基于单服务器的群上幂指数安全外包计算方案

Secure and Verifiable Protocol for Outsourcing Group Power Exponent to a Single Server

随着云计算的快速发展和大数据时代的到来,如何将一些耗时的计算任务安全地外包给不完全可信的公共云服务器引起了广泛关注.基于单服务器模型,提出了一个新的具有隐私保护的群域上的幂指数运算安全外包方案GEXP(outsourcing power exponent on a group field),能够有效避免双服务器模型存在的共谋攻击问题.与已有方案相比,方案GEXP能够以100%的概率检测出云服务器返回的错误计算结果,确保了用户对外包计算结果的可完全验证.此外,给出了方案GEXP在现有广泛研究的云存储数据完整性验证的具体应用.

With the rapid development of cloud computing and the arrival of large data age,users are confronted with huge data and information to be processed which means massive amounts of difficult tasks.Consequently,how to securely outsource some time-consuming computing tasks to an untrusted public cloud server has aroused widespread concern.To realize the data privacy protection and the verifiability of calculation results in outsourcing computing,based on the single server model,this paper proposes a new privacy-preserving protocol for outsourcing power exponent on a group field,called GEXP(outsourcing power exponent on a group field).The scheme can prevent adversaries from getting any input output data.Moreover,it effectively avoids the collusion attack in the dual server model.Compared with the existing schemes,GEXP can detect the wrong result returned by the cloud server with 100%probability,which ensures that the user can fully verify the result of outsourcing calculation.The formal security analysis and experiments indicate that our scheme is to protect privacy and highly efficient.In experiments,we compare our scheme with other state-of-the-art schemes to further demonstrate the superiorities in security and efficiency.In addition,in order to prove the practicality of our scheme,this paper gives the specific application of GEXP in cloud storage data integrity verification.