Abstract
This research presents a novel and efficient public key cryptosystem known as the
Enhanced Schmidt Samoa (ESS) cryptosystem, proposed to safeguard the data of a single owner
in cloud computing environments. Data storage is a one-time process in the cloud, while data
retrieval is a frequent operation. Experimental results demonstrate that the ESS cryptosystem
offers robust data confidentiality in the cloud, surpassing the security provided by traditional
cryptosystems. The research also introduces a secure cloud framework designed to
accommodate both individuals and organizations accessing applications and data in the
cloud. While individual users may generate and share data, organizations often involve
multiple users in data sharing to support their business processes. In these scenarios, multi-user
data ownership and access management become critical, requiring secure sharing of
cryptographic keys among the authorized users. To address these issues and ensure data
confidentiality in multi-user cloud environments, the Improved Secure Cloud Data Storage
Framework (ISCDSF) is introduced. This research not only enhances data security but also
provides a comprehensive framework for secure data sharing in the cloud, catering to the
needs of both individual users and organizations.