Fair bandwidth distribution of an internet connection shared with IP masquerading

Hi everybody !
I set up a Linux box (Fedora Core 4 on a Pentium III 833MHz processor
and 128MB RAM) to share a broadband connection (dialup type : uses
rp-pppoe) over a local Ethernet LAN. The material available on the net
was of great help.
The sharing worked flawlessly but then I ran into the next problem
which the tutorials had not foreseen :
Fair bandwidth distribution.

Can anyone point me to any material on the internet or to any reading
material which broaches on the subject of imposing bandwidth
restriction using possibly iptables.
Any other solution would be equally welcome as long as it does not call
for using a proxy.

Thanks in advance.

--- Anirban

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