Vuurmuur is a powerful firewall manager for Linux. Vuurmuur supports IPv4, IPv6, traffic shaping and live monitoring. It has an easy to learn configuration that allows both simple and complex configurations, and can be fully configured through the Ncurses GUI.
okon's bandwidth manager is a simple tool for efficient traffic shaping. It aims to give a fair share of bandwidth to each host while imposing particular rules. Its configuration is straightforward and it is almost maintenance free, as it automatically detects hosts on the network. Obwman
... [More] prioritises traffic of HTTP, TCP ACK, and TCP initiate session. It runs on Linux 2.4/2.6. [Less]