What is the largest CIDR network subnet block assignable for a VPC?

What is the largest CIDR network subnet block assignable for a VPC?

• A. /20
• B. /18
• C. /16
• D. /14

Answer: (C)

The largest CIDR (Classless Inter-Domain Routing) network subnet block assignable for a VPC (Virtual Private Cloud) is a /16. This means that a /16 subnet provides 65,536 IP addresses (from 0 to 65535) within that subnet, which allows for ample capacity for resources and instances within the VPC. Using a /16 subnet also adheres to the AWS limits for VPCs, which typically provide a range of IP addresses that can adequately support a larger number of resources compared to smaller CIDR blocks. Smaller blocks such as /20, /18, or even /14 could be valid in certain contexts or configurations but would offer fewer usable IPs for a VPC, limiting scalability and resource allocation. Therefore, choosing a /16 subnet block is optimal for networking within a VPC, ensuring maximum flexibility, resource management, and future growth potential. It allows you to create subnets without running out of IP addresses quickly, making it the preferred choice for larger deployments.

The largest CIDR (Classless Inter-Domain Routing) network subnet block assignable for a VPC (Virtual Private Cloud) is a /16. This means that a /16 subnet provides 65,536 IP addresses (from 0 to 65535) within that subnet, which allows for ample capacity for resources and instances within the VPC.

Using a /16 subnet also adheres to the AWS limits for VPCs, which typically provide a range of IP addresses that can adequately support a larger number of resources compared to smaller CIDR blocks. Smaller blocks such as /20, /18, or even /14 could be valid in certain contexts or configurations but would offer fewer usable IPs for a VPC, limiting scalability and resource allocation.

Therefore, choosing a /16 subnet block is optimal for networking within a VPC, ensuring maximum flexibility, resource management, and future growth potential. It allows you to create subnets without running out of IP addresses quickly, making it the preferred choice for larger deployments.