Secure Audio Path Technology

Microsoft’s Secure Audio Path (SAP) technology provides fewer opportunities to steal digital content than conventional digital rights management (DRM). In general, DRM tools allow content owners to define attributes of a digital audio file, such as how many times it can be played, whether it can be copied to a CD, and whether it can be played on more than one computer or device. This information is contained within the content file, and the actual audio content is encrypted. If a user violates the parameters set by the DRM information—for example, by making a copy of the file—the file cannot be decrypted and will not play.

With regular DRM (left), when a user attempts to play a protected file, the DRM client checks to see if the playback client (Windows Media Player, RealPlayer, etc.) and related components contain an appropriate digital signature, meaning that they understand and honor this particular DRM scheme. If the client sees that the player and related components are signed, it decrypts the program, allowing it to be played.