802.11無線區域網路的盛行，使得人們可以自由地使用具有802.11無線網路卡的電腦在有部署無線存取點(access point)的環境下，隨意使用網際網路。然而，802.11無線區域網路的便利性卻造成潛在的無線網路安全，如：DOS和DDOS、man in the middle attack、機密性資料的竊取等安全問題。802.11 rogue devices為組織機構內未經授權的802.11 mobile devices，在一個使用802.11無線區域網路的組織機構內，造成802.11無線區域網路的安全問題大多因於802.11 rogue devices。本論文的目的在於能夠在一個組織機構內偵測802.11 rogue devices和找出802.11 rogue devices的可能實際位置(又稱802.11 rogue devices的定位)。
在偵測802.11 rogue devices上，前人的研究大多使用”白名單”技術；在802.11 rogue devices的定位上，前人所研究的802.11定位技術大多為static scene analysis和radio propagation model以對802.11 mobile devices定位。
現今的802.11定位技術大多已實作為一個獨立的系統，稱為802.11定位系統(802.11 Location System)。然而，以現有的802.11定位系統尚無法定位802.11 rogue devices，因為目前的802.11定位系統大多需要802.11 mobile devices主動提供802.11無線訊號強度，而802.11 rogue devices為組織機構內未經授權的802.11 mobile devices，自然不希望被組織機構內的定位系統找出其位置，因此不會主動提供802.11無線訊號強度讓組織機構的802.11定位系統找出其位置。除此之外，現存的802.11定位系統只能找出具有某個廠商的802.11無線網路模組(或晶片組)的802.11 mobile devices，但是802.11 rogue devices不大可能只是使用某個廠商的802.11無線網路模組，故無法準確找出802.11 rogue devices的可能實際位置。
本論文實作一個802.11定位系統以偵測802.11 rogue devices和找出802.11 rogue devices的可能實際位置。偵測802.11 rogue devices為”白名單技術”，找出802.11 rogue devices的802.11定位技術為利用802.11無線訊號強度差的Static Scene Analysis，在Static Scene Analysis上，會使用四種不同的定位演算法(location estimation algorithm)以推估802.11 rogue devices的實際位置。

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