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A Java EE application may consist of several components that can be deployed on to into different containers such as WEB container, EJB container, WebServices container in a JEE5 server. This kind of deployment allows multi-tier applications that interact with one another to perform a given user task. Multi-tier JEE5 applications can be secured by properly selecting authenticating mechanisms and designing authorization levels or roles. If the application components use declarative security management, the authentication and authorization aspects are declared in corresponding JEE5 deployment descriptors. The declared security roles or levels are mapped to real security roles or levels in the geronimo deployment plans through security realms. In apache geronimo , the security realms abstract away authentication and authorization aspects of the application components. The authentication and authorization together enable access control for the various components of the application.
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