Hi,
I have a usb 2.0 hub with 4 ports, I've to connect 2 usb cameras and a arduino board for a projects and my question is how to control the bandwidth of each port on the usb hub programmatically or some other way and how to assign com port number to usb hub ports?

Kindly help me out!

What is the end goal here?

The operating system usually controls all this. You probably, even best case, won't get full bandwidth for transferring files regardless. You can do it, but I don't think the amount of effort required to do this will equal the possible gains you might see.