Definition of Network Address Translation (NAT) - Inget Lirik

Understanding Network Address Translation (NAT) - On this occasion I will provide an article about what NAT is or stands for Network Address Translation, which is commonly known as Network Address Interpretation. Hopefully this article is useful for all of you.

What is NAT?

Network address translation (English: Network Address Translation) is a method of connecting more than one computer to the internet network using a single IP address. The many uses of this method are due to the limited availability of IP addresses, the need for security, and the ease and flexibility of network administration.

Many of us or our friends are still confused about understanding this NAT. Therefore, I will provide materials about this NAT so that all friends can more easily understand the material.

Definition of Network Address Translation (NAT)

NAT (Network Address Translation) is a process of mapping IP addresses where computer network devices will provide public IP addresses to local network devices so that many private IPs can access public IPs.

In other words NAT will translate the IP address so that the IP address on the local network can access the public IP on the WAN network. NAT translates private IP addresses to be able to access host addresses on the internet by using public IP addresses on the network. Without this (NAT) it is impossible for private IPs on the local network to access the internet.

Functions of Network Address Translation (NAT)

NAT (Network Address Translation) on a computer network functions as a translation of public IP addresses to private IP addresses or vice versa so that with this NAT every computer on the LAN network can easily access the internet.

We know that Public IP addresses in this world are getting depleted, so the use of NAT is considered very efficient and effective, especially in IP address allocation.

Types of Network Address Translation (NAT)

In a computer network there are 2 types of NAT, including the following:

1. NAT

• Dnat or Destiantion Network Address Translation> a NAT which functions to forward packets from public IP through the firewall to a host in the network. Dnat only works on the NAT table and in the NAT table it contains 3 parts which are called CHAIN, the three CHAINs include prerouting, postrouting and output.
• Redirect> to redirect the connection that was passing through the router and redirected to Localhost.

2. NAT

• SNAT or Source Network Address Translation> a NAT that can change the source address of a data packet. SNAT only works for postrouting, or it can also be interpreted as filling in the local IP address and replacing it with the public IP address already installed on the router.
• Masquerade > will automatically use the IP Address on the Public Interface. Used to facilitate installation and when the Public IP Address on the Public Interface uses a dynamic IP Address (eg DHCP, PPTP or EoIP).

Pros and Cons of Network Address Translation (NAT)

A system will certainly have advantages and disadvantages, so by understanding the strengths and weaknesses of the system we can know why we should use it or not use it. Here are the advantages and disadvantages of using NAT on a network, as follows:

Advantages of Network Address Translation (NAT)

• With NAT, it can reduce the duplication of IP addresses on the network or commonly known as IP Address conflict
• With NAT, it will avoid re-addressing when the network changes.
• Can save legal IP provided by the ISP (Internet Service Provider)
• Can increase flexibility for internet network connections.

Weaknesses of Network Address Translation (NAT)

• NAT can cause process delays, this is because the data sent must go through the NAT device first.
• NAT can cause some applications not to run normally
• NAT can eliminate the ability to track data because the data will pass through the firewall.

How Network Address Translation (NAT) Works

NAT has a function, namely as a translation of an IP address, so that with this NAT private IP addresses can easily access public IP addresses. Here is how NAT works, including:

1. In the IP address there is a part where in the IP there is information in the form of the origin address, destination address, TTL, etc. This section is called the header.
2. For example, a client computer with IP 192.168.1.2 will access or make a request to the www.google.co.id address with IP 216.239.61.104, then the process that will occur is as follows:
3. In the header, the information stored includes origin address> 192.168.1.2
4. So that when the packet arrives at the router (gateway from the client), the contents of the header will be changed to: origin address> 192.168.1.1
5. Before the packet goes out (to the internet), the header will change back to, origin address> 200.100.50.2, and so on.
6. The above process is a mechanism from SNAT (source NAT), where the original IP (client computer) will be changed according to the IP when the packet has moved. When the google server responds, a DNAT (destination NAT) will occur, where the destination IP will change according to the destination of the packet (client computer). The process is as follows:
7. In the header, when the packet has arrived at the router, the destination IP information is> 200.100.50.20
8. When the packet is on the gateway, the destination IP is> 192.168.1.1
9. Here the header will change again, destination IP> 192.168.1.2
10. So that packages can be sent and can arrive at the client computer.

Conclusion

NAT (Network Address Translation) on a computer network functions as a translation of public IP addresses to private IP addresses or vice versa so that with this NAT every computer on the LAN network can easily access the internet.

That's all for our article this time about the discussion of Network Address Translation (NAT) if you have problems or questions about the article above, please comment in the comments column, more and less we apologize profusely.