This report was funded by an Information Research Institution and carried out by Cheng-kang Chu with other researchers from Chinese Academy of Sciences. It was published by the IEEE CS in 2013.
The authors provide an analysis and evaluation of the security about the current three main cloud storage services, which are Google Drive, Dropbox and Microsoft SkyDrive respectively. They put their opinion that each of the cloud storage services has same security weakness (Cheng-kang, 2013).
This report can be split into three parts. On the beginning the authors introduce the general way for sharing data in these three cloud storage services, which are public sharing, private sharing and secret URL sharing. They think that public sharing is the easiest way for sharing data, but people cannot access and apply the private information by using this method. The most secure way is private sharing, but it is very trouble. People have to register an account and sign into the system. At the same time, the system could not be registered by the same computer with same IP address. However, there is a balance between the public sharing and the private sharing, which is Secret-URL sharing. It can let people access the shared information without an account access, if they have required a data link address (Cheng-kang, 2013).
The authors then look to see the problem on the three ways from each cloud storage services. For secret-UPL sharing, when want to share a data with another people, the URL can be used to access the data by the people. Even if the data has been removed and other data associated with the same data name, it still can be accessed by the same name. For public sharing, when delete a file from cloud storage services, the file is moved to a "Recycle Bin", people can still access the file even if it has been moved, because there is a cache data on the DNS. For private sharing, it is the same problem with public sharing. The data can still be accessed by