File-Based Digital Rights Management

4/8/2010

File-Based Digital Rights Management (FDRM) describes a systematic approach to protecting digital-based content for files such as audio, video, and image files.

The Three parts of a FDRM application

The following three components comprise an FDRM solution for Windows Mobile devices:

  • The Windows Mobile FDRM application programming interface (API), which defines the interface to FDRM-managed content for Windows Mobile devices.
  • FDRM-enabled applications, which access and manage protected content. For developers, the use of the FDRM API within the application enables DRM.
  • FDRM engine, which manages permissions for protected content. The FDRM engine is provided by OEMs.

The FDRM APIs defined by Microsoft are generic. Any FDRM engine can use these APIs to provide the FDRM lockbox and rights management function on Windows Mobile.

Windows Mobile devices without FDRM protection can still use these APIs. The Windows Mobile API described in the FDRM API Reference is a stub that calls into the FDRM provider's API implementation layer if the implementation is present on the device. If there is no FDRM provider, the stub provider operates as if all content has all available rights.

Using OMA DRM V1.0

The FDRM API enables OEMs to plug in the FDRM engine of their choice, for example Open Mobile Alliance Digital Rights Management V1.0 (OMA DRM V1.0). The FDRM API can be used as a wrapper for the FDRM engine, wrapping any FDRM solution in a form that enables applications to access protected content without changes, enabling the use of any FDRM scheme.

Note

For the most recent version of the OMA DRM V1 Standard, go to the Open Mobile Alliance Web site.

An FDRM provider is responsible for implementing an FDRM engine to call into the Windows Mobile FDRM API layer. An FDRM implementation contains components such as a file system filter, a received content handler, and an API implementation layer.

Applications can become FDRM-enabled by calling the generic FDRM APIs. Applications can support any file-based DRM engine by using the Windows Mobile plug-in FDRM model. This model enables you to call one set of generic FDRM APIs for all implementations.

Using OMA DRM V2.0

The Open Mobile Alliance (OMA) revised its specification for Digital Rights Management (DRM) to version 2.0 (from version 1.0) in March 2006. This revision includes changes to the format used for forwardable DRM content.

Content that conforms to v1.0 has a MIME type of “application/vnd.oma.drm.content”, with an extension of ".dcf". Version 2.0 has a MIME type of “application/vnd.oma.drm.content” and extension of .odf.

This means that your device should use the correct extension based on the version while forwarding DRM content files. In order to do this, the API has been extended to include FileDrmCreateForwardableContentEx. Implementation details can be found in the documentation for this function.

In This Section

  • FDRM Registry Settings
    Describes the registry key settings that are used to customize the FDRM engine, user interface (UI), and settings.
  • FDRM API Reference
    Provides descriptions of File Based Digital Rights Managed (FDRM) programming elements for Windows Mobile.

See Also

Other Resources

Digital Rights Management for Windows Mobile Devices