Section: Software and Platforms

CSLA

Participants : Thomas Ledoux [correspondent] , Yousri Kouki.

Service-level agreement, Cloud computing, elasticity

Verifying non-functional properties like performance, dependability, energy consumption and economical costs of Clouds is challenging today due to ad-hoc management in terms of Quality-of-Service (QoS). We believe that a differentiating element between Cloud computing environments will be the QoS and the service-level agreement (SLA) provided by the Cloud.

CSLA, the Cloud Service Level Agreement language, allows the definition of SLA properties for arbitrary Cloud services (XaaS). CSLA addresses QoS uncertainty in unpredictable and dynamic environment and provides a cost model of Cloud computing. Besides the standard formal definition of contracts – comprising validity, parties, services definition and guarantees/violations – CSLA is enriched with features, such as QoS degradation and an advanced penalty model, thus introducing fine-grained language support for Cloud elasticity management [13] .

CSLA is available at http://www.emn.fr/z-info/csla .