Monitor NAT client bandwidth and Data

[shaumux]

Hi i am looking for something which can monitor and report the data and bandwidth usage for nat clients with dynamic ips.
It need not report in realtime.
Manually configuring iptables reporting for each client is not possible because of the size of the network.

Does anybody have any knowledge of any such software?

Thanks

[i0]

http://phptrafmon.sourceforge.net/en/index.php

I'm using it in some of my routers.

If users are dynamic you'll need something that will also identify them (by MAC address maybe).