Which component helps define the size of the local network by specifying which portion of an IP address is the network address?

Which component helps define the size of the local network by specifying which portion of an IP address is the network address?

• A. IP address
• B. Subnet mask
• C. DNS server IP
• D. Gateway IP

Answer: (B)

Defining the size of the local network comes from identifying which portion of an IP address designates the network itself. The tool that marks this boundary is the subnet mask. It indicates which bits are fixed for the network and which bits can vary for hosts. By applying the subnet mask to an IP address, you derive the network address, which tells you the network’s range and how many host addresses are available. For example, a mask of 255.255.255.0 on a 192.168.1.x address space yields a /24 network, meaning 256 addresses in that local network. The other items don’t define network size: the IP address alone doesn’t specify how many bits belong to the network portion; DNS server IP is used for resolving domain names, and the gateway IP is the router’s address used to reach destinations outside the local network.

Defining the size of the local network comes from identifying which portion of an IP address designates the network itself. The tool that marks this boundary is the subnet mask. It indicates which bits are fixed for the network and which bits can vary for hosts. By applying the subnet mask to an IP address, you derive the network address, which tells you the network’s range and how many host addresses are available. For example, a mask of 255.255.255.0 on a 192.168.1.x address space yields a /24 network, meaning 256 addresses in that local network. The other items don’t define network size: the IP address alone doesn’t specify how many bits belong to the network portion; DNS server IP is used for resolving domain names, and the gateway IP is the router’s address used to reach destinations outside the local network.