What access control service determines what an authenticated user can do within a system?

The choice of authorization is fundamentally important in access control services as it specifically defines and regulates what an authenticated user is permitted to do within a system. After a user successfully goes through the authentication process—verifying their identity through credentials—authorization takes center stage by evaluating the user's permissions and roles.

This means that once users are authenticated, the system determines their access level based on predefined policies, roles, or attributes associated with their identities. For instance, in a corporate environment, an employee might have access to sensitive files within their department but could be restricted from accessing other departments’ information.

This capability not only safeguards sensitive information but also ensures that users can perform their necessary functions without compromising security. While authentication validates who a user is and accounting logs activities for auditing, it is authorization that ultimately dictates the specific actions a user may execute within the system.