How To: Make a lag switch

I have a little brother who's a dick and who can't tell 10mb internet bandwith from his dick. Actually he can only tell when things are "working" or "broken". He basically downloads on steam and torrent constantly leaving no uplinck, cutting me off completely from online gaming. Of course since he doesn't know what speed he's dowloading at (or want to know), he couldn't tell if his intenet connection is slower than before. So I want to know if the orange cable bieng split will cut internet off completely or just slow it to a crawl. In witch case I can jack the cable comming from the switch. Many thanks in advance.