ABSTRACT
This chapter presents a brief explanation of the services and implementation of models of cloud computing in order to promote a discussion of the strong and weak points of each. It provides a discussion about the aspects to help the user in the process of building an e-Science service in the cloud. The chapter introduces the evaluation criteria to guide the user in making the correct choice from the available options. It discusses the main public cloud providers, and their chief characteristics. The chapter also introduces the cost efficiency evaluation to support the user in assessing both price and performance when choosing a provider. To create a service to execute scientific applications in the cloud, the user needs to choose an adequate cloud environment. The software-as-a-service model is commonly used to deliver e-science services to users. This kind of portal is used to run standard scientific applications, and no customization is allowed.
