NAT is what your router does to protect you and your pc/pc's from the outside world. It also has to do this because your service provider gives you one IP address for your residence. So if you want to have more than one pc, or do wifi then you need the router.

Think of the router as a guard station managing traffic in and out of your house. You generally are able to go out without being hassled by the guard. But when you want to come back in, they have to check your credentials. Everyone in the house has the same name at the point of entry. The guard just knows everyone by the name Kimock. This is akin to the one public IP address your service provider gives you.

So in order for the guard to keep things straight he has to rename people so they aren't all called Kimock. The network address translation is the way he does it.

You have a public IP address that's say:

67.173.142.84

And you have 3 pc's hooked up to the router. The router uses a range of reserved IP address to communicate with the in-house pc's.

Those are:

192.168.1.100

192.168.1.101

192.168.1.102

Say your torrent computer is 192.168.1.101

That's the address the router gave it when it booted up. The last 3 numbers of that string are really the only important ones for basic understanding.

So your computer boots up, the router sees it and says, oh, there's a computer booting, he needs an IP address I'll give him .101 this time. Then when you start running bit torrents there is a lot of data going in and out of the computer and out to the world.

The router knows that pc inside the network as #101, then as the data goes out, he keeps track of what #101 sent him, converts .101 to the 67.173.142.84 public IP address. Then when stuff comes back in for #101 he knows that he needs to convert back from public IP to .101 and sends the data to that computer. So there is a constant translation going on inside the router/guard house. Ah, this batch of stuff from .101 needs to go out so I convert to public address and send. Then ah, this batch of stuff is coming back in for .101, I need to convert public IP to in-house and send to .101

So that's where the network address translation term comes from.

Bit torrent, and other internet type programs (browser for ex) all work on a port system. It's the way the different software communicate with each other in your pc and with the outside world. You can think of them like a usb port or a hdmi or vga port on your pc. Same concept, get things in and out. But they are just software ports, there is no physical piece to it like the other stuff. There are 65,535 software ports.

Your bit torrent program uses one of them to send and receive stuff. Many are reserved for standard internet functions like browser uses port 80, email ports 110 and 25 generally. FTP on port 21 etc. So bit torrent uses higher number that aren't commonly used for other things. So your torrent program might be using 50581.

Your torrent program and pc are using that port to communicate with the router and with the outside world.

You need to tell your software firewall (windows firewall or the one in your antivirus suite) about this port and you need to tell your router about this port.

When you install the bit torrent program it usually asks if it's okay to make a rule in the software firewall to allow data traffic in and out on that port. That's great, but you still need to alert the antivirus program and your router that they should allow all data traffic on that port in and out of your machine. #101.

The router is stupid and only does what it's told. So you have to tell it to allow this traffic. You have to log into your router via a browser interface and then go to the applications and gaming area, or the port forwarding area.

Create a rule, (it's easy, you'll see once your there) that says for computer .101 let all traffic pass on port 50581.

It's really as easy as keying in the .101 and the 50581 in the right boxes and clicking save changes in the router configuration utility.

Now the only whammy that happens is that your router might give .101 to another computer and then the rule won't work right.

Remember, you have 3 pc's and if you shut your torrent pc down, .101 address gets released and free'd up in the router. So another pc boots and the router says, oh, okay, you need an in-house address, I'll give you .101 as it's free right now.

Then you come along later, turn on the torrent computer and the router says, oh, another pc needs an in-house address, I'll give you .102 which is free right now.

You created the torrent rule to point to .101 and now another computer has that address. So you'll show up as NAT. Ports not forwarded correctly. The rule applies only to the computer with the .101 address and you don't have that now.

So the way around this is to go back into the router, or just do it while you were in there in the first place creating the port rule.

It's called a client reservation or dhcp reservation. You tell the router to reserve .101 only for my torrent computer.

DHCP is just the acronym for the little module that handles giving out the in-house IP addresses in the router. Dynamic Host Configuration Protocol for the curious. :-)

Almost all routers now have a quick and easy way on the general or setup tab of the router configuration utility to set up a dhcp reservation.

You probably know your pc's by name, mylaptop, mydesktop, kid'spc, wifey's pc etc.

The router knows your computer by what's called a MAC address. Media Access Control for the curious. :-) The MAC address is a hard-coded, burned into the adapter card at the factory, unique in all the universe, hexadecimal address. Don't worry about any of that, as you will likely be able to click on a dhcp reservation button, then see a table and check the box next to "mylaptop" and do the reservation.

You actually want to do this first. So make the reservation, and note what the last 3 digits are for the IP address you have at that moment. It might be .100 or .101 or .102 or 110.

Then use that number to create the torrent rule in the port forwarding area.

If you are showing as NAT here it would be great to get that fixed. However they discern your port forwarding issues here isn't 100% foolproof though. So just because you are showing as NAT here doesn't mean that you for sure are, or that you can't download and seed successfully. You'll have to kinda look at your torrents and see. If you're not uploading much and not connecting to people to upload then it's likely you need to fix the port issue.

Good luck,

goother