A Survey on Bilateral Multi-Round Cloud-SLA Negotiation Strategies

Today, static cloud markets where consumers purchase services directly from providers are dominating. Thus, consumers neither negotiate the price nor the characteristics of the service. In recent years, providers have adopted more dynamic trading mechanisms, as e.g. Amazon's EC2 platform shows: In addition to the reservation marketspace and the on-demand marketspace, Amazon offers a spot marketspace where consumers can bid for virtual machines. This spot marketspace was extended with spot blocks, and recently Amazon reworked the bidding options. In addition, other cloud providers, such as Virtustream, adopt dynamic trading mechanisms. The scientific community envisions autonomous multi-round negotiations for realizing future cloud marketspaces. Consequently, consumers and providers exchange offers and counteroffers to reach an agreement. This helps providers increase the utilization of their datacenters, while consumers can purchase highly customized cloud services. In the paper at hand, we present a survey on multi-round bilateral negotiation strategies for trading cloud resources. Thus, we analyzed peer-reviewed articles in order to identify trends, gaps, similarities, and the scope of such negotiation strategies. In addition, we surveyed the formalism that the scientific community uses to describe such strategies. Based on these findings, we derived recommendations for creating and documenting bilateral multi-round negotiation strategies to foster their implementation in the industry.