IPv4 Subnetting and Network Design

Who It Is For

Engineers revising for CCNA or Network+, help desk staff stepping up to networking and anyone who has to plan an addressing scheme and wants to do it once. If you can already subnet in your head, skip to the assessment. This is our own course, not affiliated with Cisco or CompTIA.

The Lessons

1. Binary and the Dotted Quad. Read an octet in binary and back again, the skill every other lesson leans on. About 10 minutes.
2. Masks, Prefixes and Wildcards. Move between /26, 255.255.255.192 and 0.0.0.63 without reaching for a table. About 10 minutes.
3. Network, Broadcast and Host Ranges. Find the block an address sits in, then its first and last usable hosts. About 15 minutes.
4. Sizing Subnets. Work out how many hosts a prefix gives and the smallest prefix a VLAN needs. About 10 minutes.
5. Splitting a Block With VLSM. Cut a /24 into subnets of different sizes, in order, with no overlaps. About 15 minutes.
6. Summarising Routes. Collapse contiguous networks into one route, and know when you should not. About 10 minutes.
7. Special Ranges and Design Rules. The ranges you must recognise on sight, point to point links and the choices that age well. About 15 minutes.

The Assessment

• 30 questions drawn at random from every lesson, different for every attempt.
• 45 minutes. The clock starts when you press start.
• Pass mark 80 per cent: 24 of 30.
• A pass completes the course. The lessons are there to help; they are not required.

Go to the assessment.

Tools You Will Use

• The subnet calculator, to check your working.
• The route summariser, for lesson six.
• Our IPv4 design guide, for lesson seven.