Which platform is used to provide internet access to an OCI compute instance in a private subnet?

To understand why the Internet Gateway is the correct answer for providing internet access to an OCI compute instance in a private subnet, it is important to recognize the roles of different OCI networking components.

An Internet Gateway serves as a conduit for resources within a virtual cloud network (VCN) to connect to the public internet. By attaching an Internet Gateway to the VCN, any resource configured to use a public subnet can send and receive traffic over the internet. However, in the context of a compute instance located in a private subnet, it's important to note that the Internet Gateway itself does not directly provide internet access to instances in that private subnet.

Instead, for a compute instance in a private subnet to access the internet, it typically requires a different approach. The correct means of providing such access is through a Service Gateway or a NAT (Network Address Translation) Gateway, which allows outbound internet access while keeping the instances hidden from direct internet incoming traffic.

The Service Gateway enables connections to Oracle services without routing traffic over the internet, while a NAT Gateway specifically facilitates internet access from private subnets. Both enable secure internet access for resources not directly reachable via an Internet Gateway.

To summarize, the Internet Gateway allows for incoming and outgoing internet traffic to resources in public subnets,