Figure 15: Browsing Erica’s shared music library for playback in Windows Media Player

DMP devices are fundamental for advancing the ecosystem of networked devices in the home. However, the new Windows Logo Program (WLP) will not certify devices that implement only the DMP role. We encourage companies to continue building devices with DMP functionality. In addition, we require the inclusion of the DMR role to interoperate with the Windows 7 Play To feature, as described in the preceding scenarios.

The rationale for this decision is simple. Families are storing several thousand pictures, audio files, and video files on PCs and other storage devices on their home networks. Managing this media content for one or more media libraries is an activity that is suited to the information management functions of a computer. Large media databases make it challenging to find items. Windows 7 addresses this problem through integrated search, tagging, and unified metadata across media applications and Windows Explorer. Searching for a song from a particular artist or searching for a family vacation photo is fast compared to browsing a file structure. By including the DMR role in devices, users can take full advantage of Windows capabilities for interacting with and searching media, while playing the content to the selected network media device by using the Windows 7 Play To feature.

Figure 17 shows the protocol layers in a digital media player. DMP devices support Wi-Fi or Ethernet for connectivity. DMP devices implement TCP/IP, UDP/IP, and HTTP. They implement the UPnP Media Server Control Point functionality to browse the media library in any networked DMS. DMR devices implement HTTP and extensions to receive content from a DMS. Some use RTP for transfer.