BleepingComputer.com: how2 monitor multiple laptops on1 internet connection

hi,
i'm living in a house with 5 people who all have a laptop. we share ONE wireless internet connection which works out pretty good all things considered.

as the owner i'd like to be able to monitor how bandwidth much each person is using, is that possible?
i can see everyone's IP and MAC address in the modem settings but am unsure how to monitor each one.

at the moment i use NETMETER and BWMeter to monitor my own connection. am i able to use any of those programs for my purpose?

i'm in australia and use iPrimus as an ISP and they supplied a iConnect Access modem.
all help is appreciated and thanks in advance