[Wlug] Bandwidth sharing problem

I have a friend with a bandwidth sharing problem. There are two linux boxes (one Debian Sarge, one SuSE 9.3) attached to an old Linksys 10/100 wired router on cable internet (3Mbps confirmed download speed). When the Debian box is downloading a large file, it hogs all the bandwidth, and the SuSE box is very slow on the internet. Is there an easy way to limit download speed on one or both boxes to make them share nicely? I looked through the manual for the router, and I don't see a way to do it there. If there's not an easy way to do it, I'd still like to hear the difficult way to do it. Thanks, Greg