seful Traffic Accounting Dragon is a traffic accounter that actually gives useful information about traffic instead of stupidly counting incoming/outgoing packets.
Dragon accounts traffic by user, program and timestamp and puts this information into useful correlation.
Dragon is implemented as a Perl script for the backend, using /etc/passwd to automatically get information about user accounts, /proc/net/ to get information about open connections and /proc/ to get information about running processes and which processes currently use which network connection.
All this information can be combined so you can actually see what user caused which traffic using what program and when it happened.
All this information is acquired automatically so the minimal configuration necessary is to tell dragon where it can find its MySQL database.