LAUSR

Abstract The purpose of this paper is to improve the efficiency and security of the cloud storage user data, a method of multi-bit data de-duplication-based cloud storage channel covert is proposed. Firstly, a covert channel design framework for cross-users including cloud storage providers, victims and attackers is put forward. By combining multiple bits of message, it can be expressed in file form., and the message selection and upload mechanism is adopted, which eliminates the necessity of “0” file uploading so as to greatly reduce the amount of data uploaded to the server.; secondly, in order to achieve the error-free decoding of multi-bit covert channel, a new synchronization technique is proposed, which uses files with different time stamps and sorts them to improve the order of data transmission; finally, the validity of the algorithm is verified by testing the performance of the proposed convert channel algorithm in the cloud storage service SugarSync and BaiduYun.