Dependable Storage in the Intercloud

The cloud computing paradigm with its elastic payas-you-go model, “infinite” scalability and “always-on” availability arguably changes the landscape of services and systems. However, so far, cloud proliferation has not lived up to expectations in the enterprise segment. Often cited issues include confidentiality and integrity, but also reliability and consistency. In this paper, we argue for the Intercloud as the second layer in the cloud computing stack, with the goal of building more dependable cloud services and systems. In the Intercloud layer, we foresee client-centric distributed protocols to complement more provider-centric, largescale ones in the (Intra)cloud layer. These client-centric protocols orchestrate multiple clouds to boost dependability by leveraging inherent cloud heterogeneity and failure independence. We also discuss the design of Intercloud storage, which we currently are implementing, as a primer for dependable services in the Intercloud. Intercloud Storage precisely addresses and improves the CIRC attributes (confidentiality, integrity, reliability and consistency) of today’s cloud storage services.