CAJ | 학술논문

针对现有的可传递电子现金系统在传递协议中电子现金长度和传递次数成正比的问题，利用 Groth-Sa-hai 证明系统和累加器原理，首次提出花费链构建法，并在标准模型下构建一个具有最优匿名性的传递协议中电子现金长度不变的可传递电子现金系统．基于花费链构建法，用户无需存储任何花费凭证；与现有系统相比，在传递协议中，用户传递电子现金的长度是常量；在安全性上，新系统具有最优匿名性，即全匿名性、完美匿名性1和完美匿名性2．最后，在标准模型下给出系统的安全证明，该系统具有不可伪造性、最优匿名性、不可重复花费性和不可诬陷性．
침대현유적가전체전자현금계통재전체협의중전자현금장도화전체차수성정비적문제，이용 Groth-Sa-hai 증명계통화루가기원리，수차제출화비련구건법，병재표준모형하구건일개구유최우닉명성적전체협의중전자현금장도불변적가전체전자현금계통．기우화비련구건법，용호무수존저임하화비빙증；여현유계통상비，재전체협의중，용호전체전자현금적장도시상량；재안전성상，신계통구유최우닉명성，즉전닉명성、완미닉명성1화완미닉명성2．최후，재표준모형하급출계통적안전증명，해계통구유불가위조성、최우닉명성、불가중복화비성화불가무함성．
There exist some problems such that the length of the E-cash is proportional to the number of the transfer protocol in the transferable E-cash system.Using the Groth-Sahai (GS)proof system and accumulator,we first propose spending chain algo-rithm and design a transferable E-cash system of equal length with optimal anonymity in the standard model.Based on the spending chain,the users do not need to keep in memory the data associated to all past transactions.Compared with the existing systems,the length of the E-cash is constant in the spending protocol.Meanwhile,the new system achieves the optimal anonymity,such as full anonymity,perfect anonymity 1 and perfect anonymity 2.At last,the security proof of the systemis given in the standard model,i.e. unforgeability,anonymity,identification of double spender and exculpability.