Network Address Translation (NAT)
NAT is another network service that’s used in enterprise networks that allows multiple devices on a local network to access resources on the internet using a single public IP address. NAT acts like a gatekeeper, managing internal requests for access or communication to systems and applications external to the request being made. When data returns from the internet (external systems), NAT manages the reverse process, ensuring the information reaches the correct device.
Note
NAT operates at both Layer 3 and Layer 4 of the OSI model.
How does NAT work?
Imagine a large corporation with thousands of employees working in a headquarters office. The company has a private network with numerous internal servers, workstations, and other devices. The company also has a limited pool of public IP addresses that it obtained from its Internet Service Provider (ISP) (Figure 7.16):
Figure 7.16 – NAT example
Within...
