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Optimizing Index Allocation for Sequential Data Broadcasting in Wireless Mobile Computing
January/February 2003 (vol. 15 no. 1)
pp. 161-173
Kun-Lung Wu, IEEE Computer Society

Abstract—Energy saving is one of the most important issues in wireless mobile computing. Among others, one viable approach to achieving energy saving is to use an indexed data organization to broadcast data over wireless channels to mobile units. Using indexed broadcasting, mobile units can be guided to the data of interest efficiently and only need to be actively listening to the broadcasting channel when the relevant information is present. In this paper, we explore the issue of indexing data with skewed access for sequential broadcasting in wireless mobile computing. We first propose methods to build index trees based on access frequencies of data records. To minimize the average cost of index probes, we consider two cases: one for fixed index fanouts and the other for variant index fanouts, and devise algorithms to construct index trees for both cases. We show that the cost of index probes can be minimized not only by employing an imbalanced index tree that is designed in accordance with data access skew, but also by exploiting variant fanouts for index nodes. Note that, even for the same index tree, different broadcasting orders of data records will lead to different average data access times. To address this issue, we develop an algorithm to determine the optimal order for sequential data broadcasting to minimize the average data access time. Performance evaluation on the algorithms proposed is conducted. Examples and remarks are given to illustrate our results.

