Subnet Trainer

For a random IPv4 address + mask (e.g. 178.178.178.178/24), answer three things:

• Class — is the address Class A, B, or C?
• Scope — is the mask the class's default, a subnet (longer than default), or a supernet (shorter than default — aggregating multiple classful networks, e.g. 193.15.4.7/16 is one address in a block made from 256 Class C networks)?
• Type — is it a network, broadcast, or host address?

Quick reference

• Class A: 1.0.0.0 – 126.255.255.255, default mask /8
• Class B: 128.0.0.0 – 191.255.255.255, default mask /16
• Class C: 192.0.0.0 – 223.255.255.255, default mask /24
• Network address = all host bits 0 · Broadcast = all host bits 1
• Usable hosts = network address + 1 → broadcast address − 1
• Supernet = mask shorter than the class default, aggregating 2^n classful networks into one block (e.g. /16 over a Class C address combines 256 Class C networks)