Cloud computing is characterized by efficient provision of services and access to shared resources through its pay-per-use model. The service brokers in this architecture mediate among cloud users and cloud service providers to redirect requests to appropriate data centers while aiming at minimization of response time and monetary cost for cloud users. For selection of data centers, the optimization techniques incur large overhead during execution of applications. Consequently, the recent brokering approaches resort to heuristics which do not guarantee optimal solutions in terms of response time and cost that are pivotal for executing compute intensive applications in a cloud environment. In this paper, we propose multi-objective service brokering with availability-based load balancing (MOSB_ALB) approach that minimizes response time and monetary cost for efficient low-cost provision of services in a cloud environment. The MOSB_ALB approach performs static and dynamic selection of data centers while using availability-based load balancing for distributing load among virtual machines. The static computation of data center index incorporates MOEA/D algorithm and uses z-score values corresponding to indexes in optimal solutions. The dynamic computation of data center indexes uses criteria based on weights and allocation counts. The experimentation performed through a large number of configurations shows that the MOSB_ALB approach outperforms existing well-known cloud service brokering approaches by improving cumulative response time with a speedup factor of 2.19, along with a significant reduction of monetary cost.

云计算的特点是有效提供服务，并通过按使用付费模式来访问共享资源。此体系结构中的服务代理在云用户和云服务提供商之间进行中介，以将请求重定向到适当的数据中心，同时旨在最小化云用户的响应时间和金钱成本。对于数据中心的选择，优化技术会在应用程序执行期间产生大量开销。因此，最近的代理方法求助于启发式算法，该方法无法保证在响应时间和成本方面的最佳解决方案，这对于在云环境中执行计算密集型应用程序至关重要。在本文中，我们建议使用基于可用性的负载平衡（MOSB_ALB）方法的多目标服务代理，该方法可将响应时间和金钱成本最小化，以便在云环境中有效地低成本提供服务。MOSB_ALB方法执行数据中心的静态和动态选择，同时使用基于可用性的负载平衡在虚拟机之间分配负载。数据中心指标的静态计算结合了MOEA / D算法并使用与最佳解决方案中的索引对应的z得分值。数据中心索引的动态计算使用基于权重和分配计数的标准。通过大量配置进行的实验表明，MOSB_ALB方法通过以2.19的加速因子改善累积响应时间，并显着降低了货币成本，从而胜过了现有的众所周知的云服务代理方法。