UAA: User authentication agent for managing user identities in cloud computing environments

Cloud computing is the realization for a long-held dream of computing as utility of establishment of on-demand IT services. The considerable specifications of this emerging technology have attracted attentions of many users and enterprises in various industries. However, there are some considerable concerns that reduce reliability of cloud-based services. Managing user identities in clouds is one of the most challenging security issues that has led to many performed researches in this area. Hence, an agent-based user authentication model has been presented in this paper to enhance security of cloud computing environments. A unique extension has been provided in the proposed model is to identify the ownership of private individual devices and to establish a reasonable and logical dependency between cloud servers and clients. Furthermore, a provisional access permission algorithm has been presented for un-registered devices to investigate and verify authenticity and correctness of one-time access requests by a higher level of security in comparison with current models. The proposed model has been introduced and evaluated regarding to three main parameters: performance, security, and scalability. The analysis of user authentication agent shows that this model enhances the rate of security and reliability in cloud computing environments without affecting the rate of energy and time consumption, and scalability.