Research Of Virtual Machine Trusted Auditing Method Based On Improved Expectation Value Decision Method

With the rapid development of cloud computing,the structural features of the cloud computing environment have caused more and more security problems.The essential feature of the cloud computing model is the separation of data ownership and management rights.Users migrate the data to the cloud and lose direct control over the data.Users need to manage the data with the help of the cloud computing platform.The reliability of the virtual machine running environment is the key factor for the further promotion and effective use of cloud computing.In this dissertation,trusted computing,virtual machine introspection,risk decision,encryption and auditing are combined organically.A trusted audit method of virtual machine based on improved expectation value decision method is proposed.Among them,the trusted root and trusted chain of trusted computing technology are used to guarantee the credibility of virtual machine startup.The information needed by audit is obtained by using the technology of virtual machine introspection,and the audit plan is selected by risk decision method.The security of the audit scheme is guaranteed by the encryption mechanism,and the credibility of the virtual machine is determined by the audit scheme.This scheme provides several security protection levels for the user's virtual machine,and the user selects the corresponding security level for the virtual machine according to its own security requirements.According to the level of security protection selected by users,we use the improved expected value decision method to calculate the expected value of each audit plan,and the most profitable audit plan is the best audit plan that meets user needs.Finally,the simulation experiment results show that the scheme has good performance and effectiveness.The innovation of this dissertation are as follows:(1)the design of system architecture for audit and audit scheme selection for virtual machine credibility.(2)The expectation value decision method is improved,the use scene of the expected value decision method is redefined,and the calculation method of the cost and income value of the audit scheme is put forward.(3)an encryption mechanism is proposed to protect the security of the selected audit scheme.