NAT Explained
How Multiple Devices Share One Public IP
NAT (Network Address Translation) allows many devices in a private network to use a single public IP address to access the internet.
Why NAT exists
IPv4 addresses are limited. NAT solves this by:
- Using private IP ranges internally
- Translating them to one public IP externally
How NAT works
- Device sends traffic to router
- Router replaces private IP with public IP
- Router tracks connections using ports
- Replies are mapped back correctly
Why NAT matters
- Enables home networks
- Adds basic security by hiding internal IPs
- Makes IPv4 internet scalable