Networking & Internet
NAT
Definition
Network Address Translation (NAT) is a method of remapping an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device.
Why It Matters
NAT is the technology that allows your entire home network, with many devices (each with its own private IP address), to share a single public IP address provided by your ISP. It was a crucial workaround for the exhaustion of IPv4 addresses.
Contextual Example
When your computer (with private IP 192.168.1.100) sends a request to Google, your home router performs NAT. It replaces the source address with its own public IP address and forwards the request. When the response comes back, the router knows to send it to your computer.
Common Misunderstandings
- NAT also provides a basic level of security, as it hides the internal network structure from the outside world.
- NAT can cause problems for some applications, like peer-to-peer gaming or file sharing, that require direct incoming connections.