Hi Shiv In addition what we also have is a server variable. If you want to change the throttling rate programmatically you could use server variables ( details - refer section "Throttling with Server Variables"). Also Scott Hanselman blogged about how to do this here . And as Jack mentioned...

All of the documentation on the bitrate throttling model uses the term MIME type. But in fact the module only responds when a url has a certain file extension (*.wmv, *.mov etc.) This design foraces us to have to implement our own handlers/module and the logic for throttling is media files are issued...

This could be a bit complicated to explain and understand so I'll try my best to explain the set up. Our media files (videos) are Flash video (.flv) files. These files are not directly accessible as a url that end with a .flv. As a result the bit rate throttling module does not intercept requests...