NAT

Network Address Translation (NAT)

See how NAT rewrites private IP addresses to public ones, conserving IPv4 addresses and hiding internal network structure.

What is an IP Address?

An IP address is a numeric label assigned to every device on a network so it can be uniquely identified and reached — IPv4 uses a 32-bit address written as fou…

What is NAT (Network Address Translation)?

NAT (Network Address Translation) is a technique that maps multiple private IP addresses on an internal network to one or a few public IP addresses, allowing m…

IPv4 vs IPv6: What Are the Differences?

IPv4 uses 32-bit addresses giving about 4.3 billion possible addresses, while IPv6 uses 128-bit addresses giving a practically unlimited pool, and IPv6 also si…

What is TCP Keepalive and How Does It Work?

TCP keepalive is an optional mechanism where an idle connection periodically sends a small probe segment to check whether the peer is still reachable and the c…

Private vs Public IP Addresses

A public IP address is globally unique and directly routable across the internet, while a private IP address comes from reserved ranges (like 10.0.0.0/8 or 192…

What is a Network Gateway?

A network gateway is the node — usually a router — that sits at the boundary of a local network and provides the exit point to a different network, most common…

What is a Modem and How Does It Differ from a Router?

A modem (modulator-demodulator) is the device that converts digital data from your home network into the analog or carrier signal format used by your ISP’s tra…

What is NAT Traversal?

NAT traversal refers to the set of techniques that let two devices establish a direct peer-to-peer connection even though one or both sit behind a NAT (Network…

What is Port Forwarding and How Does It Work?

Port forwarding is a router/NAT configuration that maps an incoming connection on a public IP address and port to a specific private IP address and port inside…

What is NAT and Port Translation (NAPT)?

NAT (Network Address Translation) is the process a router or gateway uses to rewrite the source or destination IP address of a packet as it crosses network bou…

What is Carrier-Grade NAT (CGNAT)?

Carrier-Grade NAT (CGNAT) is a large-scale form of network address translation that an ISP runs in its own network to share a small pool of public IPv4 address…