無線感測器網路是由感測單元、資料處理單元以及溝通單元的大量感測裝置節點(Sensor node)所組成。其中收集點(Sink node)負責收集每個節點所傳來的資料。當多個收集點時，僅以單播傳輸將資料送至收集點時，會消耗大量能源。因此以多播傳輸的方式才能節省能源消耗。
　　本碩士論文提出的多播傳輸協定主要分成三個部份：多播傳輸成本計算、建立多播表、修剪多播表。成本計算則是分析鄰點(One-hop neighbor)、收集點及單播傳輸成本等資訊，推導出多播傳輸成本的計算公式。建立多播表則是利用特殊的多路徑路由表(Multi-path routing table)的路徑資訊，建立出完整的多播傳輸資訊，並記載由成本計算公式所得之結果。修剪多播表部份，則是介紹兩種移除條目的機制，以減低記憶體空間和計算量。經由NS2的網路模擬實驗之後，證明本論文所提出的多播傳輸協定，能夠顯著地降低能源消耗，並達到高資料傳達率。

　　A wireless sensor network is composed of a large number of sensor nodes which consist of sensing, data processing, and communicating components. The sink node is responsible for data collection. It consumed a large amount of energy, that the sender unicasts the data to multiple sink nodes. In order to reduce the energy consumption, the sender should use multicasting mechanism.
　　The multicast protocol proposed by the thesis is consisting of multicasting cost computation, multicasting table building, multicasting table pruning. In multicasting cost computation, the thesis deduced the formulations of multicasting cost. In multicasting table building, the thesis used the information of multi-path routing table to build the complete multicasting information. In multicasting table pruning, the thesis introduced two pruning approaches to reduce the computation complexity and memory requirement. Simulations had been conducted by using NS2 to evaluate the performance. Simulation results confirmed the proposed multicast protocol reduces the energy consumption dramatically, while achieving a high packet delivery rate.

[1] F. Akyildiz, W. Su, Y. Sankarasubramaniam, and E. Cayirci, "A Survey on Sensor Networks," IEEE Communication Magazine, Aug. 2002.
[2] J. N. Al-Karaki, and A. E. Kamal, "Routing techniques in wireless sensor networks: a survey", IEEE Wireless Communications, Dec. 2004.
[3] C. Chiang, M. Gerla, and L. Zhang, "Forwarding Group Multicast Protocol (FGMP) for Multihop, Mobile Wireless Networks," Annual Joint Cluster Computer, Special Issue on Mobile Computing, 1998.
[4] T. V. Dam, and K. Langendoen, "An adaptive energy-efficient MAC protocol for wireless sensor networks," Proc. 1st International Conference on Embedded Networked Sensor Systems, 2003.
[5] D. Estrin, "Part IV: Sensor Network Protocols," Mobicom Tutorial Wireless Sensor Networks, 2002.
[6] J. Feng, F. Koushanfar, and M. Potkonjak, "System-Architectures for Sensor Networks Issues, Alternatives, and Directions", Proceedings of the 2002 IEEE International Conference on Computer Design (ICCD'02), 2002.
[7] J. J. Garcia-Luna-Aceves, and E. L. Madruga, "The Core-Assisted Mesh Protocol," IEEE JSAC, Aug. 1999.
[8] M. Gerla, S. Lee, and W. Su. "On-Demand Multicast Routing Protocol (ODMRP) for Ad Hoc Networks," Internet draft, 2000.
[9] W. Heinzelman, A. Chandrakasan, and H. Balakrishnan, "Energy-Efficient Communication Protocol for Wireless Microsensor Networks," Proc. 33rd Hawaii Int'l. Conf. Sys. Sci., Jan. 2000.
[10] C. Intanagonwiwat, R. Govindan, D. Estrin, J. Heidemann, and F. Silva, "Directed diffusion for wireless sensor networking," IEEE/ACM Transaction Network, Feb. 2003.
[11] L. Ji, and M. S. Corson, "A Lightweight Adaptive Multicast Algorithm," GLOBECOM, 1998.
