International Journal of Applied Engineering Research ISSN 0973-4562 Volume 12, Number 13 (2017) pp. 3908-3913 © Research India Publications. http://www.ripublication.com 3908 Trust Evaluation Scheme for Cloud Data Security using Fuzzy based Approach Muthusenthil Balasubramanian 1 and Hyunsung Kim 2 1 Information Security Research Institute, Wookyoung Information Technology, Daegu Associate Professor, Computer Science and Engineering, Valliammai Engineering College, India. 2 Department of Cyber Security, Kyungil University, Korea. Department of Mathematical Sciences, University of Malawi, Zomba, Malawi. 1 ORCID: 0000-0003-2186-9453, 1 ResearcherID: F-5019-2013, 1 Scopus Author ID: 7410126657 Abstract Cloud computing provides a services for sharing and storing the data. Both cloud server and trusted authority are semi- trusted party. The generation of trust value for cloud server and trust authority is a tedious process. Many researchers proposed different methods for generating trust value and it is still in open research. So, we propose a trust evaluation scheme for cloud data security using fuzzy based approach. By using fuzzy based approach, the trust value is generated. After obtaining the trust value, data can be re-encrypted by a trusted authority for security. After re-encryption the data are stored in cloud server which then can be shared and stored securely in cloud. Keywords: Cloud Security, Trust Evaluation, Re-Encryption, Trust Authority, Fuzzy Control INTRODUCTION Cloud computing is an emerging computing paradigm and a novel business model. It reduces cost and avoids the expenses by pay as you go model [1-2]. From data center [3] the cloud services are deployed and operated by the users. For cloud providers and cloud consumers [4, 8], cloud computing provides the speed for data sharing. By information and communications technology, pertinent data is accessed in a cloud environment. Instead of stored data, only on a local server/computer, remote hardware is used in cloud environment. At low cost, high increase in storage data is available in cloud environment. There are some risks concerning privacy and resilience in current cloud computing model. Lack of knowledge about cloud service selection for cloud consumer and provider is the main reason for risks in privacy. The trust based assumption in service selection satisfies the customer believes and it fulfills consumer’s requirement. This is known as trustworthiness. Trust means an act of faith; confidence and reliance in something that’s expected to behave or deliver as promised. Consumers get more confident and reliance for the care for their data when better trustworthiness is provided by the cloud service. It is the main consideration by the consumers. As discussed in [1], reputation degree is the main dependent factor of trustworthiness. So along with reputation we have to consider more trust factors while making decision in cloud service selection. For cloud service selection, there are enormous challenges. Thus there is no standardized metric system, it is difficult to compare trustworthiness of cloud services and also it is too expensive and time consuming to evaluate trustworthiness of cloud services. The main objective of the paper is to create a trust model framework for data sharing and storage by trust evaluation service authority. The trust value is generated for the cloud servers and trusted authority. The parameter value of cloud server and trusted authority is collected from the cloud benchmark service. The rule generator computes the trust value based on the history and sends it to the cloud user. The cloud user will select the cloud server based on the requirement. The rest of this paper is organized as follows. We review the trust model framework in section 2. In section 3, we propose a trust evaluation scheme using fuzzy based approach. In section 4 we discuss the experimental analysis. Finally we conclude this paper in section 5. RELATED WORKS Fan et al. in [16] proposed a novel trust management framework for multi-cloud environments based on trust service providers (TSPs). In the paper, the problems of trust management in multi-cloud environment are addressed based on a set of distributed TSPs. The trust related services are provided to cloud participants by cloud providers, cloud service providers, cloud users. In cloud the TSPs are