„i.NET - QoS and security for Linux” is a open source project that provide easily configurable firewall and traffic management. It based on Linux operating system with specially prepared kernel, iproute2, iptables and bash scripts to configure specific rules.
Documentation is availble at http://wiki.inet.one.pl/i.net_scripts
Support forum: http://forum.inet.one.pl/
Fully featured commercial scripts are also availble through: http://www.inet.one.pl/