Firewalls: What is the difference between Policy, NAT and Routes?

Posted by Jakobud on Server Fault See other posts from Server Fault or by Jakobud
Published on 2010-04-05T19:17:36Z Indexed on 2010/04/05 19:23 UTC
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firewall

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fwbuilder

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iptables

I'm learning fwbuilder and firewalls in general. I don't understand the differences between Policy, NAT and Routes. They all seem like they are just ways to tell the data where to go depending on what it is and where its coming from.

What is the real difference? Is a properly configured firewall taking advantage of all three (Policy, NAT and Routes) or are they just three different ways to accomplish the same thing and you only need one of them?

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