CCNA Introduction to Networks (ITN) Practice Test 2026 - Free CCNA ITN Practice Questions and Study Guide

To determine the subnet mask that provides the maximum number of equal size subnets within the address block of 128.107.0.0/16, it's important to analyze the effect of different subnet masks on the number of available subnets.

The notation /16 indicates that the first 16 bits of the address are used for the network portion, while the remaining bits are available for host addresses. In this case, the default subnet mask is 255.255.0.0.

When you apply a subnet mask such as 255.255.255.0, you're increasing the size of the subnet mask to /24. This allows for 256 subnets (since 2^(24-16)=2^8=256) but limits the number of host addresses per subnet to 254.

If you choose a subnet mask of 255.255.255.128, you're using /25. This allows for 512 subnets (2^(25-16)=2^9=512) but reduces the number of host addresses per subnet to 126.

A mask of 255.255.254.0, which corresponds to /23, will provide 128 subnets (2^(23-16)=2^7