A secure dynamic collaboration environment in a cloud context

• We present two conceptual designs that, together, address cloud security concerns.
• We define properties to evaluate and validate the designs against related work.
• The first design surpasses the related work and establishes a security foundation.
• The second design extends the first with detailed access control and auditability.
• The designs are validated through a proof-of-concept prototype.

In recent years, the cloud has emerged as an attractive means for hosting and delivering services over the Internet. This has resulted in a renewed focus on information security in the case where data is stored in the virtual space of the cloud and is not physically accessible to the customer. This paper addresses the increasing security concerns of migrating to the cloud and utilising it for data storage, focusing on securing data in an untrusted cloud environment and ensuring detailed data access control in the cloud. Two Conceptual designs have been devised by exploring and extending the boundaries of existing secure data-storage schemes, and then combining these with well-known security principles and cutting-edge research within the field of cryptography. To further validate the conceptual designs, proof of concept prototypes have been constructed.