IP Traffic Volume uses Linux kernel iptables to
log incoming and outgoing bytes though your
network device(s) and can dump summarized log
statistics in ASCII to the console or display in
HTML via the included CGI interface for displaying
on a Web server. It is highly configurable as to
what kind of traffic is counted, e.g. to and from
specific ports and/or specific IP addresses or
groups of ports and addresses. It uses a mininum
of resources and doesn't need a database for the
logged data.