為了對簽章者提供更高的匿名性，我們提出了具強指定驗證者的匿名環簽章。在具強指定驗證者的匿名環簽章中，對指定驗證者而言簽章者必定是環成員的其中一人，而對其他人而言簽章者卻有可能是任何人。所以在指定驗證者眼中，此簽章對簽章者的隱私提供了簽章者模糊性，而在其他任何人眼中，此簽章則是對簽章者的隱私提供了簽章者匿名性。為了能達到簽章者的匿名性，我們希望讓所有人都能偽造此簽章。而為了能達到簽章者的模糊性及確保簽章的可信度，我們希望讓指定驗證者仍然可以驗證簽章的合法性，確認是由環成員中的某一人所簽署。在我們方法中為了確保簽章者的利益，提供了可以讓簽章者證明該簽章是他所簽署的演算法。最後我們在安全分析上也證明了我們的方法是滿足環簽章的正確性及不可偽造性。 To provide more anonymous protection for the actual signer, the first ring signatures with strong specified verifiers is proposed in 2007. In the ring signature scheme with strong specified verifiers, any member in the ad-hoc ring is able to generate ring signatures, so ring signatures provide signer ambiguity to protect the actual signer’s anonymity. Moreover, only the specified verifier is convinced that the actual signer is one of the ring members. The other only guesses the actual signer may be one of the ring members and the specified verifier. If the other one guesses the actual signer being not only the ring members but also any possible ones, the scheme with strong specified verifiers provides the maximum anonymity protection for the actual signer. In order to convince the specified verifier, the specified verifier is still sure that the actual signer is one of the ring members. Therefore, the first anonymous ring signature scheme with strong specified verifiers is proposed. In our scheme, the signer admission is also provided for the actual singer to prove who the actual signer is. The provable security analysis is provided to show that our scheme satisfies the ring signatures’ correctness and unforgeability.
