Seeking to a part of video that hasn't been loaded yet (on progressive download)

I was told there is a server technology that allows user to seek to a part of video that has not been loaded yet even if I am using progressive download, no开发者_JAVA百科t true streaming.

What technology is it?

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There are multiple ways to handle what you describe, for example: http://h264.code-shop.com/trac#Timeshiftingseek or http://stream.xmoov.com/.

Obviously this won't be able to play data you didn't receive. It's a standard progressive HTTP download where the video file is "cut" on demand server sided.