AWS (Amazon Web Services) Certification Practice Exam

Why are subnets used within a VPC?

1. To allow direct internet access to all resources

2. To segment the VPC infrastructure into different networks

3. To automatically scale resources

4. To enhance reporting and analytics capabilities

The correct answer is: To segment the VPC infrastructure into different networks

Subnets are essential in a Virtual Private Cloud (VPC) because they function to segment the VPC infrastructure into distinct networks, creating separate logical unit divisions. This segmentation allows you to isolate resources based on various criteria, such as security needs, application types, or stages of development (e.g., production, staging, development). By organizing resources into different subnets, you can apply more specific security groups and network access control lists (ACLs) to each subnet, enhancing security around those resources. Additionally, subnets can be designated as either public or private. Public subnets can have resources that require direct access to the internet, while private subnets can host resources that do not need direct internet access. This approach helps in managing traffic and resources more effectively within the VPC. The other options focus on aspects that are either not directly related to the primary function of subnets or do not accurately represent the capabilities of VPCs. Subnets do not inherently provide direct internet access to resources, scale resources automatically, or enhance reporting and analytics capabilities on their own. These functionalities stem from other AWS components and services that work in conjunction with the VPC and subnets.