Building cheapest gateway machine.

What would you like your gateway machine to have? I consider
most people will want at least following things in a gateway,

1. Firewall
2. DHCP Server
3. Easy administration tools
4. Monitoring Tools

And also there may be less essential things like

1. Caching DNS Server
2. Caching Proxy Server
3. HTTP Server

Most latest router products can give all above things out of the
box. But most of the routers are considerably expensive. Now
what if you have ran out of budget to buy such funky routers?
Well you dot need to worry! You can build a cheapest gateway
machine with cost as less as FREE!

There are plenty of Linux distributions (Open Source and
Commercial) available aimed for this purpose. These distros
provide out of the box services which a gateway or a server
machine might need.

Most of these distributions provide you excellent monitoring and
administration tools. Some have web based administration interface.
There are good bandwidth management tools available. Firewall is
conventional iptables / ipfilter based firewalls and also custom and
open source front-ends for configuring the same.

Major feature about these firewalls is that they also provide you Live
CD distributions. Configuration files can be saved to floppy discs
or also on the USB disks. You can also create your own custom CD
with configuration burnt on it. So, in case if your gateway machine
goes down, pickup this CD put it into other machine and then that
machine can readily start functioning as the gateway. Effective way
to handle fail-over! Most of these distros provide good support for
hardware (As Linux does anyway!) one can run it on any machine like
old Pentium machine to any new high-end machine. But you ideally
don't need a powerful machine. In case of Live CD distos, you don't
even need any hard-drive.

Some of the firewall distros are -
Devil Linux
IP Cop Firewall
Coyote Linux
ClarkConnect Gateway/Server