针对现有可信计算平台中的直接匿名认证(DAA)方案存在计算过于复杂的问题,在已有的DAA协议基础上,结合M2M网络特点,提出了一种适用于M2M网络的I-DAA方案.该方案建立在椭圆曲线上的离散对数困难性问题的基础上,利用零知识证明和双线性映射理论,在证书申请阶段将部分DAA证书中原来由TPM计算的参数改为用系统公开参数替代,极大降低了资源相对较宝贵的TPM模块的计算量.同时,该方案中TPM的秘密信息改由TPM自己选取,从而减少不必要的计算开销.另外,TPM只需要申请一次DAA证书,以后即可直接向验证方提交验证信息,避免了一些现有协议的通信瓶颈.分析结果表明,I-DAA方案在保证安全的前提下降低了总体系统中尤其是TPM侧的计算复杂度,更适合于M2M系统及其他嵌入式系统应用环境.
Current anonymous attestation protocols(DAA) used in trusted computing platform always accompany with complicated computing.To solve this problem,the I-DAA protocol is proposed based on the mechanisms of existing DAA protocols and the characteristics of M2M network.Based on the theory of elliptic curve and the difficult problem of discrete logarithm,I-DAA also uses the zero knowledge proof and bilinear pairing theories.At the certification application stage,the public system parameters instead of those computed by TPM are used as certificated parameters to reduce the computational complexity of TPM whose computing ability is relatively more valuable.TPM selects the secret information by itself,which also reduces the computation cost of TPM.Moreover,it only needs to apply one time of DAA certification for TPM to use forever in the latter verification processing.This avoids the bottleneck of traditional DAA protocols.The analysis results show that the I-DAA scheme not only remains the security level of the traditional DAA protocols but also has great reduction of computational complexity,which makes it more suitable for M2M systems and other embedded application systems.