由於整合網際網路和移動性隨意網路的方法經常利用gateway來達成，所以對隨意式網路中的移動節點而言，利用gateway探索方法來取得通往gateway 的路徑資訊是非常重要的課題，其中混合式gateway探索方法結合了主動式和被動式探索方法的優點。本篇論文旨在建立一個可調式gateway探索演算法，利用估算網路環境control overhead的資訊來調整gateway advertisement message的TTL（Time-to-live），進而限制control overhead的產生。透過模擬顯示出在不同欲存取網際網路的節點數量環境下，我們所提出的可調式gateway探索演算法可將gateway advertisement message的TTL調整至適當值，讓網路的control overhead較低。

Since gateways are usually used to integrate the Internet and MANET (Mobile Ad Hoc Network), the gateway discovery approaches is important for mobile nodes in MANET to obtain the route to gateways. The hybrid gateway discovery approach can be configured through adjustment of the single parameter, the TTL (Time-to-live) of the advertisement. This thesis aims to develop an adaptive gateway discovery algorithm to adjust the TTL of advertisement by estimating the control overhead and then effectively adjusts the generation of control overhead in the integrated network. Through the simulation, we demonstrate that this adaptive gateway discovery algorithm can adjust the appropriate TTL of advertisement in different number of mobile nodes which desire to access Internet.

中文摘要.....................................................................................................I
英文摘要...................................................................................................II
目錄..........................................................................................................III
圖目錄.......................................................................................................V
表格目錄.................................................................................................VII
字母縮寫對照表...................................................................................VIII
第一章 緒論..............................................................................................1
1.1 前言.......................................................................................1
1.2 研究動機...............................................................................3
1.3 論文架構...............................................................................4
第二章 相關研究和背景知識..................................................................5
2.1 相關研究...............................................................................5
2.2 背景知識...............................................................................7
2.2.1 移動性隨意式網路及其路由協定............................7
(1) 表格驅動路由協定.............................................8
(2) 要求驅動路由協定...........................................10
(3) 混合路由協定...................................................10
2.2.2 Mobile IP...................................................................11
2.2.3 Gateway探索方法的分類........................................14
(1) 主動式Gateway探索演算法............................14
(2) 被動式Gateway探索演算法............................16
(3) 混合式Gateway探索演算法............................17
第三章 可調式Gateway探索演算法....................................................19
3.1 網路架構.............................................................................19
3.1.1 MANET端的路由協定............................................20
3.1.2 Gateway探索方法....................................................24
3.1.2 Mobile IP註冊程序...................................................26
3.2 估算Overhead以及可調式Gateway探索演算法.............26
3.2.1 Proactive Overhead的分析.......................................28
3.2.2 Reactive Overhead的分析........................................29
3.2.3 可調式Gateway探索演算法...................................31
第四章 模擬結果及分析........................................................................37
4.1 網路模擬器NS....................................................................37
4.2 模擬研究.............................................................................38
4.2.1 Total Overhead的分析……....................................39
4.2.2 Oup_threshold和Odown_threshold值......................................40
4.2.2 估算Overhead方程式.............................................43
4.2.3 效能比較..................................................................45
第五章 結論............................................................................................47
參考文獻..................................................................................................48

