在普適計算環境(Pervasive computing environments，簡稱PCEs)的安全研究中，大部份是以討論與通訊安全相關的議題為主，如資料的隱密性、完整性或鑑別性。然而，隨著個人資料外洩所帶來的風險，使用者的隱私逐漸獲得重視，因此，如何在保有安全通訊的情況下，同時又能保障使用者的隱私，已成為普適計算研究的另一個重要議題。近年來，已有不少學者投入這方面的研究，也讓普適計算的安全機能又向前邁進。加入使用者隱私後，也衍生一個新的挑戰，就是在普適計算環境的服務提供者如何在匿名的前題下，對存取服務的使用者進行計費作業？本論文，我們考量個人隱私、通訊安全及計費機制等功能，提出了一個適於普適計算環境中存取服務的方法，此外，為了對服務資源的有效安全管理，我們兼顧使用者的存取控制管理。我們的技術也考慮使用者漫遊跨網存取服務的情境，最後，我們利用BAN-Logic來證明使用者與服務提供者在通訊過程時，能達成鑑別效果及其所建立的會議金鑰(session key)之正確性。

Communication security is widely discussed in pervasive computing environments (PCEs), such as data confidentiality, integrity and authentication. However, due to the risk of leakage of individual data, people increasingly paid attention to user's privacy. It preserving user’s privacy also is an important issue of PCEs. There are many researchers devote themselves to improve the security of PCEs. But it comes with a new challenge when user's privacy is taken into account. That is how do service providers of PCEs provide services and charge to anonymous user. This thesis takes personal privacy, communication security and accounting mechanism into consideration to propose a protocol good for accessing services in PCEs. We consider the user access control to utilize the service resource efficiently. Also, our protocol provides services to roaming users. In addition, we verify correctness of the session key used in communication between the user and service provider based on BAN Logic.

目錄
目錄	I
圖目錄	III
表目錄	IV
第一章 緒言	1
1.2普適計算環境的介紹	3
1.3安全需求討論	5
1.4我們方法的概述及結構	6
第二章 相關研究工作	10
2.1 Ren等人之方法的環境說明	10
2.2 Ren等人的方法說明	12
2.2.1 符號定義	12
2.2.2 使用者授權階段	13
2.2.3 使用者存取階段	14
2.3 分析與討論	17
第三章 普適計算之漫遊、隱私和存取之研究	20
3.1 環境及符號說明	20
3.2 網內存取資料	22
3.2.1 產生憑據及授權階段	22
3.2.2 初次存取階段	24
3.2.3 後續存取階段	27
3.3漫遊存取資源	30
3.3.1 漫遊存取階段	31
3.3.2 憑據更新階段	35
第四章 安全分析與討論	38
4.1 安全特性的討論	38
4.2 會議金鑰鑑別功能的證明	44
4.2.1 符號定義	45
4.2.2 邏輯規則說明	45
4.2.3 正規驗證	48
第五章 效能分析與比較	55
5.1 效能分析	55
5.2 功能討論及比較	59
第六章 結論與未來研究工作	62
參考文獻	63
附錄—英文論文	67

圖目錄
圖1. 簡易的普適計算環境	4
圖2.  Ren等人的使用者授權階段	13
圖3.  Ren等人的使用者存取階段	15
圖4.  Ren等人的使用者後續存取服務	17
圖5. 憑據產生及授權階段	22
圖6. 初次存取階段	25
圖7. 後續存取階段	28
圖8. 使用者漫遊的普適計算環境	30
圖9. 漫遊存取階段	31
圖10. 憑據更新階段	36
圖11. 系統整體通訊量比較	57

表目錄
表1. 符號說明表	12
表2. 安全功能比較表	44
表3. 安全強度比較表	56
表4. 初次使用階段通訊量比較表	57
表5. 後續使用階段通訊量比較表	57
表6. 計算量比較表	58
表7. Hwang等人的計算效能比較表	59

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