CompTIA Network+ Practice Test 2025 – Comprehensive Exam Prep

The subnet mask for a Class B IP address is 255.255.0.0. This designation indicates that the first two octets of an IP address are used for the network portion, while the last two octets are designated for host addresses within that network.

Class B addresses range from 128.0.0.0 to 191.255.255.255, and the default subnet mask, 255.255.0.0, allows for a significant number of possible hosts on a network. Specifically, with this subnet mask, you can have up to 65,534 hosts per network segment, as each of the last two octets (8 bits each) can vary independently, providing substantial flexibility for subnetting.

In this context, other subnet masks listed are not appropriate for a Class B address. For example, 255.0.0.0 is the default subnet mask for a Class A address, while 255.255.255.0 is the default for a Class C network, which is designed for smaller networks with fewer hosts. Finally, 255.255.255.255 is a special broadcast address and not a traditional subnet mask at all. Thus, 255.255.0.