What is NAT (network address translation)?

NAT (network address translation) is the technique a router uses to let many devices with private addresses share one public internet address. When a PC in your office connects to a website, the router replaces the PC's private address with its own public one and remembers which reply belongs to which device. NAT is why your office devices are not directly reachable from the internet by default, which helps, but it is not a firewall: port forwarding rules can deliberately open a path inward. For investigations, NAT means outside parties only see the router's address, so your own logs must show which inside device it was.

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