Missiora
IP Addressing & Subnetting

Technology Fundamentals

IP Addressing & Subnetting

2 min readPublished 22 Jul 2026

IP addressing is how every device on a network is identified, and subnetting is how large networks are divided into efficient, manageable pieces.

Interactive explainer

IP Addressing & Subnetting

How one address splits into a network part and a host part.

Octet 1192Octet 2168Octet 31Octet 40Network (/24)Hosts (254)Mask 255.255.255.0 = /24Split /24 into two /25s (128 addresses each)

Tap or hover a part to learn more.

Network portion

Identifies the network.

In 192.168.1.0/24 the first 24 bits (192.168.1) are the network portion — every device on this network shares them. All hosts in the same subnet have an identical network part.

Check your understanding

1. How many usable hosts are in a /24?

2. What does the /24 in 192.168.1.0/24 represent?

Keep learning

IP Addressing & SubnettingNetworking Fundamentals CompTIA Network+
Practise this in AI Interview™

The core idea

  • IPv4 (e.g. 192.168.1.10) is 32-bit; IPv6 (e.g. 2001:db8::1) is 128-bit for far more addresses.
  • Private ranges (10.x, 172.16–31.x, 192.168.x) are reused inside networks; public IPs are globally unique.
  • A subnet mask (or CIDR /24) splits an address into network and host portions.

How it works in practice

  • /24 = 256 addresses (254 usable); /25 splits that in half.
  • The gateway is usually the first usable address in the subnet.
  • APIPA (169.254.x.x) means DHCP failed to assign an address.

Common mistakes

  • Confusing the network address and the usable host range.
  • Overlapping subnets that cause routing problems.
  • Assuming a device with an APIPA address has a working connection.

Why it matters for your career

Subnetting is a classic interview and exam topic — being able to work out ranges quickly is a strong signal for any networking role.

Technical interview questions

  1. What is the difference between a private and public IP?
  2. What does a /24 subnet mask mean?
  3. How many usable hosts are in a /24?

Practice questions

  1. How many usable hosts in a /24? (254)
  2. Is 10.0.0.5 public or private? (Private)
  3. What does 169.254.x.x indicate? (DHCP failure (APIPA))

Where this fits in your networking journey

This is one concept in the Networking Fundamentals path, which leads into CompTIA Network+ and Cisco CCNA. When this clicks, review Ethernet & Switching Basics and continue with Switching & VLANs.

Practise with Missiora

Interview Intelligence

How this topic actually shows up in interviews — and how to demonstrate you understand it.

Why employers ask about this

Subnetting is a classic interview filter; interviewers test whether you can reason about address space quickly.

Technical questions
How many usable hosts are in a /24?+

254 (256 minus the network and broadcast addresses).

What does the subnet mask do?+

It marks which bits of an address are network and which are host.

Behavioural questions
Describe explaining subnetting to someone new.+

Break it into network vs host portions with a simple example.

Real-world scenarios
“Two devices on '192.168.1.x' can't communicate.”+

Expected answer: Check for mismatched subnet masks or overlapping/incorrect addressing.

Common candidate mistakes
  • •Miscounting usable hosts.
  • •Overlapping subnets.
Practise these in AI Interview™Rehearse these questions out loud and get instant feedback.Plan your route with Career Coach™Turn this topic into a personalised learning and career plan.

Employability Intelligence

Where this knowledge takes you — the jobs, skills and certifications it feeds into.

Relevant roles
Network AdministratorNetwork Support
Skills you're proving
IP addressingSubnettingCIDR
Recommended certifications
CompTIA Network+
Career progression

Network Support → Network Administrator.

What employers expect

That you can subnet confidently under pressure.

Frequently asked questions

What is ip addressing & subnetting in networking?

IP addressing is how every device on a network is identified, and subnetting is how large networks are divided into efficient, manageable pieces.

What is the difference between a private and public IP?

IPv4 (e.g. 192.168.1.10) is 32-bit; IPv6 (e.g. 2001:db8::1) is 128-bit for far more addresses. Private ranges (10.x, 172.16–31.x, 192.168.x) are reused inside networks; public IPs are globally unique.

Do I need this for Network+ or CCNA?

Yes — IP Addressing & Subnetting is a core concept in CompTIA Network+ and Cisco CCNA. Understanding it here first makes the certification material much easier.

Related guides

Networking Fundamentals: The Complete Free Vendor-Neutral GuideEthernet & Switching BasicsSwitching & VLANsThe OSI Model Explained

Practise what you've learned

Turn this guide into real, evidenced progress

Missiora helps you measure, improve and evidence the capabilities employers actually value — start with the tools best suited to this topic.

M
Published by
Missiora

Missiora is an AI Employability Intelligence platform. Our resources are researched and reviewed by the Missiora team to help you measure, improve and prove your career readiness.

All resources