Module 3
IPv4 Addressing
Addresses, masks, the arithmetic people actually fail, and the single most common beginner fault - a host that can reach its neighbours but nothing beyond them.
6 activities~63 min
In this module
- Split an IPv4 address into its network and host parts
- Use a subnet mask to decide whether two hosts are on the same network
- Calculate network, broadcast and usable host ranges under time pressure
- Explain what a default gateway is and what breaks without a correct one
Activities
Lesson
IPv4 addresses
Four octets, 32 bits, and what the number actually identifies.
8 min
Lesson
Subnet masks and prefix length
How a mask splits an address into a network and a host.
10 min
Lesson
The default gateway
Where a packet goes when the destination is not local.
7 min
Lab
Lab: local works, remote doesn't
A host can ping its own subnet but nothing outside it. Find the wrong gateway and correct it.
20 min
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Curriculum topics
Each topic page lists every lesson, quiz and hands-on lab that covers it, plus how it maps onto the CCNA and Network+ blueprints.