Question

You need to subnet a network that has 5 subnets, each with at least 16 hosts. Which classful subnet mask would you use?A. 255.255.255.192B. 255.255.255.224C. 255.255.255.240D. 255.255.255.248

Answer 1

B. 255.255.255.224

Step-by-step explanation:

Subnetting in networking is a process of reducing the number of wasted IP addresses used in a network. There are three major classes of IP address, they are, Class A, B, and C with respective network addresses of 1,2, and 3 octets of the subnet mask.

255.255.255.0 is a class C IP address, it only has one subnet mask and 256 host address. In a network of 16 to 30 hosts, 226 to 240 addresses would be wasted. Subnetting the address to have five subnets reduces the IP addresses used.

The new subnet mask becomes 255.255.255.224 borrowing 3 bits from the fourth octet to give 8 subnet masks and 30 host IP addresses.