NAT (Network Address Translation) is a process for changing source and destination IP addresses and ports. Address translation reduces the need for IPv4 public addresses and hides private network address areas. The process is usually done by routers or firewalls.
There are three types of addressing:
1. Static NAT - translates a private IP address into a public one. The public IP address is always the same.
2. Dynamic NAT-Private IP addresses are assigned to the pool by public IP addresses.
3. Port Address Translation (PAT) - A public IP address is used for all internal devices, but each private IP address is assigned another port. Also known as NAT Overload.
An example helps you understand the concept.
Night example
Computer A requests a web page from an Internet server. Because computer A uses private IP addressing, the source address of the request must be changed by the router as private IP addresses on the Internet are not routable. The router R1 receives the request, changes the source IP address to its public IP address, and sends the packet to the server S1. Server S1 receives the packet and the answers to the router R1. The router R1 receives the packet, changes the destination IP addresses to the private IP address of computer A and sends the packet to computer A.
There are three types of addressing:
1. Static NAT - translates a private IP address into a public one. The public IP address is always the same.
2. Dynamic NAT-Private IP addresses are assigned to the pool by public IP addresses.
3. Port Address Translation (PAT) - A public IP address is used for all internal devices, but each private IP address is assigned another port. Also known as NAT Overload.
An example helps you understand the concept.
Night example
Computer A requests a web page from an Internet server. Because computer A uses private IP addressing, the source address of the request must be changed by the router as private IP addresses on the Internet are not routable. The router R1 receives the request, changes the source IP address to its public IP address, and sends the packet to the server S1. Server S1 receives the packet and the answers to the router R1. The router R1 receives the packet, changes the destination IP addresses to the private IP address of computer A and sends the packet to computer A.