Untangle bundles common open-source applications for blocking spam, spyware, viruses, adware and unwanted content on the network in one single Linux distribution. It can be integrated into existing networks either as a router or as a transparent bridge (directly behind the router, but before the switch that connects the client PCs with the router). The best thing about Untangle is that you do not have to reconfigure the client PCs - Untangle works out of the box.

This tutorial will guide you through installation and configuration of Lintrack, a GNU/Linux distribution specialized in networking tasks. We will give two LANs access to the internet along with DHCP and DNS cache servers, and then we will connect our networks using OpenVPN in bridging mode. You should be running all these in well under an hour, thanks to the unified configuration interface of Lintrack.

This how-to explains the process of setting up a FreeBSD system that will act as a wireless router (as well as a wired router) that takes advantage of the ported version of OpenBSD's PF packet filter.

This document describes how to attach modems to a Linux box and allow it to receive calls to connect users to the network. It is like being your own ISP (Internet Service Provider). If your Linux box is connected to the Internet, then the users will also be connected to the Internet. Your Linux box becomes a router. This is also known as RAS (Remote Access Services) in the Microsoft world. In the Linux world it is called PPP (Point to Point Protocol).

This tutorial shows how to set up network-address-translation (NAT) on a Linux system with iptables rules so that the system can act as a gateway and provide internet access to multiple hosts on a local network using a single public IP address. This is achieved by rewriting the source and/or destination addresses of IP packets as they pass through the NAT system.