Computer Network Tutorial: Static NAT, Dynamic NAT, PAT 🎯

Welcome to our comprehensive guide on Static NAT, Dynamic NAT, and PAT (Port Address Translation)! 📝

In this tutorial, we'll explore these essential network address translation (NAT) techniques that allow multiple private IP addresses to access the internet using a single public IP address. Let's dive in!

Understanding Network Address Translation (NAT) 📝

NAT is a technique used in networking to modify the headers of IP packets as they enter or leave a private network. It helps manage the scarcity of public IP addresses and provides security benefits by hiding internal network information.

Private vs Public IP Addresses 📝

Before we dive into Static NAT, Dynamic NAT, and PAT, let's first understand the difference between private and public IP addresses.

• Public IP addresses are unique addresses that identify devices on the internet. They are globally unique and can be accessed by anyone.
• Private IP addresses, on the other hand, are used within a private network and are not globally unique. They are used for communication between devices on the same network.

Static NAT 💡

Static NAT, also known as one-to-one NAT, is a method that assigns a specific public IP address to a specific private IP address. This method is typically used for dedicated servers, VPN servers, or when you want to make a specific device accessible from the internet.

Example: Static NAT Configuration 💡

Let's consider an example where our private network has the IP range 192.168.1.0/24 and the public network has the IP range 10.0.0.0/8. If we want to make our server at 192.168.1.5 accessible from the internet, we would statically map it to a public IP address, say 10.0.0.100.

Private Network: 192.168.1.0/24 Public Network: 10.0.0.0/8 Server IP: 192.168.1.5 Public IP: 10.0.0.100

Dynamic NAT 💡

Dynamic NAT, also known as pooled NAT, is a method that assigns a public IP address from a pool of available addresses to a private IP address dynamically. This method is used when multiple devices need access to the internet, but a specific public IP address is not required for each device.

Example: Dynamic NAT Configuration 💡

In our previous example, instead of statically mapping 192.168.1.5 to a specific public IP, we could create a pool of public IP addresses and assign one from the pool to our server dynamically each time it requests access to the internet.

Private Network: 192.168.1.0/24 Public Network: 10.0.0.0/8 Public IP Pool: [10.0.0.101 - 10.0.0.120] Server IP: 192.168.1.5

Port Address Translation (PAT) 💡

PAT, also known as overload NAT, is a method that uses a single public IP address and translates the port number of each outgoing request to a different port number on the public IP address. This method is used when a large number of devices need access to the internet, and public IP addresses are scarce.

Example: PAT Configuration 💡

In our previous examples, we were using a separate public IP address for each device. With PAT, we can use a single public IP address and allow multiple devices to access the internet simultaneously.

Private Network: 192.168.1.0/24 Public Network: 10.0.0.1 Server 1 IP: 192.168.1.5 Server 2 IP: 192.168.1.6 Server 1 Requests: Port 10000 Server 2 Requests: Port 10001

Quiz 📝