本論文提出一個適用於全球行動網路(Global Mobility Network，GLOMONET)漫遊服務的匿名鑑別機制，當行動使用者向外部代理人(foreign agent，FA)申請漫遊服務請求時，外部代理人無法得知行動使用者的身分資訊，以保障行動使用者資訊的安全，而且本地代理人(home agent，HA)無須維護任何行動使用者的認證表來鑑別行動使用者。本論文後段提出正規化論證來說明我們的機制如何有效地滿足使用者匿名、相互認證、會議金鑰安全以及完美向前保密性等安全需求。除此之外，一些常見的攻擊手法，像是重送攻擊、中間人攻擊、冒名頂替攻擊及內部攻擊等，我們的機制也都能夠有效地防禦。

This thesis presents an anonymous authentication scheme for roaming service in global mobility networks, in which the foreign agent cannot obtain the identity information of the mobile user who is sending the roaming request. In addition, the home agent does not have to maintain any verification table for authenticating the mobile user.
We give formal analyses to show that our proposed scheme satisfies the security requirements of user anonymity, mutual authentication, session-key security, and perfect forward secrecy. Besides, some possible attacks on the proposed scheme are discussed, such as the replay attack, the man-in-middle attack, the impersonation attack, and the insider attack.

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