What does a network address consisting of all zeros indicate?

• A. It represents the network itself
• B. It represents the broadcast address
• C. It represents a single host
• D. It represents the default gateway

Answer: (A)

In IPv4, the network address is identified by keeping the network portion and setting the host portion to zero. An address with all host bits zero marks the entire subnet, not a single device. For example, in a 192.168.10.0/24 network, 192.168.10.0 is the network address that identifies the whole 192.168.10.0/24 subnet. The broadcast address for that same subnet would be 192.168.10.255, used to reach every device on the subnet, while a specific host would have a nonzero host portion like 192.168.10.5. The default gateway is just the router’s IP within the subnet, not the network address itself.