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IP Addressing and Subnetting: Practical Approach

Name: IP Addressing and Subnetting: Practical Approach
Rating: 4.7 (148 reviews)

IP Addresses and Subnetting Explained in a Simple Way!

Created byVipin Gupta

Last updated 1/2026

English

What you'll learn

What is IP address, IPv4 address format, public vs private IP addressess. What are A, B, C, D and E classes? What is CIDR? What is subnetting?
Why subnetting? How to subnet C, B and A class networks? How to divide class C, B and A networks into 2, 4, 8 and 16 subnets?
How to divide networks on the basis of number of hosts required per subnet?
Fixed Length Subnet Mask (FLSM). Variable Length Subnet Mask (VLSM). How to perform VLSM?

Course content

7 sections • 67 lectures • 5h 52m total length

What is Internet Protocol (IP) Address2:32
Just as in real life if want to communicate with someone, we need a phone, it could be landline/mobile. In addition we also need one number, which should be unique, then only we will be able to communicate.
Same way if we want 2 or more than 2 systems to communicate, we need unique numbers for the systems, that numbers are called Internet Protocol (IP) addresses. The IP addresses are of two types, IPv4 (32 bit) and IPv6 (128 bit). But here our focus will be on 32 bit IPv4.
How Many Different Number Systems are Available7:09
number system digits/letters min value max value decimal equivalent
binary (2) 0,1 00 11 3
octal (8) 0,1,2,3,4,5,6,7 00 77 63
decimal (10) 0,1,2,3,4,5,6,7,8,9 00 99 99
hexadecimal (16) 0,1,2,3,4,5,6,7,8,9 00 FF 255
A,B,C,D,E,F

We are more comfortable with decimal system.
Can we remember IP addresses in binary format.
What is Positional Value. What is Positional Value of Different Number Systems.3:30
What do you mean by positional value. What is the positional value of different number systems.
The positional value of “binary” system increases by a factor of “2”
The positional value of “octal” system increases by a factor of “8”.
The positional value of “decimal” system increases by a factor of “10”.
The positional value of “hexadecimal” system increases by a factor of “16”.
What is IP Address Range. What are the possible Minimum and Maximum Values.4:30
What is IP Address Range. What are the possible Minimum and Maximum Values.
32 bit address is divided into 4 octets (of 8 bits each). In each octet the “min” in binary format is all zeroes (00000000) and “max” is all ones (11111111).
In decimal, “min” is “0” and “max” is “255”. ie 4 octets can have min “0.0.0.0” and max “255.255.255.255” values. We can not assign any value less than “0.0.0.0” and any value more than “255.255.255.255”.
How to Find Valid and Invalid IP Addresses2:40
How to find out which IP address is valid and which one is not valid.
How to Find Which Part is Network and Which Part is Host5:32
IP 172.24.1.10 is a valid address since it falls between range. Now this IP address has got 2 parts. One is network part, other is host part. Which part is “network no” and which part is “host no” will be decided by “subnet mask”.
You can simply compare our IP addresses with our phone number which contains “city code” and “phone no” portion. For particular “city”, “code” will be same.
The mask can be of many types but mostly we are comfortable with
255.255.255.0
255.255.0.0.
255.0.0.0
How to find network part and host part.
Find Out Whether Systems are in Networking or Not5:06
If the network portion is same for systems, the systems will be in networking.
If the network portion is different for both systems, the systems will not be in networking. In this case no matter what mask we are going to set, the network portion will not be the same. so to make these 2 systems communicate we will need “router”.
What is CIDR (Classless Inter Domain Routing)2:11
What is CIDR (Classless Inter Domain Routing). How it is useful.
IP Addressing Fundamental Quiz

