What is it ?

A small shell script designed to run on linux powered routers (OpenWRT, DD-WRT, Tomato, and other routers where shell access is available). It provides per user bandwidth monitoring capabilities and generates usage reports.

How do I use it ?

Please have a look at this wiki page : http://code.google.com/p/wrtbwmon/wiki/Deploying

Alternatives

wrtbwmon is not actively developed anymore. I invite you to consider these alternative projects :

1. The tomatousb guys have done an awesome job at integrating its functionality into the tomato firmware and have taken it way beyond anything I could have dreamed of. Look for the IP traffic monitoring features in Toastman or Teaman latest builds !
2. Gargoyle router also has a quota management system.