Efficient Schemes for Anonymous Yet Authorized and Bounded Use of Cloud Resources

In this paper we introduce

anonymous yet authorized and bounded

cloud resource schemes. Contrary to many other approaches to security and privacy in the cloud, we aim at hiding behavioral information, i.e.

consumption patterns

, of users consuming their cloud resources, e.g. CPU time or storage space, from a cloud provider. More precisely, users should be able to purchase a contingent of resources from a cloud provider and be able to anonymously and unlinkably consume their resources till their limit (bound) is reached. Furthermore, they can also reclaim these resources back anonymously, e.g. if they delete some stored data. We present a definition of such schemes along with a security model and present an instantiation based on Camenisch-Lysyanskaya signatures. Then, we extend the scheme to another scheme providing even more privacy for users, i.e. by even hiding the issued resource limit (bound) during interactions and thus providing full anonymity to users, and present some useful extensions for both schemes. We also support our theoretical claims with experimental results obtained from an implementation that show the practicality of our schemes.