[1] P. Bhagwat. and C. Perkins, “Highly Dynamic Destination-Sequenced Distance Vector Routing（DSDV）for Mobile Computers,” in proc. of the ACM SIGCOMM Symposium on Communications, Architectures and Protocols, pp.234–244 , London, UK, Sept. 1994.
[2] J. Broch, D. Maltz, and D. Johnson. Supporting, “ Hierarchy and Heterogeneous Interfaces in Multi-Hop Wireless Ad Hoc Networks,” in proc. of the I-SPAN’99, pp. 370–375, Perth, Australia, June 1999.
[3] C.-C. Chiang, H.-K. Wu, W. Liu, and M. Gerla, “Routing in Clustered Multihop, Mobile Wireless Networks with Fading Channel”, in proc. of the IEEE Singapore International Conference on Networks, pp. 197–211, Apr. 1997.
[4] R. Dube, et al, “Signal Stability based Adaptive Routing（SSA） for Ad Hoc Mobile Networks,” IEEE Personal Communication Magazine, pp. 36–45, Feb. 1997.
[5] M. Ergen , A. Puri, “ NEWLANA – Mobile IP Enrished Wireless Local Area Network Architecture,” in proc. of the Vehicular Technology Conference 2002, pp. 2449–2453, Vancouver, Canada, Sept. 2002.
[6] Z. Haas and M. Pearlman, “The Zone Routing Protocol（ZRP）for Ad Hoc Networks,” IETF MANET Draft, June 1999.
[7] C. Hedrick, “Routing Information Protocol（RIP）,” IETF RFC 1058, June 1988.
[8] M.-H. Jiang and R.-H. Jan, “An Efficient Multiple Paths Routing algorithm for Ad-hoc Networks,” in proc. of the 15th International Conference on Information Networking, pp. 544–549, Beppu, Japan, 2001.
[9] D. B. Johnson, J. Broch, and D. A. Maltz, “Supporting Hierarchy and Heterogeneous Interfaces in Multi-Hop Wireless Ad Hoc Networks.” in proc. of the Workshop on Mobile Computing, pp. 370–375, Perth, Australia, June 1999.
[10] U. J¨onsson, F. Alriksson, T. Larsson, P. Johansson, and G. Q. M. Jr, “MIPMANET - Mobile IP for Mobile Ad Hoc Networks,” in proc. of the 1st Workshop on MobiHOC’ 00, pp. 75–85, Boston, Massachusetts, Aug. 2000.
[11] H. Lei and C. E. Perkins, “Ad Hoc Networking with Mobile IP,” in proc. of the 2nd European Personal Mobile Communications Conference, pp. 197–202, Bonn, Germany, Oct. 1997.
[12] S. Murthy and J. J. Garcia-Luna-Aceves, “A Routing Protocol for Packet Radio Networks,” in proc. of ACM MOBICOM’95, pp.86–95, Berkeley, California, Nov. 1995.
[13] V. Park and M. S. Corson, “A Highly Adaptive Distributed Routing Algorithm for Mobile Wireless Networks,” in proc. of the IEEE INFOCOM’97, pp. 1405–1313, Kobe, Japan, Apr. 1997.
[14] C. E. Perkins, “Mobile IP Design Principle and Practices”, Addison Wesley, 1997.
[15] C. Perkins and E. M. Royer, “Ad-hoc On-demand Distance Vector Routing,” in proc. of the 2nd IEEE Workshop on Mobile Computing Systems and Applications, pp. 90–100, New Orleans, USA , Feb. 1999.
[16] C. E. Perkins, E. M. Belding-Royer, and S. R. Das, “Ad Hoc On-demand Distance Vector (AODV) Routing,” IETF Internet Draft, June 2002.
[17] C. E. Perkins, “IP Mobility Support for IPv4,” RFC 3344, Aug. 2002.
[18] J. Raju and J. J. Garcia-Luna-Aceves, “A Comparison of On-demand and Table-driven Routing for Ad Hoc Wireless Networks,” in proc. of IEEE the ICC, pp. 1702–1706, New Orleans, USA, June 2000.
[19] P. Ratanchandani and R. Kravets, “A Hybrid Approach to Internet Connectivity for Mobile Ad Hoc Networks,” in proc. of the IEEE Wireless Communications and Networking Conference (WCNC), pp. 1523–1527, New Orleans, USA, Mar. 2003.
[20] S. Singh, M. Woo, and C. S. Raghavendra, “Power-Aware Routing in Mobile Ad Hoc Networks,” in proc. of the ACM/IEEE MobiCom’98 Conference, pp. 181–190, Dallas, USA, Oct. 1998.
[21] Y. Sun, E. M. Belding-Royer, and C. E. Perkins, “Internet Connectivity for Ad hoc Mobile Networks,” International Journal of Wireless Information Networks special issue on Mobile Ad hoc Networks: Standards, Research, Application, pp. 75–88, Apr. 2002.
[22] Y. Tseng, C. Shen and W. Chen, “Integrating Mobile IP with Ad Hoc Networks,” IEEE Computer, Vol. 36, No. 5, pp. 48–55, May 2003.