Real-Time Hybrid Broadcasting Algorithm Considering Data Property in Mobile Computing Environments

이동 컴퓨팅 환경에서 데이타 특성을 고려한 실시간 혼성 방송 알고리즘

  • 윤혜숙 (특허청 전기전자심사국) ;
  • 김영국 (충남대학교 전기정보통신부)
  • Published : 2005.06.01

Abstract

For recent years, data broadcast technology has been recognized as a very effective data delivery mechanism in mobile computing environment with a large number of cli;ents. Especially, a hybrid broadcast algorithm in real-time environment, which integrates one-way broadcast and on-demand broadcast, has an advantage of adapting the requests of clients to a limited up-link bandwidth and following the change of data access pattern. However, previous hybrid broadcasting algorithms has a problem in the methods to get a grip on the change of data access Pattern. It is caused by the diminution of requests for the data items which are contained in periodic broadcasting schedule because they are already broadcasted. To solve this problem, existing researches may remove data items in periodic broadcasting schedule over a few cycles multiplying cooling factor or find out the requests of data items with extracting them on purpose. Both of them are the artificial methods not considering the property of data. In this paper, we propose a real-time adaptive hybrid broadcasting based on data type(RTAHB-DT) to broadcast considering data property and analysis the performance of our aigorithm through simulation study.

최근 수년 동안, 데이타 방송기술은 많은 수의 클라이언트를 갖는 이동 컴퓨팅 환경에서 매우 효과적인 데이타 전달 시스템으로 주목받고 있다. 특히 흔성 방송은 주기적인 반복 데이타 방송과 온디멘드 방송을 통해, 제한된 대역폭 상에서 많은 이동 클라이언트를 수용하면서 동시에 동적인 데이타 액세스를 지원할 수 있다. 그러나 기존의 흔성 방송 알고리즘에서 데이타 액세스 변화를 파악하기 위해 사용하는 기법에는 문제가 있다. 즉, 많은 요청을 받은 데이타 아이템을 반복 방송에 추가시키면 액세스 요구가 적어져 이 데이타 아이템이 방송되고 있기 때문에 요청이 적어진 것인지 아니면 수요가 줄어서 요청이 적어진 것인지 모른다는 것이다. 기존 연구에서는 이 문제 때문에 냉각값을 곱해 서서히 제거하는 방법을 사용하거나 일부러 방송에서 누락시켜 수요를 창출하는 방법을 사용한다. 그러나 이 두 방법은 모두 데이타의 특성을 고려하지 않는 인공적인 기법이다. 본 논문에서 이러한 문제를 해결하기 위해 데이타 유형을 분류하여 방송하는 데이타 방송 알고리즘 RTAHB-DT(Real-Time Adaptive Hybrid Broadcasting based on Data Type)를 제안하고, 시뮬레이션을 사용해 제안 알고리즘의 성능을 분석한다.

Keywords

References

  1. S. Acharya, R. Alonso, M. Franklin and S. Zdonik, 'Broadcast Disks: Data Management for Asymmetric Communication Environments' in Proceedings of ACM SIGMOD, pp. 199-210, 1995 https://doi.org/10.1145/223784.223816
  2. D. Babrbara, 'Mobile Computing and Database A Survey,' IEEE Trans. Knowledge and Data Eng., vol. 11, no. 1, pp. 108-117, January-Febulary, 1999 https://doi.org/10.1109/69.755619
  3. T. Imielinski, et al. 'Data on Air: Organization and Access,' IEEE TKDE, 9(3): pp. 353-372, 1997 https://doi.org/10.1109/69.599926
  4. S. Acharya, M. Franklin, S. Zdonik, 'Balancing Push and Pull for Data Broadcast' in Proceedings of ACM SIGMOD, Tucson, Arizona, pp. 183-194, May 1997 https://doi.org/10.1145/253262.253293
  5. J. Fernandez and K. Ramamritham, 'Adaptive Dissemination of Data in Time-Critical Asymmetric Communication Environments,' Proceedings of the 11th Euromicro Conference on Real-Time Systems, pp. 491-505 Sep. 1998 https://doi.org/10.1109/EMRTS.1999.777466
  6. K. Stathatos, N. Roussopoulos and J.S. Baras, 'Adaptive Data Broadcast in Hybrid Networks,' 23rd International Conference on Very Large DataBases, Athens, Greece, pp. 326-335, Sept. 1997
  7. C. Hu and M. Chen, 'Adaptive Information Dissemination: An Extended Wireless Data Broadcasting Scheme with Loan-Based Feedback Control,' IEEE Transactions on Mobile Computing, vol 2, No.4, pp. 322-336, October-December, 2003 https://doi.org/10.1109/TMC.2003.1255647
  8. C. Hu an M. Chen, 'Dynamic Data Broadcasting with Traffic Awareness,' Proc. 22nd IEEE Int'l Conf. Distributed· Computing Systems, pp. 112-122, July 2002 https://doi.org/10.1109/ICDCS.2002.1022248
  9. E. Pitoura, 'Supporting Read-Only Transactions in Wireless Broadcasting' in Proceedings of the DEXA '98 Workshop on Mobility in Databases and Distributed Systems, pp. 428-433, August 1998 https://doi.org/10.1109/DEXA.1998.707435
  10. D. Aksoy & M. Franklin, 'Rxw: A scheduling approach for large-scale on-demand broadcast,' ACM/IEEE Transactions on Networking. 846-860, July 1999 https://doi.org/10.1109/90.811450
  11. P. Xuan, S. Sen, OGonzalez, J. Fernandez and K. Ramamritham, 'Efficient and Timely Dissemination of Data in mobile Environments,' Proceedings of the Third IEEE Real Time Technology and Applications Symposium, Montreal Canada, pp. 38-48, June 1997 https://doi.org/10.1109/RTTAS.1997.601342
  12. M. Karakaya, O. Ulusoy, 'An Efficient Broadcast Scheduling Algorithm for Pull-Based Mobile Environments,' Wireless Networks, Vol5(No 3), pp. 183-193 May 1999 https://doi.org/10.1023/A:1019194826654
  13. S. Baruah and S. Lin, 'Pfair Scheduling of Generalized Pinwheel Task Systems,' IEEE Transactions on Computers Vol 47(No 7), pp. 812-816, July 1998 https://doi.org/10.1109/12.709381