calling and mobility patterns. 1 Introduction In a Personal Communications Service (PCS) system, users place and receive calls through a wireless medium. Calls may deliver voice, data, text, fa...

This paper presents a realistic modeling framework for evaluating the performance of location management schemes in PCS networks. The framework captures complex human behaviors and has been validated through analysis of actual call and mobility data. Simulation results, showing the performance of IS-41, are presented.