International Journal of Electrical and Computer Engineering (IJECE) Vol. 6, No. 6, December 2016, pp. 2994~3000 ISSN: 2088-8708, DOI: 10.11591/ijece.v6i6.11972  2994 Journal homepage: http://iaesjournal.com/online/index.php/IJECE A Cloud Based Secure Voting System using Homomorphic Encryption for Android Platform Manish Ranjan, Ayub Hussain Mondal, Monjul Saikia Department of Computer Science and Engineering, North Eastern Regional Institute of Science and Technology, Nirjuli, Arunachal Pradesh, India Article Info ABSTRACT Article history: Received Jul 26, 2016 Revised Nov 8, 2016 Accepted Nov 22, 2016 Cloud based service provider are at its top of its services for various applications, as their services are very much reachable from anywhere anytime in current days. It is responsibility of the company that the Cloud storage is owned and maintained by themselves keeping the data available and accessible, and the physical environment protected and running. Could storage provider seem to be uncertain of confidentiality in many cases, as we need to limit ourselves on trust to a third party. Keeping our sensitive data ready to access any time anywhere with preventing any information leakage is a challenging task. Cryptography in this scenario plays an important role, providing security for information to protect valuable information resources on intranets, Internet and the cloud. In addition, Homomorphic cryptosystem is a form of Cryptography where some specific computation can be performed over the cipher text producing a resultant cipher text which, when decrypted, equals the result of operations carry out on the plaintext. With help of this unique property of homomorphism cryptography we proposed a system to keep sensitive information in encrypted form in the cloud storage/service provider and used those data as whenever we require. The scheme proposed here is designed for a secure online voting system on Android platform and voted information is encrypted and stored those in the cloud. Keyword: Android plateform Cloud computing Cryptography Homomorphic cryptosystem Security and privacy Copyright © 2016 Institute of Advanced Engineering and Science. All rights reserved. Corresponding Author: Monjul Saikia, Departement of Computer Science and Engineering, North Eastern Regional Institute of Science and Technology, Nirjuli-791109, Arunachal Pradesh, India. Email: monjuls@gmail.com 1. INTRODUCTION The meaning of Encryption contains in the word itself, the base "encrypt" can be seen as "en" and "crypt". The meaning of "en" is "to make", and the word "crypt" means hidden or secret. Therefore the meaning of "encrypt" is "to make hidden or secret" [1]. In cryptography, encryption is the process of encoding messages or information in such a manner that only authorized user can interpret it. Hence the scheme of encryption is widely used for secrete communication between two parties. In an encryption scheme a large pseudo-random number called encryption key is generated by an algorithm which is to be used for computation of the cipher text. Later the receiver uses the same key to decrypt to extract the actual message being transmitted (in case of symmetric key encryption). A user without having the same key used for encryption cannot decrypt correctly. The objective of modern cryptography can be classified in four categories: a. Confidentiality: The information is secrete and cannot be recognize by unintended person. b. Integrity: No modification can be done on the information send in between the sender and the intended receiver.