DOI QR코드

DOI QR Code

The Comparison of RBS and TDP for the Sensor Networks Synchronization

  • Lee, Hyo-Jung (Department of Information and Communications Engineering, Chungnam National University) ;
  • Kim, Byung-Chul (Department of Information and Communications Engineering, Chungnam National University) ;
  • Kwon, Young-Mi (Department of Information and Communications Engineering, Chungnam National University)
  • Published : 2005.12.01

Abstract

Sensor networks have emerged as an interesting and important research area in the last few years. These networks require that time be synchronized more precisely than in traditional Internet applications. In this paper, we compared and analyzed the performance of the RBS and TDP mechanisms in the view of the number of generated messages and the synchronization accuracy. The reason that we chose be RBS ad the TDP mechanism to be compared is because the RES is an innovative method to achieve the high accurate synchronization. And TDP is a new method taking over the NTP method which has been used widely in the Internet. We simulated the performance of two methods assuming the IEEE 802.11 CSMA/CA MAC. As for the number of nodes in the sensor networks, two situations of 25 (for the small size network) and 100 (for the large size network) nodes are used. In the aspect of the number of messages generated for the synchronization, TDP is far better than RBS. But, the synchronization accuracy of RBS is far higher than that of TDP. We cm conclude that in a small size sensor networks requiring very high accuracy, such as an application of very high speed objects tracking in a confined space, the RBS is more proper than TDP even though the RBS may generate more traffic than TDP. But, in a wide range sensor networks with a large number of nodes, TDP is more realistic though the accuracy is somewhat worse than RBS because RBS may make so many synchronization messages, and then consume more energies at each node. So, two mechanisms may be used selectively according to the required environments, without saying that the one method is always better than the other.

Keywords

References

  1. I. F. Akyildiz, W. Su, Y. Sankarasubramaniam, and E. Cayirci. Wireless Sensor Networks: A Survey. Computer Networks, 38(4):393–422, March 2002
  2. Saurabh Ganeriwal, Ram Kumar, Sachin Adlakha and Mani Srivastava, Network-wide Time Synchronization in Sensor Networks, Technical Report UCLA, April 2002
  3. D.L. Mills, Improved Algorithms for Synchronizing Computer Network Clocks, Proc. of ACM SIGCOMM 94 Symposium, September 1994
  4. J. Elson, L. Girod, and D. Estrin, Fine-Grained Network Time Synchronization using Reference Broadcasts, Proceedings of the Fifth Symposium on Operating systems Design and Implementation, Boston, MA. December 2002
  5. W. Su, and I.F. Akyildiz, Time-Diffusion Synchronization Protocol for Sensor Networks, Georgia Tech Technical Report, 2003
  6. Jana van Greunen and Jan Rabaey. Lightweight Time Synchronization for Sensor Networks, WSNA 2003, San Diego, CA September 2003
  7. R. Karp, J. Elson, D. Estrin, and S. Shenker. Optimal and Global Time Synchronization in Sensornets, CENS Technical Report 0012, Center for Embedded Networked Sensing, University of California, April 2003
  8. M.L. Sichitiu, C. Veerarittiphan, Simple, accurate time synchronization for wireless sensor networks, Wireless Communications and Networking, Vol 2, March 2003, Pages: 1266 - 1273