The victimisation of the ordinary netizens by the unauthorised users called hackers have been increased exponentially. These hackers break into your computer and misuse your information for spamming (read 7 ways to avoid being hacked). There are a lot of tools in the market that have been introduced to reduce the threat of cyber security. One of these tools is the NAT Firewall. The NAT Firewall is used to add extra layer of security to your internet network.
What is a Firewall?
In computer networking, the term firewall refers to a system of network security that monitors and controls the data flow which is going out and coming in, based on the predefined security criteria. The internet data is in the form of packets of information that is sniffed thoroughly by the firewall to make sure there is no malicious stuff coming from the external source. The firewall can be hardware or software and even the combination of both. It works as a barrier between a trusted internal network and an external network and provides a secure connection.
What is a NAT Firewall?
The term NAT stands for Network Address Translation. It is used to translate the IP addresses of a lot of devices connected to a local area network to a single IP address. This IP address is usually employed by the router that is being used to connect the device to the internet. This makes the other external devices that intend to access the computers in local network, see the single IP address of the router, hiding all the devices IP addresses from the external threats (). However, the router can be configured as a firewall which will shield the network and will allow only the authorised device to access the computers on the local network. This can add an extra level of security to your internet network that will block any unauthorised attempt of accessing your internet network.
How a NAT Firewall Works?
After allowing the authorised system to access any device in the local area network, the NAT then translate the IP address of the router to a particular computer address. This address is predefined in the NAT table that defines the internal IP addresses of all the devices connected to the local network. This table also describes the world wide web address viewed by the devices outside the network. Although every device connected to the local network has its IP address, the external sources can only see the IP address of the router when connecting to any of the devices in the local network. In short, The NAT firewall works as a middleman between a group of computers connected to a local network and the internet or the world wide web. The NAT firewall blocks all the unauthorised systems trying to access the local area network by the rules predefined in the NAT table. This can be easily explained for a non-technical person by giving an example of three devices named as 1, 2 and 3. All the three devices are connected to one local network. If device 1 wants to call device 4 which is outside the network, the call will first go through a gateway. This gateway will then intercept the call, replacing the IP address of device 1 with IP address of the gateway and makes the call on its behalf. Thus, the device 4 would think that the call is from the gateway and the identity of the actual caller (device 1) would be kept in secrecy, and it does not matter for device 4. Now, the device 4 replies the call to the gateway, and the gateway forwards the response to the device 1, being unaware of the switches made on the way. The gateway is the NAT firewall that works as an agent between an internal device 1 in the local network and the device 4 outside the network or the internet. When you attempt to access any website you need to have an internet connection network. The NAT Firewall of this network translates the IP address of your device to its own and sends your request to the server of the website (that can see the IP address of the router only). However, the NAT Firewall can deny the request if the website is found to have malicious stuff.
Importance of NAT Firewall
As previously discussed that the NAT firewall adds an extra level of security to the Internet network (read more about internet security and privacy in our ultimate privacy guide). It scans all the access requests coming to any device from outside the network. If these requests are legitimate, then the NAT firewall allows the system to access the device inside the network. This will protect all the devices inside the network from being affected by the malicious stuff or from being hacked and misused.
VPNs With NAT Firewall
Using VPN with NAT Firewall will more likely diminish the effect of NAT Firewall. It is because NAT firewall scans the data packets and then allows it to access any device on the network. But these packets become unreadable when using a VPN because it encrypts all the data traffic (know more about best encrypted VPN). However, there are some VPNs available in the market which are compatible with NAT Firewall and do not make the NAT firewall ineffective.
Conclusion – What is a NAT Firewall?
In a nutshell, NAT firewall is designed to provide a subsidiary level of security to a local internet network connection. It plays a vital role in reducing the risk of being hacked and misused. It shields the computers from all the malicious stuff send by the external sources. Thus, if you want to feel safer over the internet, you are highly recommended to use NAT firewall and save your device from the external threats of hacking and identity theft (get the most secure VPN services for high-end internet security and privacy). The cyber security challenge has fueled up the development of these network security systems. People around the world are now looking for the necessary security measures to feel safe over the internet and preserve their online privacy. Thus, NAT firewall is an essential tool to add an extra level of security to your computer network.