With a subnet mask of 255.255.255.0, which portion of an IPv4 address is the host portion?

With a subnet mask of 255.255.255.0, which portion of an IPv4 address is the host portion?

• A. The host portion is the last octet.
• B. The host portion is the first octet.
• C. The host portion is the middle two octets.
• D. There is no host portion.

Answer: (A)

With a subnet mask of 255.255.255.0, the first 24 bits are the network portion and the last 8 bits are the host portion. That means the network is defined by the first three octets, and the last octet identifies the specific device on that network. For example, in 192.168.1.42, the network part is 192.168.1, and the host part is 42. Usable host addresses typically range from 192.168.1.1 to 192.168.1.254, with 192.168.1.0 as the network address and 192.168.1.255 as the broadcast address.

With a subnet mask of 255.255.255.0, the first 24 bits are the network portion and the last 8 bits are the host portion. That means the network is defined by the first three octets, and the last octet identifies the specific device on that network. For example, in 192.168.1.42, the network part is 192.168.1, and the host part is 42. Usable host addresses typically range from 192.168.1.1 to 192.168.1.254, with 192.168.1.0 as the network address and 192.168.1.255 as the broadcast address.