Encryption of sensitive data is commonly used to preserve confidentiality and integrity. The problem with encrypting data is we have to decrypt it for applying operations on files such as altering a word document or querying a statistical database containing financial data. Decrypting the data will leave it vulnerable. If we want to perform conditional based search queries in an encrypted data entire data should be decrypted to perform it, unless an order preserving scheme is used. There is no homomorphic encryption scheme which will allow us to perform conditional based queries without decrypting the entire data. In mathematical term homomorphic describes the changeover of one data set into another upholding the association between elements in both sets. Order Preserving Encryption (OPE) schemes are used extensively used in cryptography because of their usage in database design. But there is a chances of inference attack in case of OPE. In this paper we had proposed and implemented a technique which will allow to perform conditional based search queries in the data encrypted using any encryption algorithm with log(n) decryption, thereby reducing complexity.
B. Venugopal and Greeshma Sarath, “A Novel Approach for Preserving Numerical Ordering in Encrypted Data”, in 2016 International Conference on Information Technology (ICIT), Bhubaneswar, India, 2016.