Unicast, Multicast and Broadcast Introduction3:20
What is the meaning of unicast, multicast and broadcast.
How to Find Valid Hosts, Network and Broadcast Address8:43
How to Find Valid Hosts, Network and Broadcast Addresses
How to Find Valid Hosts, Network and Broadcast Address Demo4:02
How to Find Valid Hosts, Network and Broadcast Address Demo
What do you mean by Public and Private Addresses.7:47
Why we always find that most of time in colleges, organizations, your systems, the IP addresses always start with “172”, “192” or “10”. Even in our examples, we are using these. Why we are not using other ranges.
This has to do with the concept of public and private addresses. Anybody can use private addresses. These addresses are free but internet routers are configured to block these addresses. On the other hand to use public (also called real addresses) address, you have to pay for it.
Web sites require public addresses.
What are different IP Classes (A, B, C, D and E Classes)12:14
How to View IP Address on Different Platforms5:40
Learn to view ip addresses on Windows, Linux, and Cisco routers using ipconfig, ip addr show, and ifconfig, and find website ip addresses with nslookup or ping.
What is Gateway or Router. When to use Gateway/Router.11:14
Learn the difference between gateway and router, assign first valid addresses across three networks, and see how a three-interface router enables inter-lab communication via a routing table.
(Optional) What is Gateway/Router Demo 18:49
Explore gateway and router concepts with a practical packet tracer demo, linking labs across 172.24.0.0, 192.168.0.0, and 10.0.0.0 networks, testing connectivity via ping and traceroute.
(Optional) What is Gateway/Router Demo 22:08
Use simulation mode to show how switches broadcast and routers route traffic between networks; pinging from PC1 to PC2 demonstrates gateway-enabled cross-network communication.
Working with IP addresses quiz

What is Subnetting. Why we need it.7:37
Subnetting divides large networks into smaller parts to reduce IP address wastage, comparing fixed length (FLSM) and variable length (VLSM) masks across A, B, and C class examples.
What is the Criteria For Subnetting3:17
Identify subnetting criteria by specifying either the number of subnets or the hosts per subnet, applied to class c addresses with two addresses reserved.

How to subnet Class C Network7:26
Explore class C subnetting with the 192.168.11.0 example, borrowing host bits to create subnets and determine usable hosts per subnet.
Understand Detailed Way of Creating Subnets14:35
Learn how to create subnets in a class c network using fixed-length subnet masks, selecting subnet bits, computing subnet addresses and valid hosts with detailed and shortcut methods.
Create 2 Subnets Using Detailed Method10:00
Create 2 Subnets Using Shortcut5:14
Explore a shortcut method to create two subnets, determine valid hosts and broadcast addresses, and apply a /25 subnet mask with 192.168.11.0/25 and 192.168.11.128/25 in a packet tracer demo.
Graphical View of 2 Subnets in Class C Network2:01
Visualize two equal subnets of a class c network using a fixed length subnet mask, showing 192.168.11.0/25 and 192.168.11.128, with 128 hosts each (126 usable) in a pie-chart view.
(Optional) Create 2 Subnets Demo10:01
Demonstrates creating two subnets on a class c network using /25 masks (192.168.11.0/25 and 192.168.11.128/25) with gateways 192.168.11.1 and 192.168.11.129, and verifies connectivity via ping in packet tracer.
Create 4 Subnets Using Detailed Method8:01
Shows how to create four subnets from a class C address using two subnet bits and six host bits, yielding /26 networks with 62 usable hosts.
Create 4 Subnets Using Shortcut4:24
Use the shortcut method on 192.168.11.0 /24 to create four subnets with /26 masks: 192.168.11.0, .64, .128, and .192, each with 62 usable hosts.
Graphical View of 4 Subnets in Class C Network1:42
Visualize a Class C network divided into four subnets with a fixed length subnet mask, 192.168.11.0/24 split into 192.168.11.0, 192.168.11.64, 192.168.11.128, 192.168.11.192 with a /26 mask, 64 hosts per subnet.
(Optional) Create 4 Subnets Demo9:31
Need 28 Hosts Per Subnet (Detailed Method)6:09
Calculate 28 hosts per subnet by using five host bits for 32 addresses and three subnet bits for eight subnets, yielding 192.168.11.0/27 networks with valid hosts 1–30 per subnet.
Need 28 Host Per Subnet (Shortcut)4:07
Use the shortcut subnetting method to support 28 hosts per subnet in a class c network, allocating 5 host bits and 3 subnet bits for eight subnets.
Graphical View of 8 Subnets in Class C Network1:30
Visualize eight equal subnets in a class C network with a pie chart, showing 256 hosts divided into 32-host subnets such as 192.168.11.0 and .224, illustrating fixed line subnet masking.
Create 16 Subnets Using Shortcut4:51
Use the shortcut method to create 16 subnets with four host bits, starting at 192.168.11.0, using a block size of 16 and noting broadcasts and valid host ranges.
Graphical View of 16 Subnets in Class C Network1:31
Class C Subnet/Host Bits Reference Table3:41
Class C Subnetting Summary4:41
Class C Subnetting Quiz

