In the cloud environment, the trust and reputation management are major component for providing virtualized and scalable web services from the service providers to the various cloud users. Many existing systems are not effectively encompasses the trusted and reputed cloud services. The trust can be defined as an act of faith, confidence and certainty based on the application. Also it is expected to behave or deliver the service in a proper way as promised by the service providers. The trust should also provide solution for the specific problem due to some uncertainty and vulnerability caused by the constraints in cloud computing. It correlates the security issues and its solutions in cloud. The trust measures are calculated based on the various parameters of the cloud users and the respective service providers. This recommendation kind of metrics provides an effective way of trusted and reputed cloud services in the cloud environment. Trust and reputation is classified based on behavioral metrics such as subjective/objective, transaction-based/opinion-based, complete/localized information and also rank/threshold. Reputation is the assessment of the tasks which ensures the derived trust based services in cloud. Cloud users basically require the reputed system to guarantee the security in cloud services. Thus the reputation which gains the trusted users might be able to access very cheaper services especially in Infrastructure as a service (Iaas), Platform as a service (Paas) and Software as a service (Saas) with a secure cloud environment. While the cloud is incorporated into a variety of application, the trust and reputation are ensuring basically secure services from the corresponding specified service providers. This kind of cloud services breaks the complications in web services and web applications.

Keywords: Cloud computing, Cloud Service providers, Cloud Users, Trust, Reputation, Security.