| 摘要: | 現今主流即時通訊系統不論主從式架構與點對點架構都要求使用者必須事
先向管理中心註冊,因此管理中心能夠知道所有使用者的身份,其身份隱私保護 就完全建構在管理中心的信賴上,但是管理中心被惡意使用者攻擊,則使用者的 身份隱私就不保。為了保護使用者身分之隱私,本研究提出一個利用多重碰撞後 門雜湊函數保護使用者身分隱私之去中心化即時通訊協定。本協定中,每位使用 者皆各自隸屬一個群組,每個群組包含一個管理者發行使用者之憑證,用來隱藏 使用者之身分。本協定可協助任何兩個已建立信任之群組的使用者在不洩漏各自 真實身分的前提下建立通訊,並且利用多重碰撞後門雜湊函數於正在進行中的通 訊只需少量的計算成本就能保護通訊雙方的匿名性。
All the existed instant messaging systems require the users’ registration to the
management center, regardless of the client-server or peer-to-peer architectures. Therefore, the management center knows each user’s identity, and the users’ identity privacy completely relies on the trust of the management center. To protect the users’ identity privacy, a decentralized instant messaging protocol is proposed with the help of multiple-collision trapdoor hash functions. In our protocol, each user belongs a small group with a group manager and the group manager issues the certificate for its members. The certificate is used to hide the users’ identity from the people except the manager of the small group. For any two users belonging two groups that trusted one another, our protocol can help the two users to construct a communication connection without leasing their real identities. After the hard work to initialize the communication connection, the on-going connection just needs a lighter cost to keep anonymous communications, with the help of multiple-collision trapdoor hash functions. |
