Networking guides
Short, clear explainers on the concepts behind the calculators. No filler, no "in today's digital world", just the ideas you need to subnet with confidence.
What is a subnet?
A subnet is a smaller network carved out of a larger IP network. Subnetting lets you split one address block i...
What is a subnet mask?
A subnet mask is a 32-bit number that separates the network part of an IP address from the host part. A mask l...
What is CIDR notation?
CIDR (Classless Inter-Domain Routing) is the modern way to describe an IP block using a prefix length, like 19...
VLAN vs subnet: what is the difference?
A VLAN and a subnet solve related problems at different layers. A VLAN separates traffic at layer 2 (switching...
Subnet masks worth memorising
This is the short list every network engineer ends up knowing by heart: the subnet mask, wildcard mask, and us...
How to calculate a subnet mask
Calculating a subnet mask is a short, mechanical process once you know the steps: count the hosts you need, fi...
Classful vs classless addressing
Classful and classless are two different ways of deciding where the network part of an IPv4 address ends and t...
Private vs public IP addresses
A private IP address only means something inside your own network; a public IP address is unique and routable ...