Conclusion

Cloud computing is currently an emerging paradigm that envisions a new paradigm of "everything-as-a-service," hence, virtualizes physical resources, infrastructure, and applications which are being provided through service provisioning in the cloud. The growing adoption of cloud services suggests clear and distinct promises within the cloud industry. Due to the increasing number of cloud providers and the variety of service offerings, it has become difficult for new customers to choose the best provisioned services. Therefore, we have clearly identified service provisioning techniques, mechanisms, and several approaches that must be understood to evaluate the provisioned services in terms of user requirements and costs. Hence, continuous service provisioning that satisfies the user requirements is a mandatory feature for the cloud user and vitally important in cloud computing service offerings. Therefore, we reviewed the state-of-the-art service provisioning objectives, essential services, topologies, user requirements, necessary metrics, and pricing mechanisms. In addition, we synthesized and summarized different provisioned techniques, approaches, and models through a comprehensive literature review. Moreover, a proposal of the thematic taxonomy of cloud service provisioning is presented. Finally, open research issues are categorized and identified for future research directions.