PC Problems? I am a PC TECH.

[Kakariko]

I have an internet router, with 3 users plugged into it (including myself). Another user is almost constantly downloading, making things slower for everyone else. Also, I'm from Australia, where every ISP has download limits. I was wondering if there was a way to slow the speeds down through just one port of the router and if it's possible to have internet stop working on one port, once that user reaches a set download limit per day.

Whether this can be done or not, I'd like to say thanks all the same