IP Addresses and Subnetting

Explore decimal base-10 and binary base-2 numbering systems, using positional notation with digits 0–9 and 0–1 to build numbers like 523.

Learn how to convert a decimal number to binary and back, using division by two and binary weights, illustrated with 58 and cross-checked on Windows calculator.

Master binary to decimal conversion through step-by-step examples that sum powers of two, such as 32,16,8,4,2,1. Apply this skill to understand binary numbers for subnetting and IP addresses.

Explore the special loopback address 127.0.0.1, used by the IP stack to talk to the local machine, enabling local testing and self-communication.

Learn how subnetting borrows four host bits to form sixteen subnets with twenty host bits per subnet in an IPv4 class A network.

Explore class B subnetting by borrowing three bits from the host portion of 172.16.0.0, creating eight subnets and about 65,534 usable addresses per subnet.

Discover class B subnetting by borrowing host bits, applying the default 255.255.0.0 mask and the 255.255.224.0 subnet mask, and deriving subnet IDs, broadcast addresses, and IP ranges.

Explore calculating subnets for a Class A network using Excel, deriving a 16-subnet scheme from 10.0.0.0, determining the subnet mask, ranges, and broadcast addresses.

Explore the three formats of subnet masks, decimal dotted notation, binary, and prefix slash notation, covering class a, b, and c masks and how network bits define ranges.