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A Testing Method of the Residual Information Clearance in Virtual Machine for the Cloud Operating System

The most important advantage of the cloud computing is resource sharing, including CPU, memory, disk and network, and so on. Resource sharing means the efficiency improvement of the resource usage. However, resource sharing also means new security threats, especially the threat of the data leakage of the memory and disk, so it is very important to take measures to protect the residual information. The residual information protection has been the focus of information security since 1985, and the methods of eliminating residual information have also attracted much attention. The testing of residual information clearance has formed a more effective method at the OS level, but at present, there is no effective method to detect the residual information (including disk and memory) in the virtual machine for the cloud operating system, and it cannot make a correct evaluation of the security of the cloud computing platform. In this paper, a testing method of the residual information clearance in the virtual machine is proposed, which can be used to detect the residual information of the memory and disk, it also can detect whether the residual information is removed after the resource is released immediately or just before the resource is reassigned. This paper can also provide technical guidance for the security evaluation of the cloud computing platform.