Recently, cloud computing becomes one of the main orientations of many researchers and companies in the IT area. Therefore, a huge number of cloud services have been developed. Because of the diversity and heterogeneity in providing these services, it is urgently needed to develop a unified cloud ontology. Such ontology can classify these services appropriately and participate as a mapping layer to present such services in a unified description format. Although many studies have been conducted to build cloud ontologies, they have adopted the cloud service layers-based structure. On the other hand, the existing cloud services may involve functionalities from different layers due to the continual increase in the complexity of customer demands. Unfortunately, there are no clear relations to organize the interventions among these layers. Therefore, such services may be difficult to be classified into a specific cloud service layer. Additionally, the layers-based structure of ontologies represents an obstacle to address important issues, such as cloud service recommendation. Despite there are few cloud service functionality-based cloud ontologies, they suffer from many overlaps, lack of semantic relations, or poor granularity of concepts. Also, all the existing cloud ontologies (i.e., layers-based and functionality-based) lack important criteria, such as completeness, consistency, conciseness, clarity, preciseness, and granularity. In this paper, a comprehensive cloud ontology called CloudFNF has been proposed to overcome such drawbacks. According to the structure of the proposed ontology, cloud services are classified as functionality-based instead of layers-based. Also, non-functional features of cloud services (i.e., configuration and QoS features) are considered to enable services of the same functionalities to be ranked efficiently. Based on our previously suggested cloud ontology evaluation framework, our proposed cloud ontology has been evaluated compared to the most related cloud ontologies. The evaluation results show that the proposed CloudFNF ontology outperforms the other ontologies.

最近，云计算已成为IT领域许多研究人员和公司的主要方向之一。因此，已经开发了大量的云服务。由于提供这些服务的多样性和异构性，迫切需要开发统一的云本体。这样的本体可以适当地对这些服务进行分类，并作为映射层参与以统一的描述格式呈现这样的服务。尽管已经进行了许多研究来构建云本体，但是他们已经采用了基于云服务层的结构。另一方面，由于客户需求的复杂性不断增加，现有的云服务可能涉及来自不同层的功能。不幸的是，在这些层之间没有明确的关系来组织干预措施。因此，此类服务可能难以归类为特定的云服务层。此外，基于层的本体结构是解决重要问题（如云服务推荐）的障碍。尽管基于云服务功能的云本体很少，但它们却存在许多重叠，缺乏语义关系或概念的粒度不佳的问题。而且，所有现有的云本体（即基于层和基于功能的）都缺少重要的标准，例如完整性，一致性，简洁性，清晰度，精确性和粒度。在本文中，提出了一种名为CloudFNF的综合云本体，以克服这些缺陷。根据提出的本体的结构，云服务被分类为基于功能而不是基于层。也，云服务的非功能性特征（即配置和QoS功能）被认为可以有效地对相同功能性的服务进行排名。基于我们之前提出的云本体评估框架，我们对提出的云本体进行了评估，并与最相关的云本体进行了比较。评估结果表明，提出的CloudFNF本体优于其他本体。