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A Brief Overview of NAT – Network Address Translation

What is NAT and how does it ‘translate’ an address?

NAT stands for network address translation; this is a process of modifying an IP packet as it transits a network.  This involves a router or firewall modifying the IP information in packets that are passed through the network boundary that is performing the address translation. The most common use of NAT is to translate a private address to a public addresses at a firewall/router, which separates an intranet network from the internet. As traffic originates from the internal side of the network boundary, the IP information in the packet is changed to a public IP address that is routable on the internet. Once traffic returns to the firewall, the NAT translations table that is stored on the device maps the public IP back to the private IP address, and forwards the information to the correct internal IP address that requested it.

While you can do different types of NATing, the most widely used configurations are dynamic NAT and static NAT. The most Continue reading A Brief Overview of NAT – Network Address Translation