SmoothWall Express is a network firewall, designed with home and small business users in mind. It is based upon a security-hardened subset of the GNU/Linux operating system and is completely free to use, download, and distribute. SmoothWall Express offers facilities and features normally only seen in expensive commercial offerings.
Devil-Linux is a special secure Linux distribution which is used for firewalls, routers, gateways, and servers. The goal of Devil-Linux is to have a small, customizable, and secure Linux system. Configuration is saved on a floppy disk or USB stick, and it has several optional packages. Devil-Linux boots from CD, but can be stored on CF cards or USB sticks.
Local Area Security Knoppix is a 'Live CD' distribution based on Knoppix but with a strong emphasis on security tools and small footprint. There are two different versions of L.A.S. Linux to fit two specific size requirements. There is a 185 MB version and a 210 MB version to fit on MiniCDs of the same size.
The Public IP ZoneCD has been created to help implement safe, free, wifi hotspots. NoCat dynamic firewall rules are used for user access and authentication. A transparent proxy sends all "Public" requests from NoCat through a content filter (Dansguardian) to block porn, hacker sites, extreme violence, illegal drugs, and other obscene and explicit Web sites. The content filter also blocks files extensions to protect your network from viruses, and restricts file sizes to save bandwidth.
redWall is a bootable CD-ROM firewall which focuses on Web-based reporting of the firewall's status. It includes Snort, snortsam, dansguardian, and support for fwbuilder, squidguard, reporting (using BASE/sarg/ntop/webfwlog), VPN (Openswan/PoPToP/Openvpn), Spam Filtering (spamassassin, dcc, razor2, clamav, amavis-new, dspam and maia mailguard), and mail-based, alerting. Configuration data are stored on a floppy or USB disk.
Tunix is a set of tools used to generate small bootable Linux images. It can be used to learn how to roll your own distribution, or to port embedded systems. The basic release uses busybox and has a kernel with netfilter-enabled modules. A uclibc iptables binary is included, so you can roll your small firewall from a floppy.
The Auditor security collection is a live-system based on KNOPPIX. It provides tools for analyzing the security of a system. It features a menu structure that reflects the stages of a security check: foot-printing, analysis, scanning, wireless, brute-forcing, cracking. In addition to about 300 security tools, the collection includes background information regarding standard configuration and passwords, truly extensive word lists, and more mundane productivity tools.