因應日益增加的行車安全與交通流量管控的需求，近年來車載網路(VANET)已成為相當重要且熱門的研究議題，隨著車載網路相關技術的發展與進步，車載網路中的通訊安全需求逐漸被重視，如何在快速且眾多的車輛間安全地傳遞資訊則成為一大挑戰，而其中值得探討的議題則是車載網路中的安全認證問題。在進行通訊之前，必須先確認通訊的對方是可以被信任的，因此裝置彼此之間需要有合適的認證機制，但在車載網路的環境底下，由於行車速度較快，故傳統的認證機制有可能因為較花費時間而無法適用。同時，在使用車載網路時，為了考量使用者的隱私性，避免使用者的位置暴露，故需要採用匿名的方式通訊。因此，本文基於批次驗證的匿名簽名(AKABA)來提出改進方案，增加車載認證的安全度。

According to the increasing traffic safety and control needs, developing applications in vehicular adhoc network (VANET) has become an important and popular research topic in recent years. How to securely and rapidly transmit the messages between the vehicles is a major challenge in developing applications of VANET. To resist various malicious abuses and security attacks, the users in VANET needs to have an appropriate authentication mechanism to help them confirm that whether the communication objects can be trusted before communicate with them. However, the transmission time allowed to communicate with other objects can be very short in VANET due to cars are moving fast. Hence, the conventional authentication mechanisms cannot be applied to vehicular communication network as they spend too much time. In addition, in order to protect the user's privacy and avoid to disclosing the user's location, anonymous communication techniques are needed in VANET. Therefore, we propose an Anonymous Batch Authentication Scheme (ABAS) based on an Anonymous Batch Authenticated and Key Agreement Scheme (AKABA) to increase safety in data transmission over vehicular communication network.

目錄
目錄	III
表目錄	V
圖目錄	VI
第一章　緒論	1
1.1　研究背景	1
1.1.2　車載網路實際的應用	1
1.2　研究動機與目的	2
1.3　論文架構	4
第二章　文獻探討	5
2.1　相關密碼學探討	5
2.1.1　橢圓曲線密碼學	5
2.1.2　橢圓曲線金鑰交換演算法	7
2.1.3　橢圓曲線數位簽章演算法	8
2.2　相關機制探討	10
2.2.1　Manvi學者認證機制	10
2.2.2　Aslam學者認證機制	11
2.2.3　Lo-Yao Yeh學者認證機制	12
第三章　提出的修改提案	14
3.1  環境元件	14
3.2　環境假設	15
3.3　系統建置	16
3.3.1　系統初始	17
3.3.2　匿名產生	18
3.3.3　RSU裝置身分驗證	19
3.3.4　批次驗證	24
第四章　安全性分析	27
4.1　安全需求分析	27
4.2　抵擋惡意攻擊	28
第五章　結論	30
5.1　結論	30
5.2　研究貢獻	30
5.3　未來展望	30
參考文獻	31


表目錄
表 一、車載網路分析(本研究整理)	3
表 二、RSA和ECC金鑰長度比較(NIST)	9
表 三、符號表	16
表 四、各協定安全性比較(本研究整理)	29


圖目錄
圖 一、橢圓曲線圖形	5
圖 二、橢圓曲線加法	6
圖 三、橢圓曲線乘法	7
圖 四、ECDH金鑰交換	8
圖 五、ECDSA簽章產生和驗證	9
圖 六、MANVI機制網路環境	11
圖 七、ASLAM機制網路環境	12
圖 八、車載網路的運作	15
圖 九、匿名產生流程	18
圖 十、偽造問題	20
圖 十一、攔截問題	20
圖 十二、RSU裝置身分驗證	21
圖 十三、使用者移動到下一個RSU裝置	23
圖 十四、批次驗證流程	24

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