A hybrid model for cloud providers and consumers to agree on QoS of cloud services

This paper describes a new agenda based approach which facilitates multi-issue negotiation process between service consumer and service provider over the quality of service (QoS) requirements in cloud services. We assume that the order of agenda (issues) has impact on the negotiation outcome, but a group of service consumers and providers may have conflicting preferences over the importance of issues. In a multiple-issue negotiation process it is difficult to reach an optimal outcome when their preferences and the relative importance of their associated issues are not known to each other. The proposed agenda based preference ordering approach helps consumers and providers to reach a consensus over the issues and to construct a common preference sequence to improve the efficiency of the issue-by-issue negotiation outcome. Consequently, a co-evolutionary negotiation model based on the result of preference ordering approach is introduced for the agents to negotiate and reach an agreement, if there is any. The contribution of the research is a new mechanism that is able to formulate issue sequence along with a co-evolutionary negotiation approach that can effectively facilitate negotiation over QoS issues in cloud computing. Finally, a case study is provided to illustrate the proposed approach.