netcount is a command line PPP traffic logging and
statistics display tool for Linux. Logging is done
via a small shell script which is called during
the ip-up, ip-down, and system startup processes
and from cron, while analysis and printing is done
by a program written in Python. Statistics can be
made on a per-call, daily, and/or monthly basis. Also part of the package is nstat, an X utility to display connection status, to hang up, and to start and terminate pppd.