A NAT (Network Address Translation) gateway is a network service that enables instances in a private subnet to connect to the internet or other AWS services while preventing inbound traffic from the internet to those instances. It acts as a bridge between the private and public networks, translating private IP addresses to public IP addresses.
Explanation:
- Private Subnet: A subnet where instances do not have a direct route to the internet.
- Public Subnet: A subnet where instances have a direct route to the internet and can be accessed from the internet.
How it works:
- Outbound Traffic: When an instance in a private subnet sends traffic to the internet, the NAT gateway translates the private IP address of the instance to its own public IP address and forwards the traffic.
- Inbound Traffic: The NAT gateway does not allow inbound traffic from the internet to the instances in the private subnet, enhancing security.
Example:
- You have a web server in a public subnet and a database server in a private subnet.
- The database server needs to access updates from the internet, but you don't want it to be directly accessible from the internet.
- The NAT gateway allows the database server to initiate outbound connections to the internet for updates while blocking any inbound requests.
Recommended Service:
For implementing NAT gateways in the cloud, Tencent Cloud offers the NAT Gateway service, which simplifies the configuration and management of network address translation, providing secure and efficient outbound internet access for resources in private subnets.