With the fast evolution of networks and Internet, appeared the concept of the Cloud, the requirements in terms of safety become more and more essential. This requires the introduction of advanced authentication methods, access control and identity management, while respecting the constraints of the services offered by this evolution, such as data exchange capacity and resources of terminals. The aim of our work is to propose cloud security architecture to be able to establish secure sessions between the nodes of a cluster in the cloud, and allow to different users a secure access to their data.