【作者】 王颖学；

【导师】 廖晓峰；

【作者基本信息】 重庆大学 ， 计算机系统结构， 2007， 硕士

【摘要】 椭圆曲线密码体制是目前公钥体制中每比特密钥安全强度最高的一种密码体制。在相同安全强度条件下,椭圆曲线密码体制具有较短的密钥长度,较少的计算量、存储量和较小的带宽等诸多优点。目前,椭圆曲线密码体制已经被许多国际标准化机构作为标准化文件向全球颁布,被认为是下一代最通用的公钥密码系统,特别是在无线环境中有着广泛的应用前景。目前电子商务等领域中均使用以证书为基础的公钥密码系统来解决相关的安全问题。但是由于无线环境与有线环境之间存在着不可忽略的差异,如:较小的带宽、传输时有较大延迟、易断线、移动设备存储能力较低以及电力不足等,因此有线环境中的诸多安全体制是不适应于无线环境的。本文从身份认证体制入手,研究适合于无线环境的安全体制。本文首先介绍了与论题密切相关的椭圆曲线密码体制,然后就目前典型的身份认证算法和协议及其在无线环境中的应用进行了详细分析,最后结合椭圆曲线密码体制与自我验证的身份认证公钥密码系统,建立了一个基于GF ( 2m)域椭圆曲线的自我验证身份认证方案。本文主要工作如下:①本方案选用基于GF ( 2m)域上的椭圆曲线作为密码学基础,因此具有椭圆曲线密码系统密钥较短、运算效率较高的优点,这非常适合于无线环境;②本方案讨论了常见的主要快速标量乘法,对其中的两个算法做出进一步讨论和改进,加快运算速度以适应无线环境。③采用自我验证的身份认证体制,不使用证书就可以验证公钥的有效性,减少了验证证书的操作,节省了计算时间;④由于不使用证书,因此认证中心不必费时费力去维护证书目录,减少了认证中心的操作;⑤在身份认证的过程中同时进行了公钥有效性验证。通过对此方案安全性与复杂度的分析可知,此方案可有效减小密钥大小和运算复杂度、降低传输成本,因此非常适用于无线环境中。更多还原

【Abstract】 The highest safety strength of private key per bit in the Public-Key Cryptography is the Elliptic Curve Cryptography recently. Under similar secure conditions, the ECC has the advantages such as: less computation amounts, shorter length of private key, smaller storing and bandwidth. Moreover, it has been declared as standard documents adopted by many international standard institutions and regarded as the most universally used public key system, especially suitable in the wireless environment .At present, all of electronic commerce activities on the Internet employ the certificate-based public key cryptosystem to solve their related security issues. However, many security systems in lineate environment are not suitable for wireless environment, due to the noticeable difference between wireless environment and conventional lineate environment, for instance, the relatively narrow network bandwidth, the greater transmission delay time, the unstable network, the lower memory capacity and electronic power, etc.In this paper, we focus on the identity authentication system suitable for wireless environment.Firstly we introduce elliptic curve cryptosystem closely related to the thesis, then make a detailed analysis concerning algorithms and protocols about identity authentication and application in wireless environment, finally develop a self-certified identity authentication system based on elliptic curve over ( )GF 2 m,combining ellipticcurve cryptosystem and self-certified public key cryptosystem. The project includes the mian works as follows:①Owing to be based on elliptic curve over ( )GF 2 m, the project has the following advantages: the shorter key length and the higher efficiency, which are very suitable for wireless environment;②Discuss some major fast scalar algorithms. Make further study and improvement on two of them in to quicken the computational speed ;③Adopt self-certified public key cryptosystems, verify the validity of public key without certification and reduce the operation of validating certification and the amount of computation;④Owing to no need of certificates, the Certification Authority needs not to spend more time on managing the catalog of certificates, therefore reduce the operation of CA;⑤Both verification of the validity of public key and identity authentication can be achieved simultaneously.Based on the analysis of security and complexity of system, we believe that the project can effectively reduce the length of key, complexity of computation and the cost of transmission, which is very suitable for mobile equipments and wireless environments.更多还原