How to Subnet Class B Network5:30
Explore Class B subnetting using fixed length subnet masks to create 2, 4, 8, or more subnets from a /16 network, calculating hosts per subnet, valid hosts, and subnet ranges.
Understand Detailed Way of Creating Subnets7:12
Create 2 Subnets Using Detailed Method6:35
Create 2 Subnets Using Shortcut4:15
Use the shortcut method to create two subnets by using one host bit as a subnet bit, leaving 15 host bits. Networks: 172.24.0.0 and 172.24.128.0, with broadcasts 172.24.127.255 and 172.24.255.255.
Graphical View of 2 Subnets in Class B Network1:40
(Optional) Create 2 Subnets Demo8:47
Demonstrates class B subnetting to create two subnets, 172.24.0.0/17 and 172.24.128.0/17, using 255.255.128.0, testing with ping and Packet Tracer validation.
Create 4 Subnets Using Detailed Method5:18
Create 4 Subnets Using Shortcut3:51
Create four subnets using the shortcut method by two subnet bits and fourteen host bits, yielding about 14000 hosts per subnet.
Graphical View of 4 Subnets in Class B Network1:20
(Optional) Create 4 Subnets Demo8:42
Create four subnets from a class B network using a /18 mask, yielding 172.24.0.0, 172.24.64.0, 172.24.128.0, and 172.24.192.0, with show ip route and ping validations in packet tracer.
Need 8,000 Host Per Subnet (Shortcut)4:26
Graphical View of 8 Subnets in Class B Network1:48
Explore a graphical view of eight subnets in a class B network, dividing 172.24.0.0/16 into eight equal parts with a 16 plus 3 subnet mask, yielding 8190 hosts per subnet.
Class B Subnet/Host Bit Reference Table2:10
Class B Subnetting Quiz

How to Subnet Class A Network4:06
Explore class a subnetting on 10.0.0.0/8 with fixed length masks, using 1–4 host bits as subnet bits to create 2,4,8,16 subnets and millions of hosts per subnet.
Understand Detailed Way of Creating Subnets5:12
Create 2 Subnets Using Shortcut4:00
Graphical View of 2 Subnets in Class A Network1:14
Visualize a class A network split into two equal subnets, each with about eight million hosts, using a /9 mask for 10.0.0.0/9 and 10.128.0.0/9.
(Optional) Create 2 Subnets Demo6:21
Demonstrates two-subnet A class subnetting using 10.0.0.0/9 and 10.128.0.0/9 with 255.128.0.0, routing addresses 10.0.0.1 and 10.128.0.1, and basic connectivity checks.
Create 4 Subnets Using Shortcut3:25
Graphical View of 4 Subnets in Class A Network1:09
Explore a graphical view of creating four subnets in a class A network, using two subnet bits to yield a /10 CIDR mask and fixed-length subnets: 10.0.0.0, 10.64.0.0, 10.128.0.0, 10.192.0.0.
(Optional) Create 4 Subnets Demo5:03
Create 8 Subnets Using Shortcut3:59
this lecture demonstrates creating eight subnets in the 10.0.0.0/8 network using three subnet bits, yielding a /11 mask and about 2 million hosts per subnet, with examples like 10.0.0.0/11.
Graphical View of 8 Subnets in Class A Network1:04
Class A Subnet/Host Bits Reference Table2:37
Examine the class a subnet/host bits reference table, showing subnet counts from bits and host counts from bits; two million hosts require 21 host bits.
Class A Subnetting Quiz

