This proposed robust authentication and authorization mechanisms is able to provide better instruments for addressing issues such as isolation and access control in complex cloud environments such as a public or community clouds. In this proposed work, the first contribution is identifying a set of categories for credentials and adapts them to the cloud context. The categories are useful to define what kind of information has to be represented in terms of credentials for a specific system or service, and how this information can be grouped and organized. The second
major contribution is the identification of important elements that have to be considered when adopting or developing a solution for authentication and authorization. This activity motivated the assembling of the authentication and authorization framework which summarizes the concepts that pivot around identities and credentials for cloud computing.