Is there a way to check where a firewall and NAT are running on a network?
For example I can find out my gateway, DHCP, NDS, WINS server by checking network connection details. I would like to know if there is a Firewall or NAT running between me and the internet also.
would traceroute/tracert show the IP address of any Firewalls and NATs on my network?
from a command prompt, type ipconfig /all (assuming windows). If your ip address looks like 10.something.something.something, or 172.25.something.something, or 192.168.something.something, then your are on a NAT network. Those IP addresses are non-routable and reserved for internal NAT networks.
You can get a simple map of your network using tracert, which shows you the number of hops from your machine to your destination. If you do something like "tracert google.com", and see more than a couple of hops, then you can sort of tell where your network ends and external networks begin. Everything on your network will share the first few octets of your IP address, and if you have a firewall and a router you will see them as hops in the output. From there, you could do additional probing to determine other things about the machines by using something like nmap or similar.
Of course there is. I know of very few networks that use routable ip addresses internally and therefore don't use NAT. Here's how you can tell:
Run ipconfig or ifconfig on your computer and make note of the ip address. Then browse to a site like www.ipchicken.com and make note of the ip address. Compare the two. If they're different than your computer is behind a NAT device.
