A standards-based approach for negotiating service QoS with cloud infrastructure providers

Up to now, dynamic electronic Service Level Agreements are rarely used in Clouds to define and agree upon the QoS the Cloud provider will deliver to its customers. Instead, Cloud infrastructures are offered to customers in a best effort approach with limited guarantees and compensations. However, a service provider intending e.g. to extend its own resources dynamically with Cloud resources in case of peak demands of its customers needs reliable Service Level Agreements with the Cloud infrastructure providers. The European project OPTIMIS is providing a toolkit enabling service providers (SP) and infrastructure providers (IP) to achieve a defined QoS by optimising their respective services in a multi Cloud environment. We present in this paper results of our work that go beyond the limited, static QoS offerings of current Cloud providers in serveral dimensions: open and standards-based, fine-grained expression of requirements as necessary, dynamic electronic SLAs covering aspects like cost, security, legal requirements for data-placement, eco-efficiency and more.