Green-Aware High Availability Provisioning for Cloud Computing Applications

云计算是一种新兴的计算模式，它支持按需和可扩展的计算资源供应。云计算以其灵活性、高效性和为云用户降低成本的能力，正日益获得业界的认可。云计算为托管非关键IT服务提供了高效的解决方案，但在可靠性和高可用性方面还不能满足电信和关键实时应用的要求。主要的云提供商，如亚马逊，只是确保他们以服务形式提供的虚拟资源的可用性。从云租户的角度来看，他们主要关心的是部署在云中的应用程序的高可用性。该研究项目的第一个目标是定义一个高可用性解决方案，以弥合云用户的愿望和云提供商提供的产品之间的差距。在云计算的背景下，高可用性提出了一些与绿色计算相冲突的要求，绿色计算的目标是有效地利用资源并减少云的环境足迹。特别是，虽然高可用性有利于冗余和使用备用实体来消除单点故障，但绿色计算鼓励整合资源以最大限度地提高利用率。这就引入了一个多维优化问题。这项研究项目的第二个目标是将绿色意识纳入为实现第一个目标而定义的房委会解决方案中。

Cloud computing is an emerging computing paradigm, which enables an on-demand and scalable provision of computing resources. Cloud computing is increasingly gaining industrial acceptance due to its flexibility, efficiency and its ability to reduce the costs for the Cloud users. Cloud computing provides an efficient solution for hosting non-critical IT services, but it does not yet meet the telecom and critical real-time applications requirements in terms of dependability and high availability. Major Cloud providers, such as Amazon, just ensure the availability of the virtual resources they are offering as a service. From the perspective of the Cloud tenants, the main concern is the high availability of their applications deployed in the Cloud. The first objective of this research project is to define a high availability solution that bridges this gap between the Cloud users' aspirations and the Cloud providers' offerings. In the context of Cloud computing, high availability imposes certain requirements that are conflicting with the Green computing, which aims at an efficient resource utilization and reduction of the environmental footprint of the Clouds. In particular, while high availability favors redundancy and the use of standby entities to eliminate single points of failures, Green computing encourages the consolidation of resources to maximize utilization. This introduces a multi-dimensional optimization problem. The second objective of this research project is to incorporate Green-awareness into the HA solutions defined to achieve the first objective.