Report security
Security is both user based and report based. User based security is implemented using system permissions; report-based security is implemented using report permissions. Permissions assigned at the report level apply to all users of the report. A user with system permission access to a report is still subject to report permissions attached to the report by the report owner.
Reporting Services delivers a standard set of user and role permissions that apply to all users and roles. You can assign specific permissions to users and roles at the report and the schedule level. The permission options available depend upon the report type.