臺灣博碩士論文加值系統

TCP (Transmission Control Protocol) 協定是許多重要的網路應用，如：網頁瀏覽、檔案下載等軟體所使用的傳輸工具。但是傳統TCP會因為反應過度，因其假設所有封包遺失皆是因為網路壅塞(Congestion Loss)而遭路由器丟棄所致。使用TCP Westwood++ 可以改善此問題，因為TCPW++ 使用了AIAD (Additive Increase Adaptive Decrease) 的機制來做壅塞視窗(Congestion Window) 的控制。
所以在本論文中，我們使用TCP Westwood++ 針對瓶頸頻寬(bottleneck band-width)、點對點傳播時間（round trip propagation time）、緩衝區空間（buffer space）、連線錯誤率（link error rate）和不同的傳輸機制，如：TCP Reno、TCP Westwood做比較。模擬結果得知TCP Westwood++ 的效能會優於其他的傳輸協定。

The Transmission Control Protocol (TCP) is the transport protocol for many impor-tant applications such as web browsing and file transfer. The traditional assumption for TCP that all packet losses are due to congestion at intermediate routers may not be valid in wireless environment. TCPW++ shows significant improvements in throughput per-formance over TCP Reno because TCPW++ uses the additive increase adaptive decrease (AIAD) to control the congestion window.
This thesis evaluates TCP Westwood++ further by comparing it with other TCP variants such as TCP Reno, TCP Westwood and TCP Westwood+. Our simulation shows that TCP Westwood++ is better than other TCP variants by achieving higher throughput for different conditions such as bottleneck bandwidth, round trip propagation time, buffer space, and link error rate.

ABSTRACT (in Chinese)

ABSTRACT (in English)

ACKNOWLEDGMENT

LIST OF FIGURE

LIST OF TABLE

CHAPTER 1 INTRODUCTION
1.1 Overview
1.2 Development of the TCP
1.3 Organization of thesis

CHAPTER 2 AN OVERVIEW OF TCPW
2.1 Overview
2.2 TCPW++
2.3 Bandwidth Estimation

CHAPTER 3 SIMULATION MODEL AND RESULES
3.1 Simulation Topology
3.2 Simulation Parameters
3.3 Comparison with Other Protocols
3.4 Lossy Connection
3.5 Ideal Connection
3.5.1 Bottleneck Bandwidth
3.5.2 Round Trip Propagation Time
3.5.3 Buffer Size
3.6 Other simulation results
3.7 Low-Pass Filter’s Effect
3.8 Congestion Windows

CHAPTER 4 CONCLUSIONS

REFERENCES

APPENDIX A

APPENDIX B

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