Uploaded February 2026 | Updated September 2026, 6 hours ago

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I was at work when my IT manager dropped an urgent request in my inbox —
Design a new IP addressing scheme for 7 networks in one hour. This is
exactly what happened, and how I solved it using VLSM (Variable Length
Subnet Masking.

In this video, you'll learn:

✅ How to identify how many subnets and hosts you need
✅ The #1 VLSM rule — always start with the largest subnet
✅ How to use the subnetting cheat chart for fast calculations
✅ How to allocate /25, /27, and /30 subnets efficiently

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Read my free VLSM guide here - howtonetwork.com/free-ccna-study-guide-ccna-book/learn-ip-addressing/#VLSM

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📌 Chapters:
00:00:00 - Introduction - The Urgent Request
00:00:40 The network diagram — 7 subnets needed
00:01:15 - Rule #1 — start with the largest subnet
00:01:28 - The subnetting cheat chart
00:01:38 - The large LAN
00:02:52 - The three LANs
00:03:51 Solving the WAN links (/30)
00:04:21 Everything fits — the final design

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#VLSM #Subnetting #CCNA #NetworkPlus #IPAddressing #Networking