NAT is a technology that allows multiple devices to share a single public IP address. It's been crucial in extending the lifespan of IPv4, but comes with trade-offs.
Wie NAT funktioniert
NAT sits between your private network and the internet. When a device with a private IP (like 192.168.1.10) connects to the internet, NAT translates its address to the public IP and tracks the connection.
Wenn Antworten zurückkommen, verwendet NAT seine Tracking-Tabelle, um Pakete an das richtige interne Gerät weiterzuleiten. Dies geschieht transparent für ausgehende Verbindungen.
Types of NAT
Different NAT types offer varying levels of accessibility.
SNAT (Source NAT)
Modifies source address for outgoing packets. Standard for home/office networks.
DNAT (Destination NAT)
Redirects incoming traffic to internal servers. Used for port forwarding.
PAT (Port Address Translation)
Uses ports to distinguish connections. Enables many devices to share one IP.
CGNAT (Carrier-Grade NAT)
ISP-level NAT sharing public IPs among multiple customers.
NAT Limitations
While NAT conserves IPv4 addresses, it creates challenges.
- Breaks end-to-end connectivity principle
- Complicates P2P applications and gaming
- Adds latency and processing overhead
- Makes troubleshooting more difficult
- CGNAT prevents inbound connections entirely
Wann Sie eigene öffentliche IPs brauchen
NAT works for outbound-only connections, but many business use cases require direct public IP addresses without NAT complications.
If you're hosting servers, running VPNs, or need reliable inbound connections, dedicated public IPs eliminate NAT-related issues.