Experiencing network problems? The problem could be down to your PC's Network Address Translation (NAT) throwing an error. NAT errors can spoil your surfing and gameplay experience considerably, but not everyone knows what a NAT is, and how errors can ruin your fun.
If you don't know what NAT is, we'll help you understand its meaning and how you can fix "double NAT" errors.
What Is NAT, and What Causes a Double NAT Error?
NAT is a translation method. It translates the public IP address that your Internet Service Provider (ISP) provides to a private IP address used by your local network.
The middleman in this equation is the router, which performs this translation. However, when you're using two routers or connecting your router to an ISP gateway, the translation can go wrong and lead to double NAT errors.
Double NAT errors occur when your router is connected to another router or gateway. Since the IP address is translated twice in such setups, your network is essentially split into two different private networks. Both devices will have problems communicating with each other because of two different sets of IP addresses and firewalls.
Double NAT can cause network problems and interfere with online gaming, VPN connections, port forwarding, and port triggering. Double NAT often renders Quality-of-Service (QoS) configurations useless. It can also interfere with smart home devices like cameras and doorbells.
Essentially, double NAT can choke your network and stand in the way of effectively using many devices. Let's talk about how to fix it.
How to Detect Double NAT on Windows
If you suspect something is wrong with your router configuration, you need to see if double NAT is currently occurring. Fortunately, you can do that from your Windows PC with a few quick steps.
To check if double NAT is the problem:
- Launch an elevated Command Prompt by pressing Win + R, typing cmd, and pressing Ctrl + Shift + Enter.
- Execute the following command:
tracert 8.8.8.8
- You'll see a list of hops. If the first two hops are private IP addresses, you have a double NAT issue.
If you're unsure as to which IP addresses are private or public, private IP addresses are typically in specific ranges, such as:
- 192.168.0.0 to 192.168.255.255
- 172.16.0.0 to 172.31.255.255
- 10.0.0.0 to 10.255.255.255
If you see IP addresses that look very different from these, those are public IP addresses. In our case, for example, only the first hop shows a private IP address while the subsequent hops show public IPs. This indicates that our network doesn't have a double NAT problem.
How to Fix Double NAT Errors
Here are some ways to fix double NAT errors:
Remove a Router
You guessed it. If your current network setup includes two routers, the easiest solution is to remove one of the two routers from the equation. If you don't absolutely need those two routers (most regular users don't), just use a single router provided by the ISP.
Use One Router as a Modem
If you do need to use two routers, you'll need to use your ISP's router as a modem. This involves plugging the ISP's router into the second router's WAN port.
Use Bridge Mode
Another method to fix double NAT errors is enabling bridge mode. Some routers don't have this option so you'll first need to check if yours does by accessing the router's firmware.
The bridge mode turns a router into a modem that relays all the traffic that comes its way directly to the router.
When you enable bridge mode, it disables NAT and allows all traffic to pass through without translation.
The method for configuring bridge mode differs for every router. You can generally access the router firmware by typing 192.168.0.1 or 192.168.1.1 into the browser's URL bar and pressing Enter. Log in using the credentials provided by the ISP or the manufacturer.
If you can't find the bridge mode settings, it's best to contact the ISP or manufacturer.
Forward Connections Using DMZ
If bridge mode isn't available, you can put your router in the demilitarized zone (DMZ). When you set up DMZ, you'll create an area where all ports are forwarded to. This way, you won't be disabling NAT, but you'll create a port forwarding rule that says all traffic, from any port, is forwarded to a specific address.
Effectively, DMZ is a setting that bypasses DHCP, NAT, and firewall to give another router a direct connection to the internet.
Again, your router may or may not have the DMZ option.
Before you set up DMZ, you'll need your secondary router's IP address. This should be a static IP address, which means you can't use DHCP mode. Once you've configured the router to use a static IP, go to the router firmware's homepage or the page showing basic network details and note down the IP address.
To set up DMZ, log into the router's firmware and locate the DMZ setting. Enable DMZ and enter the other router's static IP address.
Eliminate Double NAT Errors and Enjoy Your Network Again
Double NAT errors be a major problem, especially for those who love online gaming. Solving the double NAT error can be as simple as removing the second router or involve some technical steps like using a static IP address and enabling DMZ.
Hopefully, you were able to resolve the double NAT issue with one of these errors. While double NAT can prevent you from joining sessions, there are other factors that can cause the game to lag even though you're able to join the session. Of course, there are methods to fix everything when you're a determined gamer.
