# A Trusted Multi-Cloud Brokerage System for Validating Cloud Services Using Ranking Heuristics
## 1 Introduction  
Cloud computing enables users to access services such as infrastructure, applications, and platforms on an on-demand basis [1]. Typically, users interact with cloud services through a single cloud service provider's interface. However, in today's dynamic and open digital ecosystem, relying solely on a single vendor often fails to meet diverse user requirements, particularly in terms of service quality. As a solution, multi-cloud computing has emerged, offering a broader range of services with greater flexibility. This paradigm supports the development of highly scalable and reliable service environments, allowingusers to access best-in-class services across multiple providers. Moreover, multi-cloud computing addresses critical concerns such as vendor lock-in, cost-performance optimization, data privacy, and regulatory compliance. To further streamline service selection and delivery, intelligent cloud brokers [2] have been introduced. These brokers operate at both the producer and consumer levels, facilitating the provisioning of high-quality, validated services from multi-cloud environments. In this context, the intelligent cloud broker, as proposed in this work, is responsible for validating and verifying cloud services, thereby enhancing trust and efficiency in service recommendations.  
In general, the validation and verification of a cloud services are intended to provide the most reliable, robust, and secure services in accordance with customer expectations. This also assumes an ability to continuously offer cloud services even during uncertain interferences. In addition, the validation and verification of a service is usually determined using a number of multifaceted indicators which can be performed by the intelligent cloud brokers. The existing brokers perform the service selection based on either considering the Service Level Agreements (SLA) or Quality of Services (QoS's) factors. In addition to that, the users' feedback and ratings of the services can also be used for the identification of the right services by applying a number of techniques. All these processes are carried out for the single cloud provider only. No such attempts have been found with respect to multi-cloud computing. In this paper, an intelligent cloud broker with self-healing properties is proposed to perform the task of service validation and verification for a multi-cloud environment.  
In summary, the key contributions of this paper are as follows:  
1. Proposal of an Intelligent Cloud Broker--Introduces a novel intelligent cloud broker that extracts trust factors from a multi-cloud environment to enhance service selection processes;
2. Trust Prediction and Clustering--Implements a trust prediction mechanism by validating and verifying extracted trust factors, followed by clustering services using a service ranking algorithm;
3. Service Recommendation Framework--Provides a robust service recommendation system that incorporates validation reports to ensure reliability and accuracy.  
The rest of this paper is organized as follows: In Section 2, we recount the related work in multi-cloud service recommendation system. Section 3 explores the proposed system, which performs the validation and verification process by considering the thirteen service trust factors. The experimental works with the results and discussion are presented in Section 4. Finally, Section 5 concludes our proposal with future directions.