You may have heard of something called an IP address – if you haven’t, start by reading our article explaining this concept – but for this NAT (Network Address Translation) article, you need to know that IP addresses are limited. You also cannot have two devices on the network with the same IP address
The problem is that different networks, such as your home network and computers on the Internet in general, will inevitably have the same IP addresses or are incompatible in setting their network addresses. NAT solved both the problem of lack of IP addresses and incompatible networks that needed to communicate with each other.
In most cases this is not something you need to worry about, but sometimes Internet problems are the result of NAT not working properly. Therefore, a basic understanding of what NAT is and how it works can help solve the problem.
Where does NAT occur?
In the case of regular users like us, NAT is the job of your router. The router has an IP address assigned by your service provider. This is the address that the entire Internet sees. Each device on your home network is assigned a private IP address that they will use to communicate with each other.
When a device on your network wants to communicate with the outside world, a router replaces it. The router has a public IP address that everyone can see. It keeps track of which private IP addresses were requesting which traffic and ensures that data packets are routed to the correct device.
Private IP addresses versus Public IP addresses
Before we get into the types of NATs you will encounter, it is a good idea to have a quick discussion of private and public IP addresses.
By convention, certain ranges of IP addresses are reserved for specific purposes. Public IP addresses are reserved for devices with Internet access, such as a router or web servers Your ISP gives your router a public IP address that everyone on the Internet can see. Usually a private internet address looks something like 192.168.0.X or 10.1.1.X, but this depends on the router to the other. While private addresses must be unique on a private network, they are almost certainly the same on private networks.
As mentioned above, the public IP address is the one that everyone on the Internet sees. When you visit a website, your browser connects to its public IP address. Typically, home routers do not allow direct access through their public IP address, which was not initiated by them. This means that you can’t just enter your friend’s public router address and access devices on their network.
However, some web services and devices, such as game consoles, require a more lenient approach. This is where different types of NAT come into play. Often times, problems arise because the NAT type of your connection does not match the type of service you are trying to use. Next, we’ll look at NAT types in more detail.
While the basic idea of ??what NAT is is not overly complicated, in practice there are many nuances of how it works. There are different types of NATs that suit different translation needs.
Static NAT style maps one specific private IP address to a specific public IP address. With static NAT, you can directly access a device connected to a public address.
This is a type of NAT used for web servers that are also part of a private network. When accessing the server through this static card, you also cannot access other devices on its private network. However, the server itself can communicate seamlessly with devices on its private network.
Dynamic NAT is used when you have a pool of public IP addresses that you want to dynamically assign to devices on your private network.
It is not used to access the web server from outside. Instead, when a device on the private network wants to access the Internet or other resource not on the private network, it is assigned one of the public IP addresses in the pool.
NAT Overload (PAT)
With static and dynamic NAT elements, NAT overloading style is the most common form and is used by most home routers. It is known as NAT with port address translation (PAT) among other names.
In most cases, your router is assigned one public IP address, but all devices on your network probably want to be able to access the Internet. Using NAT overload, a router establishes a connection between its public IP address and the server’s IP address. It then sends packets to the server, but also assigns a destination port to return.
This helps it to know which packets are for which IP address on your private network. By the way, this is part of the PAT process.
Proprietary NAT Types
To further confuse the situation, some companies have decided to apply their own NAT classifications. This is mostly applicable to game consoles and you will find that when you test your network, you will see that you are using something like NAT Type 2 or NAT Type D.
These classifications are specific to console or device manufacturers and you should check their official documentation to understand what each classification actually means.
Common fixes to NAT issues
In most cases, NAT works perfectly and with complete transparency. However, sometimes it fails or interferes.
Again, game consoles are more likely to run into problems because some of their services require your network to accept requests to access the public IP address from the outside, since standard NAT configurations usually don’t allow this. The good news is that there are a few common fixes you can try to make NAT less harsh and allow incoming connections.
First, log into your router (according to its manual) and check if UPnP (Universal Plug and Play) is enabled. This feature allows applications on your local network to automatically forward ports without having to mess with network settings. Just keep in mind that any malicious software on your network, such as malware, can also use UPnP. If you are using this feature, make sure all of your devices are scanned and cleaned.
You also have the option to manually perform port forwarding so that devices that require a less stringent connection can receive it on a case-by-case basis.
It’s only natural
That’s all you need to know about what NAT is to get started. The real fundamentals of NAT can quickly get complicated, but if you understand what NAT is doing at a high level and why sometimes things go wrong, you can also understand why certain fixes work or don’t work at startup. into network problems.