Re: router firwalls?

From: CZ (
Date: 04/08/04

Date: Thu, 08 Apr 2004 04:38:17 GMT

>> Nope. A router only does NAT (network address translation). Some people
classify NAT as a firewall, but it's not in my opinion. It's simply how a
router routes packets from external IP's (internet) to internal IP's (LAN).


Router and NAT are two different concepts.
Router: does routing between two subnets via DA (destination address) and a
route table (OSI layer 3 only).
NAT as we use it: does one-to-many address translation via matching to a
port table (OSI layers 3 & 4).

And a stateless firewall: does packet filtering via packet header values
(OSI layers 3 & 4).

The problem is liberal usage of the word "router".

My Netgear RT314 "router" provides the functionality of all of the
Inbound and outbound stateless firewall rules on both interfaces

Note that I have used the RT314 with NAT disabled and it works as a basic
router, it allows communication between two subnets.