What is NAT Gateway in AWS? How It Works (Complete Beginner Guide 2026)
Learn what a NAT Gateway in AWS is, how it works, and why it’s used in private subnets. Step-by-step explanation with diagrams, routing, and best practices. Introduction A NAT Gateway is what allows private subnet resources to access the internet securely—without being exposed to it . If you’re building real-world cloud architectures, understanding NAT Gateway is essential. In this guide, you’ll learn: What NAT Gateway is How it works Why it’s used in private subnets Architecture and traffic flow Best practices and common mistakes What is a NAT Gateway in AWS? A NAT (Network Address Translation) Gateway is a managed service that enables instances in a private subnet to connect to the internet for outbound traffic, while preventing inbound connections. In Amazon Web Services , NAT Gateway is: Fully managed Highly available within an Availability Zone Automatically scalable Simple Definition A NAT Gateway allows private servers to access the internet without exposing t...