臺灣博碩士論文加值系統

IEEE 802.11 無線區域網路(Wireless Local Area Networks, WLAN)是目前國內通訊領域最重要的一項產業，也在一般家庭中使用。不過，由於使用者的資料是透過無線傳遞的，會有安全上的疑慮。另外，同一個BSS（Basic Station Set）下的 STAs（Station）在交換資料時，通信量（Throughput）都遠低於 802.11g 所定義的最高速率 54Mbps，這是受限於 802.11 網路連線機制之設計。本論文針對這兩個議題加以討論並實現改善方法。
本論文即針對 IEEE 802.11 Infrastructure 模式，研究開發如何讓使用者方便設定安全連線的機制，另引入 802.11e DLP（Direct Link Protocol）機制以提高系統效能。研究構想為設計 OBSS（One Button Security System）機制，意即使用者在 STA 端按下 Button，系統會在短時間內自動建立兩端的安全連線，解決第三者（Third-Party）有意或無意間竊聽的可能性。此外我們亦討論在同一個 BSS下的兩台 STAs 互傳資料時頻譜浪費的問題，本論文利用 DLP 建立兩台 STA 間的溝通協定，使原本應該透過 AP 轉發的訊息變為 STAs 間直接對傳，其通信量可提高至原本的兩倍，進一步提升系統效能。

IEEE802.11 has served as a vital link in wireless local area communication
networks（WLAN）and it has also extended its usage to home applications. Such
popularity has led to lots of concern on its security and througput performance. This
thesis is devoted on the research of possible solutions for these two issues. As a result,
for the IEEE 802.11 infrastructure mode, this thesis proposes an One-Button Security
System（OBSS） which can automatically activate the secure tunnel between two
STAs in a short time after a simple button push in contrast to the complex process
required to be executed by the user before. To improve the system throughput, the
work of this thesis also includes the implementation of DLP（Direct Link Protocol）
process on a WLAN system.

中文摘要 i
Abstract ii
Contents iii
List of Tables iv
List of Figures v
第一章 前言 1
第二章 802.11系統介紹 3
2.1 IEEE 802.11 MAC介紹 3
2.1-1 Distributed Coordination Function（DCF）3
2.1-2 Point Coordination Function（PCF）5
2.2 IEEE 802.11e MAC介紹 6
2.2-1 Enhanced DCF 7
2.2-2 HCF Controlled Channel Access 9
2.2-3 Direct Link Protocol 11
第三章 相關工作與文獻探討 15
3.1 Buffalo AirStation One-Button Security System（OBSS） 15
3.2 BroadCom Secure Easy Setup（SES） 18
3.3 無線網路安全 18
3.3-1 802.11 安全機制 18
3.3-2 802.11 認證機制 18
3.3-3 獲得更高的安全性 21
第四章 One-Button Security System與Direct Link Protocol 23
4.1 One-Button Security System 23
4.1-1 One-Button Security System工作原理 23
4.2 Direct Link Protocol 29
4.2-1 Direct Link Protocol的工作原理 29
第五章 系統實作與測試 32
5.1 系統架構 32
5.2 軟體簡介 33
5.2-1 AP端的模組介紹 33
5.2-2 Client端的模組介紹 34
5.3 One-Button Security System Testing 36
5.4 Direct Link Protocol Testing 39
第六章 結論與建議 42
Bibliography 44

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