On Wed, 2 May 2001, Adam Bower wrote:
MRTG will let you know how much bandwidth is being used but can be a real pig to setup and you will have to configure SNMP on the customers box (or your router (yes I know the upstream won't give the stats)) anyway take a look at http://ee-staff.ethz.ch/~oetiker/webtools/mrtg/mrtg.html
might help if i put you in the root of the doc tree! http://ee-staff.ethz.ch/~oetiker/webtools/mrtg/
also on the same site is RRDtool which I have heard good things about http://ee-staff.ethz.ch/~oetiker/webtools/rrdtool/
Adam