VLSM Introduction5:52
Apply a variable length subnet mask to the 192.168.11.0 class C network by turning host bits into subnet bits to meet varying host requirements, using reference tables.
VLSM Case 110:53
Explore how to apply VLSM (variable length subnet masking) to a 192.168.11.0/24 network by allocating subnets for 120, 60, 28, and 12 hosts, deriving /25, /26, /27, and /28 masks.
Graphical View of VLSM Case 14:31
See the graphical view of a variable length subnet mask (VLSM). Divide 192.168.11.0 into subnets for 120, 60, 28, and 12 hosts using masks 25, 26, 27, and 28.
(Optional) VLSM Case 1 Demo7:45
Demonstrate vlsm by subnetting a class c network to meet 120, 60, 28, and 12 host needs using /25, /26, /27, and /28 masks, with practical routing and verification.
VLSM Case 27:07
Graphical View of VLSM Case 23:35
(Optional) VLSM Case 2 Demo5:16
Demonstrates VLSM case 2 subnetting for subnets with 50, 24, and 12 hosts, configuring networks 192.168.11.0/26, 192.168.64.0/26, 192.168.11.128/27, and 192.168.11.160/28, and verifying reachability.
VLSM quiz

Requirements

None

Description

If we want to construct 100 storey building, foundation should be very strong. Similarly, If you want to enter into networking field, fundamentals of IP Addressing and Subnetting should be crystal clear to you. This course is designed to make your IP Addressing and Subnetting fundamentals very strong.

In real life, if we want to communicate with someone, we need a phone, it could be landline or mobile. In addition we also need one number, which should be unique, then only we will be able to communicate. Same way if we want 2 or more than 2 systems to communicate, we need unique numbers for the systems, these numbers are called IP addresses. The IP addresses are of two types, IPv4 (32 bit) and IPv6 (128 bit). But In this course, our focus will be on 32 bit IPv4.

IP Addressing and Subnetting is the main ingredient of networking. Understanding and mastering it is going to pay rich dividends to you.

We are going to cover:

* What is IP Address

* IP Address Format

* IP Address Classes

* What is Gateway/Router

* Public/Private IP Address

* What is Subnetting

* Criteria For Creating Subnets

* Fixed Length Subnet Mask (FLSM)

* Variable Length Subnet Mask (VLSM)

* FLSM vs VLSM

* Why Subnetting

* How to Subnet C Class Network

* How to Subnet B Class Network

* How to Subnet A Class Network

* How to Perform VLSM

* Class A, B, C Subnetting Demo

In real life, to deal with certain things, we have to sometimes use carrot and stick policy. In this course, we are going to follow the same policy. Please do not get afraid. For me, Carrot (means Practicals) and Stick (means Theory). This course includes both theory and practicals.

Lots of material has been provided with this course for your reference. For properly understanding routing and subnetting, We have also created labs on FLSM, VLSM using Packet Tracer and provided lab files along with the course. The course includes lots of examples on Class C, Class B and Class A subnetting. Two methods of creating subnets has been covered. One detailed method and other shortcut method of subnetting has been covered. Customized diagrams and labs has been created to understand IP addressing and subnetting in simple and practical way.

Who this course is for:

For anybody who wants to learn IP addressing and Subnetting
For anybody who wants to enter into networking
Persons preparing for networking/security certifications
For anybody who wants to enter into DevOps

IP Addressing and Subnetting: Practical Approach

What you'll learn

Explore related topics

Course content

IP Addressing Fundamentals8 lectures • 33min

Working with IP Addresses9 lectures • 1hr 4min

What is Subnetting. Why we need it.2 lectures • 11min

How to Perform Class C Subnetting.17 lectures • 1hr 39min

How to Perform Class B Subnetting13 lectures • 1hr 2min

How to Perform Class A Subnetting11 lectures • 38min

What is Variable Length Subnet Mask (VLSM). How to Perform VLSM7 lectures • 45min

Requirements

Description

Who this course is for: