Towards Dynamic Service Level Agreement Negotiation: An Approach Based on WS-Agreement

In Grid, e-Science and e-Business environments, Service Level Agreements are often used to establish frameworks for the delivery of services between service providers and the organisations hosting the researchers. While this high level SLAB define the overall quality of the services, it is desirable for the end-user to have dedicated service quality also for individual services like the orchestration of resources necessary for composed services. Grid level scheduling services typically are responsible for the orchestration and co-ordination of resources in the Grid. Co-allocation e.g. requires the Grid level scheduler to coordinate resource management systems located in different domains. As the site autonomy has to be respected negotiation is the only way to achieve the intended co-ordination. SLAB emerged as a new way to negotiate and manage usage of resources in the Grid and are already adopted by a number of management systems. Therefore, it is natural to look for ways to adopt SLAB for Grid level scheduling. In order to do this, efficient and flexible protocols are needed, which support dynamic negotiation and creation of SLAB. In this paper we propose and discuss extensions to the WS-Agreement protocol addressing these issues.