In Reporting Services, role assignments determine access to stored items and to the report server itself. A role assignment has the following parts:
A securable item for which you want to control access. Examples of securable items include folders, reports, and resources.
A user or group account that can be authenticated by Windows security or another authentication mechanism.
Role definitions that define a set of tasks. Examples of role definitions include System Administrator, Content Manager, and Publisher.
Role assignments are inherited within the folder hierarchy. The role assignment that is defined for a folder is automatically inherited by all reports, shared data sources, resources, and subfolders contained within that folder. You can override inherited security by defining role assignments for individual items. All parts of the folder hierarchy must be secured by at least one role assignment. You cannot create an unsecured item or manipulate settings in a way that produces an unsecured item.
The following diagram illustrates a role assignment that maps a group and a specific user to the Publisher role for Folder B.
Role-based security in Reporting Services is organized into the following levels:
Item-level role assignments control access to reports, folders, report models, shared data sources, and resources in the report server folder hierarchy. Item-level role assignments are defined when create a role assignment on a specific item or on the Home folder.
System role assignments authorize operations that are scoped to the server as a whole (for example, the ability to manage jobs is a system level operation). A system role assignment is not the equivalent of a system administrator. It does not confer advanced permissions that grant full control of a report server.
A system role assignment does not authorize access to items in the folder hierarchy. System and item security are mutually exclusive. For any given user or group, you might need to create both a system-level and item-level role assignment to provide sufficient access to a report server.
The users or group accounts that you specify in role assignments are domain accounts. The report server references, but does not create or manage, users and groups from a Microsoft Windows domain (or another security model if you are using a custom security extension).
Of all the role assignments that apply to any given item, no two can specify the same user or group. If a user account is also a member of a group account, and you have role assignments for both, the combined set of tasks for both role assignments are available to the user.
When you add a user to a group that is already part of a role assignment, you must reset Internet Information Services (IIS) for the new role assignment to take effect for that user.
By default, predefined role assignments are implemented that allow local administrators to manage the report server. You must add additional role assignments to grant access to other users.
For more information about the predefined role assignments that provide default security, see Using Predefined Roles.