Verifiable Outsourcing Computing Based On Two-Server Model

With the advent of the big data age and the rapid development of cloud computing technology,outsourcing computation has become a way for more and more organizations and individuals to choose computing tasks.Outsourcing computation means that users with limited computing resources outsource complex computing tasks to cloud servers in order to save local resources.However,while bringing convenience,the outsourcing computation services has produced some security problems that need to be solved urgently.The computing process of the cloud server is not public,and there may be behavior of deceiving the user.The computing results returned by the cloud server may not be the data that the user needs.Verifiable outsourcing computation is an important way to solve the above problems.How to use the minimum cost for rapid and correct verification has become the focus and difficulty of the current research.However,there are two main problems in the current verifiable outsourced computation scheme:(1)In single server scenario,the user needs to verify the computing results returned by the cloud server with the heavy cryptographic protocol,which undoubtedly increases the workload of the user.The original intention of outsourced computation is to reduce the cost of local resources,which is contrary to the original intention of users.(2)In multi-server scenarios,redundant computing is often used,where the same computing task is outsourced to multiple cloud servers to check whether they return the same result.However,multiple cloud servers may collude to return incorrect results to the user.In view of the above problems,the thesis works as follows:(1)A system of linear equations(SLE)based on matrix blinding technique is proposed to verify the outsourcing calculation scheme.The scheme is based on the matrix blinding technology,adopts the data distribution idea,and through the segmentation calculation between the two cloud servers,the user cross-calculates the results to achieve quick verification of the results,reducing the cumbersome steps of the user verification calculation results and improving the efficiency.(2)A general intelligent contract-based anti-collusion verifiable outsourcing computing solution is proposed,which achieves the purpose of fast verification through redundant calculation between two cloud servers,and reduces the workload of user verification calculation results.Moreover,the scheme uses cryptography technology and blockchain intelligent contract to trigger the game between the participants.Under reasonable assumptions,it proves that the participants will not collude,but will honestly calculate and return a correct calculation result to the user to achieve the sequential equilibrium of the game.