How to limit bandwidth and speed of shared internet over hotspot?

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Hi, everybody! This is my first question on ask.fedoraproject.org . Here we go:

I have internet through USB 3G modem. I turn on hotspot through wi-fi settings in Gnome Network Manager. And everybody who has password can access internet with no limit.

I want to limit bandwidth and, if it possible, speed for all clients. How to do this?