A Novel Fully Homomorphic Encryption Scheme Bsed on LWE  

作　　者：DING Yong LI Xiumin Lü Haifeng LI Xinguo 

机构地区：[1]School of Mathematics and Computing Science, GuangxiKey Laboratory of Cryptography and Information Security, Guilin University of Electronic Technology, Guilin 541004, Guangxi, China [2]Guangxi Experiment Center of Information Science, Guilin University of Electronic Technology, Guilin 541004,Guangxi, China [3]Shenzhen Digital TV National Engineering Laboratory Co.Ltd., Shenzhen 518057,Guangdong, China

出　　处：《Wuhan University Journal of Natural Sciences》2016年第1期84-92,共9页武汉大学学报（自然科学英文版）

基　　金：Supported by the National 863 Project(2012AA011705);Guangxi Natural Science Foundation(2013GXNSFBB053005);Guangxi Science Research&Technology Development Project(14124004-4-10);Guangdong Natural Science Foundation(2014A030313517);Guangxi Experiment Center of Information Science Foundation

摘　　要：Although the learning with errors（LWE）-based full homomorphic encryption scheme was the first example of deviation from the original Gentry＇s blueprint, the scheme did not give detailed conversion process of circuit layer structure, and must rely on bootstrapping technique to achieve full homomorphism. Therefore, through modifying the re-linearization technique proposed by the above scheme, a technique called non-matrix key switching is presented, which includes key switching with re-linearization and pure key switching. The complex matrix operations of existing key switching technique are removed. Combining this technique with modulus switching, a （leveled） fully homomorphic encryption scheme without bootstrapping from LWE is constructed. In order to make circuit layer structure clear, the scheme gives detailed refresh door operation. Finally, we use bootstrapping to upgrade arithmetic circuit to any layer, and make the homomorphic computing capability of the scheme have nothing to circuit depth.Although the learning with errors（LWE）-based full homomorphic encryption scheme was the first example of deviation from the original Gentry＇s blueprint, the scheme did not give detailed conversion process of circuit layer structure, and must rely on bootstrapping technique to achieve full homomorphism. Therefore, through modifying the re-linearization technique proposed by the above scheme, a technique called non-matrix key switching is presented, which includes key switching with re-linearization and pure key switching. The complex matrix operations of existing key switching technique are removed. Combining this technique with modulus switching, a （leveled） fully homomorphic encryption scheme without bootstrapping from LWE is constructed. In order to make circuit layer structure clear, the scheme gives detailed refresh door operation. Finally, we use bootstrapping to upgrade arithmetic circuit to any layer, and make the homomorphic computing capability of the scheme have nothing to circuit depth.

关 键 词：fully homomorphic encryption re-linearization key switching modulus switching LWE BOOTSTRAPPING 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]