Enhanced Schmidt-Samoa cryptosystem for data confidentiality in cloud computing

Cloud computing provides IT services like computation, storage, networking, and software to the users. Cloud storage services allows users to access the data anywhere and at anytime, under the supervision of cloud service provider (CSP). Protecting the data against data breaches in the cloud is still a challenging issue for CSP. Public key cryptographic techniques are widely used to ensure authenticity, confidentiality, and non-repudiation. Schmidt-Samoa cryptosystem (SSC) is a public key cryptosystem, which depends on the resistance of integer factorisation. While implementing SSC in the cloud, the cryptosystem consumes more time for performing encryption and decryption. In this paper, we propose an enhanced Schmidt-Samoa (ESS) public key cryptosystem to address this problem. The ESS cryptosystem composes with four prime numbers, which increase the complexity to break the cryptosystem compared to SSC. The experimental results with variable file size and key size also proved that the time required to perform the data encryption and decryption in ESS is lower and the time required to perform cryptanalysis in ESS is higher compared with SSC. Thus, the ESS cryptosystem is highly secured, and improves data confidentiality.