Microsoft KB Archive/836545

= FIX: Some content may cause rebuffering on certain networks =

Article ID: 836545

Article Last Modified on 8/4/2004

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APPLIES TO


 * Windows Media Format 9 Series Software Development Kit

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SYMPTOMS
When streaming some content from a Windows Media Services server, client computers may experience buffering. Network administrators may notice dropped packets at various router hops or switch hops.



CAUSE
This problem occurs because some network hardware may have buffers that can be exceeded by large frames (such as key frames) that have higher bit rate content. The content is served from the server based on the Send Time of the packet as specified in the file itself. When the large frames in the content are all sent at the same time, the buffer limit may be exceeded on the network hardware. This overflow may cause playback problems on the client.



RESOLUTION
The following file is available for download from the Microsoft Download Center:

Download the WindowsMedia9-KB836545-ENU.exe package now.

For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to Obtain Microsoft Support Files from Online Services

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file.

The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.   Date         Time   Version            Size    File name --  12-Feb-2004  13:34  9.0.0.3125      2,071,288  Wmvcore.dll



STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section of this article.



MORE INFORMATION
After you install the hotfix, you have to encode the content again. You can either do this by means of one of the following:
 * Microsoft Windows Media Encoder 9 Series
 * The WMVCopy tool that is available in the Microsoft Windows Media 9 Series Format SDK

If you maintain the same profile when you encode the content again, you can expect no loss of quality because the content is not decompressed or recompressed. Instead, the packets of the content are modified to resolve the problem.

Additional query words: WMS &quot;send time&quot; &quot;key frame&quot; &quot;packet size&quot;

Keywords: kbdownload kbfix KB836545

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