Workflow composition of service level agreements for web services

Service-oriented architecture enables an environment where businesses can expose services for use by their collaborators and their peer organizations. In this dynamic environment, organizations require the use of service level agreements (SLAs) to assure the quality of service (QoS) standards of services provided by their collaborators. In an ad-hoc workflow scenario, a business may need to perform real-time composition of existing services in response to consumer requests. In this work, we suggest that, in parallel to traditional web service composition, the business must also compose the existing SLAs in order to ensure the service levels that must be guaranteed to new consumers. Ultimately, this approach to SLA composition must align with the over-arching principles of the provider and the priorities of the consumer. In this paper, we introduce a model and representations of service level agreement attributes appropriate for managing a service provider's expectations when adding new partners. Our evaluations suggest that the SLA composition can efficiently run concurrently with traditional service composition. (C) 2012 Elsevier B.V. All rights reserved.