Wireless streaming
Applies To: Windows Server 2008, Windows Server 2008 R2
Wireless streaming scenarios apply primarily to three kinds of devices that are capable of rendering streaming media content: portable computers, personal digital assistants, and Internet-capable mobile devices. If your target audience includes these devices, consider the following:
Enable forward error correction (FEC) on your publishing points. Forward error correction is a common method of preserving the integrity of data transmitted over unreliable or slow network connections. When forward error correction is used, the server broadcasts extra packets on the assumption that some of the packets will be lost before they reach the client. This process enables the client to reconstruct the original transmission even if a significant portion of the packets are missing.
Portable digital assistants (PDAs) typically have a much smaller viewing area than desktop computers or even portable computers. When encoding video for a PDA, you must accommodate not only the PDA's small screen size, but also its modest computing power. For example, the screen size of a Pocket PC is 320 pixels by 240 pixels, but the best compromise of picture quality, frame rate, and bit rate suggests a frame size of 208 pixels by 160 pixels and a frame rate of 20 frames per second. To render streaming video at full screen size, the frame rate must be reduced, which often makes movement on the screen excessively jerky.
Cellular data transfer technology has not advanced to the point of permitting broadband access to streaming media. Devices that use Cellular Digital Packet Data (CDPD) or other cellular modem technology are generally restricted to a bit rate of 9.6 kilobits per second (Kbps) or less. Bit rates in this range cannot support streaming video.