半诚实模型下公平高效的安全两方比较协议  

Fair and efficient protocol for secure two-party comparing under semi-honest model

作　　者：陈良[1,2] 高成敏[2] 

机构地区：[1]华南理工大学计算机科学与工程学院,广州510640 [2]广东警官学院计算机系,广州510232

出　　处：《计算机工程与应用》2010年第36期126-132,共7页Computer Engineering and Applications

摘　　要：姚氏百万富翁问题的实质是在秘密状态下比较两个数的大小,它是其他保密计算的一个基本模块,并在电子商务如投标、拍卖等应用中具有重要作用。当前的解决方案存在计算和通信开销较高、比较的数的范围有限等缺点。基于修改的ElGamal算法提出并证明了乘法和减法同态加密系统。基于此设计了半诚实模型下公平高效的安全两方比较协议。通过证明、实例和与其他协议比较表明其具有安全性、公平性、低的计算和通信开销和可秘密比较两个实数等特性。The essential of Yao’s millionaire problem is securely comparing two numbers,which is a basic building block of secure computations and has many important applications in e-commerce,such as bidding,auction and so on.But known solutions have some disadvantagesf,or example expensive costs of computing and communicatingl,imited ranges of compared numbers.This paper proposes a modified ElGamal algorithm,based on which multiplicative and subtractive homomorphic cryp-tosystem is presented and proved.Based on the homomorphic cryptosystem,Fair and Efficient Protocol for Secure Two-party Comparing（FEPSTC） under semi-honest model is constructed.The main properties of the FEPSTC are securityf,airnessl,ower costs of communication and computational complexity,and comparing real numbers.They are proved and illustrated by an ex-ample and by comparing with other protocols.

关 键 词：百万富翁问题 同态加密 减法同态 安全两方比较实数 保密计算 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]