A bandwidth throttling method is provided. The method includes receiving by a receiver from a QD Vcel cannon, a plurality of multi-frequency light pulses via a plurality of channels. The receiver determines that the plurality of multi-frequency light pulses comprises an out of band (OOB) signal transmitted over a first channel of the plurality of channels. The receiver receives from a first laser device of the QD Vcel cannon, a first light pulse of the plurality of multi-frequency light pulses. The first light pulse includes a first frequency for testing a visibility of the first light pulse at the receiver. The receiver determines if the first light pulse is visible at the receiver.