NATGateway

**NATgateway**

NATgateway is a service provided by Amazon Web Services (AWS) that enables customers to create a network address translation (NAT) gateway to allow instances running on an Amazon Elastic Compute Cloud (EC2) public subnet to access the internet and communicate with other AWS services. It acts as a proxy, translating private IP addresses to public ones and facilitating outbound and inbound traffic between instances and the internet.

The NATgateway is designed to be highly available and durable, with redundancy across multiple Availability Zones (AZs) within a single region. This redundancy ensures that instances in the subnet can maintain connectivity even if one AZ becomes unavailable. NATgateways are managed by AWS and do not require manual configuration of routing tables or IP addresses.

A NATgateway is typically deployed in a public subnet within a Virtual Private Cloud (VPC). It is associated with a route table that directs traffic destined for the internet through the NATgateway. Instances in the private subnet can then access the internet by sending their traffic to the NATgateway, which forwards it out to the internet and returns the response. This setup is particularly useful for instances that require outbound access but do not need to be directly accessible from the internet.

AWS provides a NATgateway with a public Elastic IP address, which can be used to manage the gateway. This Elastic IP is automatically associated with the NATgateway and can be reassigned if needed. NATgateways are charged based on the amount of data transferred out to the internet, with pricing details available on the AWS Pricing Calculator.

Before deploying a NATgateway, it is important to ensure that the subnet is configured with a default route pointing to the NATgateway and that the security groups associated with the instances allow outbound traffic to the internet. Additionally, NATgateways have a maximum outbound bandwidth limit, which can be increased if necessary by contacting AWS Support.