What type of instance is required to allow NAT functionality in a VPC?

To enable NAT functionality in a Virtual Private Cloud (VPC), the correct choice refers to a public EC2 instance. A public EC2 instance receives a public IP address, which allows it to communicate directly with the internet. This is a key requirement for functioning as a NAT (Network Address Translation) instance.

When this instance is configured correctly, it can allow instances in a private subnet to access the internet while preventing inbound traffic initiated by external sources. By routing traffic from the private subnet through the public EC2 instance, resources in that private subnet can initiate outbound connections to the internet (for software updates, API calls, etc.) and receive responses, while remaining inaccessible directly from the internet.

It is important to configure the routing table for the private subnet to direct traffic destined for the internet to the public EC2 instance configured as the NAT. Additionally, security group settings must allow the necessary traffic as well.

Other options do not fulfill the requirement as effectively. A private EC2 instance does not have a public IP, making it unable to directly reach the internet. A dedicated NAT gateway, while indeed providing NAT functionality, is a managed service which differs from using a public EC2 instance. An elastic load balancer is designed to distribute incoming application traffic across