Improving Data Security in Cloud Storage Services

Abstract

Cloud storage services have changed the way used to manage and interact with data outsourced to public domains. With these services, multiple subscribers can collaboratively work and share outsourced data without any concerns about their data consistency, availability and reliability. Examples of these services include Dropbox, Box.net, UbuntuOne or JungleDisk. Although these cloud storage services offer seductive features, many customers are not rushing to move their data into these services. Since data stored in these services is under the control of service providers which makes it more susceptible to security risks. Therefore, using cloud storage services for storing users data depends mainly on whether it is sufficiently secure or not. From the way cloud storage services are constructed, we can notice that these storage services don't provide users with sufficient levels of security leading to an inherent risk on users' data from external and internal attacks. To deal with these security problems, this paper proposes a novel data sharing mechanism that simultaneously achieves data confidentiality, fine-grained access control on encrypted data and user revocation by combining ciphertext policy attribute-based encryption (CP-ABE), and proxy re-encryption (PRE).