在傳統移動式IP的協定中，三角繞送問題不但會增加封包傳送時的延遲性，更可能造成封包的大量遺失。在本篇論文中，我們提出一個適性化的路徑最佳化架構，此架構是根據使用者的移動速度來判定是否要進行路徑最佳化。我們的方法包括移動式繞送表的採用以及成本函式的建構。成本函式的計算是根據連線成本以及傳送註冊訊息成本加總所得，這些成本包含了建立連線時網路資源的使用、傳送訊息所消耗的網路資源以及各個代理人上處理訊息的負載。模擬的結果顯示我們的方法在降低總成本上有較好的表現。

In mobile IP, a triangular routing problem usually leads to additional delays and non-seamless handoff, which causes the loss of a large amount of in-fly packets. In this thesis we propose an adaptive route optimization scheme that considers the seamless handoff and mobility rate. The proposed scheme adopts the mobile routing table scheme and includes an efficient cost function. The cost function is a trade-off between network bandwidth utilized by the routing path, signaling messages and processing loads of agents. The primary idea is to adaptively determine when to perform route optimization. The effect of the mobility rate and the cell sojourn time of a mobile node are studied. Both new call and handoff call are considered in the cost calculation. Simulation result shows that the proposed scheme can effectively reduce the total cost composed of link and signaling costs.

1 INTRODUCTION 1
1.1 Overview of Mobile IPv4 1
1.2 Related Work 3
2 THE PROPOSED ADAPTIVE ROUTE OPTIMIZATION SCHEME 8
2.1 System Model 8
2.2 The Proposed Signaling Messages Transmittal Procedures 9
2.3 The Mathematical Model 13
2.3.1 Cell Sojourn Times 13
2.3.2 Cost Function of adaptive route optimization with mobility rate (AROMR) 16
3 PERFORMANCE EVALUATION 23
3.1 The Total Cost 24
3.2 The Signaling Cost 30
3.3 The Number of Route Optimizations 32
4 CONCLUSION 36
REFERENCES 37

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