[1] S. Acharya, R. Alonso, M. Franklin, and S. Zdonik, “Broadcast Disks: Data Management for Asymmetric Communication Environments,” Proc. ACM SIGMOD, pp. 199-210, May 1995.
[2] S. Acharya, M.J. Franklin, and S. Zdonik, Dissemination-Based Data Delivery Using Broadcast Disks IEEE Personal Comm., vol. 2, no. 6, Dec. 1995.
[3] D. Barbara and T. Imielinski, “Sleepers and Workaholics: Caching Strategies in Mobile Environments,” Proc. ACM SIGMOD, pp. 1-12, May 1994.
[4] B. Bruegge and B. Bennington, “Applications of Mobile Computing and Communication,” IEEE Personal Comm., pp. 64-71, Feb. 1996.
[5] J. Cai, “Information Retrieval in a Wireless Mobile Computing Environment.” PhD thesis, 1999.
[6] M. Carey, M. Franklin, M. Livny, and E. Shekita, "Data Caching Tradeoffs in Client-Server DBMS Architecture," Proc. ACM-SIGMOD Conf. Management of Data,Denver, Colo., May 1991.
[7] M.-S. Chen, P.S. Yu, and T.-H. Yang, “On Coupling Multiple Systems with A Global Buffer,” IEEE Trans. Knowledge and Data Eng., vol. 8, no. 2, pp. 339-344, Apr. 1996.
[8] A. Dan, D.M. Dias, and P.S. Yu, “The Effect of Skewed Data Access on Buffer Hits and Data Contention in a Data Sharing Environment,” Proc. 16th Very Large Databases Conf., pp. 419-431, Aug. 1990.
[9] A. Datta, A. Celik, J. Kim, D. VanderMeet, and V. Kumar, “Adaptive Broadcast Protocols to Support Power Conservant Retrieval by Mobile Users,” Proc. 13th Int'l Conf. Data Eng., pp. 124-133, Apr. 1997.
[10] A. Elmagarmid, J. Jain, and T. Furukawa, “Wireless Client/Server Computing for Personal Information Services and Applications,” ACM SIGMOD RECORD, vol. 24, no. 4, pp. 16-21, Dec. 1995.
[11] M.R. Garey and D.S. Johnson, Computers and Intractability: A Guide to the Theory of NP-Completeness.New York: W.H. Freeman, 1979.
[12] D.J. Goodman, “Trends in Cellular and Cordless Communications,” IEEE Comm. Magazine, June 1991.
[13] J. Gray, P. Sundaresan, S. Englert, K. Baclawski, and P.J. Weinberger, “Quickly Generating Billion-Record Synthetic Databases,” Proc. ACM SIGMOD, pp. 243-252, Mar. 1994.
[14] P. Honeyman and L.B. Huston, “Communications and Consistency in Mobile File Systems,” IEEE Personal Comm., Dec. 1995.
[15] Q. Hu, D. Lee, and W.-C. Lee, “Optimal Channel Allocation for Data Dissemination in Mobile Computing Environments,” Proc. 18th IEEE Int'l Conf. Distributed Computing Systems, pp. 480-487, 1998.
[16] Q. Hu, W.-C. Lee, and D. Lee, “Indexing Techniques for Wireless Data Broadcast under Data Clustering and Scheduling,” Proc. Eighth Int'l Conf. Information and Knowledge Management, pp. 351-358, Nov. 1999.
[17] J.-L. Huang, W.-C. Peng, and M.-S. Chen, “Binary Interpolation Search for Solution Mapping on Broadcast and On-Demand Channels in a Mobile Computing Environment,” Proc. 10th ACM Int'l Conf. Knowledge Management, Nov. 2001.
[18] Y. Huang, P. Sistla, and O. Wolfson, "Data Replication for Mobile Computers," Proc. ACM-SIGMOD Int'l Conf. Management of Data,Minneapolis, Minn., May 1994.
[19] T. Imielinski and B.R. Badrinath, “Querying in Highly Mobile and Distributed Environment,” Proc. 18th Int'l Conf. Vary Large Data Bases, pp. 41-52, Aug. 1992.
[20] T. Imielinski and B.R. Badrinath, “Wireless Computing: Challenges in Data Management,” Comm. ACM, vol. 37, no. 10, Oct. 1994.
[21] T. Imielinski, S. Viswanathan, and B.R. Badrinath, Data on Air: Organization and Access IEEE Trans. Knowledge and Data Eng., vol. 9, no. 9, pp. 353-372, June 1997.
[22] D.E. Knuth, The Art of Computer Programming, vol. 1,Addison Wesley, second ed. 1973.
[23] S.-C. Lo and A.L.P. Chen, Optimal Index and Data Allocation in Multiple Broadcast Channels Proc. 16th Int'l Conf. Data Eng., pp. 293-702, Mar. 2000.
[24] J.R. Lorch and A.J. Smith, “Software Strategies for Portable Computer Engergy Management,” IEEE Personal Comm., vol. 5, no. 3, June 1998.
[25] W.-C. Peng and M.-S. Chen, “Dynamic Generation of Data Broadcasting Programs for a Broadcast Disk Array in a Mobile Computing Environment,” Proc. Ninth ACM Int'l Conf. Knowledge Management, pp. 38-45, Nov. 2000.
[26] W.-C. Peng and M.-S. Chen, “Developing Data Allocation Schemes by Incremental Mining of User Moving Patterns in a Mobile Computing System,” IEEE Trans. Knowledge and Data Eng., 2002.
[27] E. Pitoura and G. Samaras, Data Management for Mobile Computing. Kluwer Academic, 1997.
[28] S. Sheng, A. Chandrasekaran, and R.W. Broderson, “A Portable Multimedia Terminal for Personal Communications,” IEEE Comm. Magazine, pp. 64-75, Dec. 1992.
[29] P.A. Sistla, O. Wolfson, S. Chamberlain, and S. Dao, Modeling and Querying Moving Objects Proc. Int'l Conf. Data Eng., pp. 422-432, 1997.
[30] K.-L. Tan and B.-C. Ooi, Data Dissemination in Wireless Computing Environments. Kluwer Academic, 2000.
[31] O. Wolfson, S. Jajodia, and Y. Huang, “An Adaptive Data Replication Algorithm,” ACM Trans. Database Systems, vol. 22, no. 4, pp. 255-314, June 1997.
[32] O. Wolfson and A. Milo, "The Multicast Policy and Its Relationship to Replicated Data Placement," ACM Trans. Database Systems, vol. 16, no. 1, 1991.
[33] K.L. Wu, P.S. Yu, and M.S. Chen, “Energy-Efficient Caching for Wireless Mobile Computing, Proc. 20th Int'l Conf. Data Eng., pp. 336-345, Mar. 1996.

Index Terms:
Wireless mobile computing, energy saving, indexing, sequential broadcasting.
Citation:
Ming-Syan Chen, Kun-Lung Wu, Philip S. Yu, "Optimizing Index Allocation for Sequential Data Broadcasting in Wireless Mobile Computing," IEEE Transactions on Knowledge and Data Engineering, vol. 15, no. 1, pp. 161-173, Jan.-Feb. 2003, doi:10.1109/TKDE.2003.1161588
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