Per-User Pro le Replication in Mobile Environments: Algorithms, Analysis, and Simulation Results

We consider per-user pro le replication as a mechanism for faster location lookup of mobile users in a Personal Communications Service system. We present a minimum-cost maximumow based algorithm to compute the set of sites at which a user pro le 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 bene ts 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]  Hanif D. Sherali,et al.  Linear Programming and Network Flows , 1977 .

[2]  Dorit S. Hochbaum,et al.  Database Location in Computer Networks , 1980, JACM.

[3]  Giancarlo Martella,et al.  Optimal File Allocation in a Computer Network: a Solution Method Based on the Knapsack Problem , 1982, Comput. Networks.

[4]  D. Bertsekas The auction algorithm: A distributed relaxation method for the assignment problem , 1988 .

[5]  B. Awerbuch,et al.  Concurrent online tracking of mobile users , 1991, SIGCOMM '91.

[6]  Sushil Jajodia,et al.  Distributed algorithms for dynamic replication of data , 1992, PODS.

[7]  John Zhonghe Wang A Fully Distributed Location Registration Strategy for Universal Personal Communication Systems , 1993, IEEE J. Sel. Areas Commun..

[8]  Ravi Jain,et al.  Two user location strategies for personal communications services , 1994, IEEE Personal Communications.

[9]  Raj Jain,et al.  Analysis and simulation of a cache-based auxiliary user location strategy for PCS , 1994, Proceedings of Networks for Personal Communications - NPC'94.

[10]  Ravi Jain,et al.  A caching strategy to reduce network impacts of PCS , 1994, IEEE J. Sel. Areas Commun..

[11]  Venkat Anantharam,et al.  Optimization of a Database Hierarchy for Mobility Tracking in a Personal Communications Network , 1994, Perform. Evaluation.

[12]  An auxiliary user location strategy employing forwarding pointers to reduce network impacts of PCS , 1995, Wirel. Networks.

[13]  Jennifer Widom,et al.  Data Management for User ProFILEs in Wireless Communication Systems , 1995 .

[14]  Ian F. Akyildiz,et al.  Local anchor scheme for reducing location tracking costs in PCNs , 1995, MobiCom '95.

[15]  Jennifer Widom,et al.  Modeling location management in personal communications services , 1996, Proceedings of ICUPC - 5th International Conference on Universal Personal Communications.

[16]  Xian Zhou,et al.  Locating Strategies for Personal Communication Networks: A Novel Tracking Strategy , 1997, IEEE J. Sel. Areas Commun..