Question

A network on the Internet has a subnet mask of 255.255.240.0. What is the maximum number of hosts it can handle ?

Answer 1

Subnet Mask: 255.255.240.0

It is a class B network. For a class B network, the upper 16 bits form the network address and lower 16 bits are subnet and host fields.

Of the lower 16 bits most significant 4 bits are 1111. This leaves 12 bits for the host number. So, 4096(2¹²) host address exists.

First and Last address are special so the maximum number of address = 4096 - 2 = 4094.