One person on my network does a massive download, not caring too much about how long it takes. Someone else on my network doesn't want his incessant video streaming interrupted. My understanding is that this is solved using QoS, to prioritize streaming packets over update downloads, or packets from one source over another source.
However, I think the link that gets congested here is the one between me and my ISP. I am guessing that if QoS was configured on my end, packets would still be sent indiscriminately to my router, they would still de-bottleneck even though my router is prioritizing them, and there would be no difference in performance. (I attempted to include a diagram to explain this but apparently I don't have enough reputation.)
If I wanted the streamer's stuff to be prioritized, would that have to be set up on the ISP's end or is there anything I can do on my own network?
I apologize for my noobishness.