Cloud Computing is an emerging technology, providing attractive way of hosting and delivering services over the Internet. Many organizations and individuals are utilizing Cloud services to share information and collaborate with partners. However, Cloud provides abstraction over the underlying physical infrastructure to the customers, that raises information security concerns, while storing data in a virtualized environment without having physical access to it. Additionally, certain standards have been issued to provide interoperability between users and various distributed systems(including Cloud infrastructures), in a standardized way. However, implementation and interoperability issues still exist and introduce new challenges. This thesis explores the feasibility of securing data in a cloud context, using existing standards and specifications, while retaining the benefits of the Cloud. The thesis provides a view on increasing security concerns of moving to the cloud and sharing data over it. First, we define security and privacy requirements for the data stored in the Cloud. Based on these requirements, we propose the requirements for an access control system in the Cloud. Furthermore, we evaluate the existing work in the area of currently available access control systems and mechanisms for secure data sharing over the Cloud, mostly focusing on policy enforcement and access control characteristics. Moreover, we determine existing mechanisms and standards to implement secure data sharing and collaborative systems over the Cloud. We propose an architecture supporting secure data sharing over the untrusted Cloud environment, based on our findings. The architecture ensures policy based access control inside and outside Cloud, while allowing the benefits of Cloud Computing to be utilized. We discuss the components involved in the architecture and their design considerations. To validate the proposed architecture, we construct the proof of concept prototype. We present a novel approach for implementing policy based access control, by achieving interoperability between existing standards and addressing certain issues, while constructing the system prototype. Furthermore, we deploy our solution in the Cloud and perform the performance tests to evaluate the performance of the system. Finally, we perform a case study by utilizing our system in a real-life scenario. To do this we slightly tailor our solution to meet specific needs. Overall, this thesis provides a solid foundation for the policy enforcement and access control mechanisms in the Cloud-based systems and motivates further work within this field.
|Date of Award||31 Oct 2013|
|Supervisor||Milan Petkovic (Supervisor 1) & R.P. (Paul) Koster (External coach)|