NAT is an acronym for Network Address Translation. This the technology applied in IP addressing within an organization’s internal network.
What is Network Adress Translation (NAT)
This is the process of resolving a public IP address from the internet to a group of Private IP address inside a private network of a company or an institution.
Advantages of Network Adress Translation
Economy and security are the two main advantages of using NAT in networking. It is economical in the sense that a company or an institution will only require 1 public IP address. Besides, each public IP address is paid for.
Secondly, NAT improves security since hackers may not identify which IP addresses are assigned to individual computers inside a private network. Hackers use IP addresses to attack and exploit target computers.
Function of NAT
NAT limit IP address by duplicating IPs within a private network. You may ask why duplication? This is because network researchers invented NAT to prevent exhaustion of IPV4 address. Duplication of IPs was one of the easiest ways to re-use IPv4 address. You may find all IPv4 details here.
How Network Address Translation Works
For example, assume an office with 1000 employees. Assume that each employee uses a laptop, an IP phone, and a desktop workstation during working hours. That translates to 3,000 IP addresses to connect to the Internet.
If each device was to connect to Internet we would need to have 3,000 IP addresses. At this rate, the 4 billion available IP addresses in IPv4 would have been long exhausted. That is why the invention of NAT solved this.
Instead of each device connecting to the Internet individually, NAT assists us in connecting the office to only 1 public address. The public address is usually configured in the entry router commonly referred to as the Gateway router.
We then generate 3,000 private IP addresses to each of the employee devices. This way, we will have saved 2,999 IP addresses. The invention of NAT greatly delayed the exhaustion of the IPv4 IP addresses. Perhaps, it is the reason why your IP address is still IPv4.
To summarize, Network Address Translation (NAT) is an IP addressing technology that limits the use of public IP address. NAT does so through duplication of IPv4 IPs within a private network.
As a result, a company or institution requires only 1 public IP address regardless of the number of computers in the private network.
Are you aware there are only over 4 billion IPV4 addresses? Consequently, there are more gadgets on the internet than there are IPv4 IPs. Thus, the use of NAT has delayed the exhaustion of IPV4 IP addresses. By the way, the use of IPV6 serves the same purpose.