A technician needs to configure a virtual NIC on a Class A IP address network. What is the default subnet mask for this network?

A technician needs to configure a virtual NIC on a Class A IP address network. What is the default subnet mask for this network?

• A. /8
• B. /16
• C. /24
• D. /28

Answer: (A)

In IPv4, classful addressing assigns a default subnet mask based on the IP class. For a Class A address, the default mask uses the first octet for the network, giving 8 bits for the network portion, i.e., 255.0.0.0, which is /8. This means the network is identified by the first octet while the remaining 24 bits are for hosts. The other options would be the defaults for Class B (255.255.0.0, /16) or Class C (255.255.255.0, /24), or represent a subnet mask that’s more specific than the default (like /28).

In IPv4, classful addressing assigns a default subnet mask based on the IP class. For a Class A address, the default mask uses the first octet for the network, giving 8 bits for the network portion, i.e., 255.0.0.0, which is /8. This means the network is identified by the first octet while the remaining 24 bits are for hosts. The other options would be the defaults for Class B (255.255.0.0, /16) or Class C (255.255.255.0, /24), or represent a subnet mask that’s more specific than the default (like /28).