[12] L. Ji, and M. S. Corson, "Differential destination multicast-A MANET multicast routing protocol for small groups," Proc. INFOCOM, 2001.
[13] C. Kappler, and G. Riegel, "A Real-World, Simple Wireless Sensor Network for Monitoring Electrical Energy Consumption", Proc. EWSN 2004, Berlin, Germany, Jan. 2004.
[14] Q. Li, J. Aslam, and D. Rus, "Hierarchical Power-Aware Routing in Sensor Networks," Proc. DIMACS Wksp. Pervasive Networking, May, 2001.
[15] S. Lindsey, and C. Raghavendra, "PEGASIS: Power-Efficient Gathering in Sensor Information Systems," IEEE Aerospace Conf. Proc., 2002.
[16] C. S. R. Murthy, and B. S. Manoj, "Ad Hoc Wireless Networks Architectures and Protocols", Prentice Hall Pub. , May 2004.
[17] D. Malan, T. F. Jones, M. Welsh, and S. Moulton, "Codeblue: An ad hoc sensor network infrastructure for emergency medical care", in Proceedings of the MobiSys 2004 Workshop on Applications of Mobile Embedded Systems (WAMES 2004), June 2004.
[18] A. Okura, T. Ihara, and A. Miura, "Branch Aggregation Multicast (BAM): An Energy Efficient and Highly Compatible Multicast Protocol for Wireless Sensor Networks," IEICE Transaction on Info and Systems, May 2006.
[19] K. S. Prabh, and T. F. Abdelzaher, "Energy-Conserving Data Cache Placement in Sensor Networks," ACM Transactions on Sensor Networks, Nov. 2005.
[20] E. M. Royer, and C. E. Perkins, "Multicast Operation of the Ad Hoc On-Demand Distance Vector Routing Protocol," ACM MOBICOM, Aug. 1999.
[21] K. Sohrabi, J. Gao, V. Ailawadhi, and G.J. Pottie, "Protocols for self-organization of a wireless sensor network", IEEE Personal Communications, Oct 2000.
[22] N. Sadagopan, B. Krishnamachari, and A. Helmy, "The ACQUIRE Mechanism for Efficient Querying in Sensor Networks," Proc. 1st Int'l. Wksp. Sensor Network Protocol and Applications, May 2003.
[23] V. Shnayder, M. Hempstead, B. Chen, G.W. Allen, and M. Welsh, "Simulating the power consumption of Large-Scale sensor network applications," Proc. ACM SenSys2004, Nov. 2004.
[24] S. Tilak, B. Abu-Ghazaleh, and W. Heinzelman, "A Taxonomy of wireless micro-sensor network models", Mobile Computing and Communications Review, 2002.
[25] C. W. Wu, Y.C. Tay, and C. K. Toh, "Ad Hoc Multicast Routing Protocol Utilizing Increasing id-numbers (AMRIS) Functional Specification," Internet draft, Nov. 1998.
[26] Y. Xu, J. Heidemann, and D. Estrin, "Geography-informed Energy Conservation for Ad-hoc Routing," Proc. 7th Annual ACM/IEEE International Conference Mobile Computer and Network, 2001.
[27] F. Ye, H. Luo, J. Cheng, S. Lu, and L. Zhang, "A Two-Tier Data Dissemination Model for large-scale Wireless Sensor Network," Proc. ACM/IEEE MOBICOM, 2002.
[28] W. Ye, J. Heidemann, and D. Estrin, "An energy-efficient MAC protocol for wireless sensor networks," Proc. 21st International Annual Joint Conference of the IEEE Computer and Communications Societies, 2002.
[29] Y. Yao and J. Gehrke, "The Cougar Approach to In network Query Processing in Sensor Networks," SIGMOD Record, Sept. 2002.
[30] http://140.116.72.80/~smallko/ns2/ns2.htm
[31] http://ipv6.willab.fi/kostas/src/Application-Traffic-Poisson/
[32] http://www.ieee802.org/15/
[33] http://www.isi.edu/nsnam/ns/