The volume-hiding encrypted multi-map(EMM)scheme is able to prevent attackers from inferring plaintext through the volume leakage,but existing solutions have problems with large storage and search computational costs.Based on the characteristic that the volume of the searched data often follows Zipf's law,a hierarchical volume-hiding EMM scheme was proposed.Compared to the plain scheme that filled all keys'volumes equally,converting the filling of the overall data into the filling of multiple sub-data blocks could reduce storage costs,and also achieved constant level complexity query overhead.Security analysis shows that the proposed scheme can achieve hidden matching volume without loss of query results.Simulation results show that compared with the most efficient scheme XorMM,the pro-posed scheme can increase the storage overhead by 10%,reduce the search computing overhead by 90%,and significant-ly improve the search efficiency.
维普
万方数据