How to forward an URB from Window USB Driver to another PC?

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Windows

driver

In my course, i need to develop a USB sniffer capture URB (USB Request Block) pass from USB device, then forward to a another PC.

For example, look at "Setting -> USB -> Enable USB Controller" in VirtualBox. When you enable this setting and plug an USB device in Host PC (Window OS), you can attach this USB device into Guest PC and read/write data or do something else in the USB device. Simultaneously, on Host PC, you can't see the USB device. If you can also detach this USB device from Guest PC, on Host PC, you can see the USB device again. URB of the USB seem to be forwarded to VirtualBox USB Driver.

I don't know what mechanism that they used? Could you please explain for me?

P/S: Can i develop a filter driver to do that?

Thank so much!