The number of both service providers operating in the cloud market and customers consuming cloud-based services is constantly increasing, proving that the cloud computing paradigm has successfully delivered its potential. Nevertheless, the unceasing growth of the cloud market is posing hard challenges on its participants. On the provider side, the capability of orchestrating resources in order to maximise profits without failing customers’ expectations is a matter of concern. On the customer side, the efficient resource selection from a plethora of similar services advertised by a multitude of providers is an open question. In such a multi-cloud landscape, several research initiatives advocate the employment of software frameworks (namely, cloud resource orchestration frameworks - CROFs) capable of orchestrating the heterogeneous resources offered by a multitude of cloud providers in a way that best suits the customer’s need. The objective of this paper is to provide the reader with a systematic review and comparison of the most relevant CROFs found in the literature, as well as to highlight the multi-cloud computing open issues that need to be addressed by the research community in the near future.

中文翻译：

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多云环境中的云资源编排：现有框架的系统回顾

在云市场上运营的服务提供商和使用基于云的服务的客户的数量都在不断增加，这证明了云计算范例已成功地发挥了其潜力。然而，云市场的持续增长给参与者带来了严峻的挑战。在提供商方面，协调资源以最大程度地提高利润而又不辜负客户期望的能力是一个值得关注的问题。在客户方面，从众多提供商提供的大量类似服务中选择有效的资源是一个悬而未决的问题。在这种多云的环境中，一些研究计划主张采用软件框架（即，云资源编排框架（CROF），能够以最适合客户需求的方式编排众多云提供商提供的异构资源。本文的目的是为读者提供文献中最相关的CROF的系统综述和比较，并着重强调研究领域需要在不久的将来解决的多云计算开放性问题。未来。