Performing DRM Individualization

Individualization is the process of updating the DRM component on the client computer, encrypting it, and making it unique. When a computer is individualized, the DRM component is tied to the computer and will not be able to decode content on any other computer. The Windows Media DRM Client Extended APIs provide support for individualizing the DRM component on client computers.

Individualization is performed by calling the IWMDRMSecurity::PerformSecurityUpdate method. You can call PerformSecurityUpdate so that it will individualize only if the version on the server is newer than the one installed on the client computer, or you can force individualization without regard to the relative security versions. The flag for as-needed individualization is WMDRM_SECURITY_PERFORM_INDIV. The flag for forced individualization is WMDRM_SECURITY_PERFORM_FORCE_INDIV.

PerformSecurityUpdate is an asynchronous call. It will return quickly and then generate events to provide status information about the individualization process. The majority of the events generated will be MEWMDRMIndividualizationProgress events, and each has an associated IWMDRMIndividualizationStatus interface. To get the status interface, you must call IMFMediaEvent::GetValue to retrieve an IUnknown pointer that is on the same object and then query it for IWMDRMIndividualizationStatus.

You can get data for a WM_INDIVIDUALIZE_STATUS structure by calling IWMDRMIndividualizeStatus::GetStatus. Each event that is generated has its own object with status, so you must go through the process of getting the event value and querying for the status interface every time.

Depending on the size of the download, there may be dozens or hundreds of MEWMDRMIndividualizationProgress events. When the individualization process is finished, an MEWMDRMIndividualizationCompleted event is generated.

When individualization is completed, the only existing objects that will reflect the new individualized state are those that inherit from IWMDRMSecurity. All other existing objects will not be updated. You must release and re-create any other objects so that they will reflect the new individualized state.

DRM Individualization Example

Programming Guide

Using the Media Foundation Event Model

Windows Media DRM Individualization Best Practices