The Research Of Proxy-based Encryptions On Cloud Database

Cloud database is a new form for outsourcing data which is a novel achievement under the background of Saa S(Software as a Service).For the sake of data security,both enterprises and individuals are willing to outsource cipher-texts.However,the encryption will make data inapplicable and greatly reduce the interactions between client and service.Therefore,the scholars of academia and industry attempt to study functional encryptions directly on cipher-texts.Encrypted database is one typical cryptography query application scenarios which combines various of attribute-based encryptions.This paper studies the related papers and open source code in the domain of encrypted database and has done three aspects of the work innovation.The main work and contributions of this article are as follows:· We propose a database-oriented middle-ware encryption algorithm framework(CPD,the client-proxy-database framework).It divides cipher-text columns into main column for symmetric decryption and auxiliary columns for multiple operations,and utilizes middle-ware software to rewrite or append SQL statements.The framework does not rely on secondary processes or user-dened functions,so it benets from a non-extended cloud database scenario.· We propose a wildcard-supported fuzzy searching encryption(wc FSE)which is implemented under the CPD framework to handle complex queries with`like' clause.It constructs two types of functional columns,the column with locality sensitive hashing for similarity searching and the columns with bloom-lter for maximum substring matching.And the adaptive rewriting method helps manage complex wildcard situations to t fuzzy searching.· We propose a fractional mutable order-preserving encryption(Fm OPE)which is implemented under the CPD framework to handle comparison operations on cipher-texts.By means of fractional coding method,the algorithm greatly alleviates the conict between cipher-texts persistence and mutability requirements.We compare several binary tree balance strategies(AVL tree,Red-Black tree,Scapegoat tree,Splay tree and Treap)and adopt some optimizations to achieve good performance and eciency.In summary,this paper presents a general solution for cloud database outsourcing problem which cannot support UDF extensions,and propose two encryptions for this framework.We discuss the security and applicability of our scheme and the extensive experiments show that the proposed methods have good performance.