Limit net bandwidth share in xp network

hello i’ve got this windows xp professional setup on 5 different machines, they are all hubbed by a 10/100mb RJ45 connection to a server (with a cable internet connection which also runs on xp). now this my friends and i we are all having difficulties to share the bandwidth equally. is there any utilities or methods (without having to get more extra hardwares) in xp that solves this problem? thanks for heping!