Hi there is quite some data on Traffic shaping here (search for CBQ, HTB or QoS) The problem with the rpm is that you can only limit the traffic for all of your clients or none. (At least out-going traffic) If you want per ip traffice shaping the best thing to use is HTB-init, but to make that work you have to use SME 7.0a or recompile your kernel. So that leaves CBQ. The problem with that is that it uses a form of static-shaping, the up- and download speeds of a class (in with you can put an ip) are set, and if you put multiple ip's in a class it is hard to get a fair share of the bandwidth when one is downloading and one is playing a game and generating not so much data.
So if you want per ip bandwidth-management the easiest way is to wait for SME7.0 and use some form of social-bandwidth-management. ( 'If you don't stop downloading now, I wil kick your *%&! '

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