Duration of accelerated streaming for the network source, in milliseconds.

Data typePROPVARIANT type (vt)PROPVARIANT member
DWORD (stored as LONG)VT_I4lVal


The constant MFNETSOURCE_ACCELERATEDSTREAMINGDURATION defines the GUID for this property key. The property identifier (PID) is zero.

Applications can use this property to configure the network source. To set the property, pass an IPropertyStore object to the source resolver. For more information, see Configuring a Media Source.

This property applies to the Fast Start feature of Windows Media Services, which plays content quickly without waiting for lengthy initial buffering. When using Fast Start, the server running Windows Media Services will send some data at the beginning of the content at a faster rate than that specified by the bit rate of the content.

The default value of this property is 10,000 milliseconds.


Minimum supported client

Windows Vista [desktop apps only]

Minimum supported server

Windows Server 2008 [desktop apps only]



See also

Media Foundation Properties
Network Source Features
Networking in Media Foundation