Visual lab

Learn subnetting visually

11 short lessons, from binary to IPv6. Change the inputs and watch every value update.

Lesson 7 of 11Intermediate

Across octets

Find the interesting octet, count by the block size there, and every octet to its right goes to 0 for the network and 255 for the broadcast.

FixedSteps by block sizeSweeps 0 to 255

/25 – /32

The first three octets stay fixed. Only the last octet moves, between 0 and 255.

Address

192.168.1.50/26

Block size 64 in octet 4

Network

19216810

Broadcast

192168163

/17 – /24

The first two octets stay fixed. The third moves by the block size; the fourth sweeps 0 to 255.

Address

172.16.45.100/20

Block size 16 in octet 3

Network

17216320

Broadcast

1721647255

/9 – /16

Only the first octet stays fixed. The second moves by the block size; the last two sweep .0.0 to .255.255.

Address

10.75.12.8/12

Block size 16 in octet 2

Network

106400

Broadcast

1079255255

Drill the “Interesting octet” skill until it is automatic.

Lesson 7 of 11

Next: Design with VLSM