IP Addressing : A quick start for you
Today i will talk about the IP addressing. It is one of the basic topic in networking field and people should know it anyhow. Some of you are already equipped with the IP addressing and some of you are at the initial stage to learn the things.
If you want to start your career in Networking or as an Network Engineer, IP addressing should be the key topic to know on your tips. Without IP addressing you will not able to understand the networks and how it works, summaries , how VLSM works, Subnetting and supernetting concepts and so on.
IP addressing is the recoganisation of the device on the network whether it is LAN or WAN. LAN is called your local area network and WAN is Wide area network. The concept of LAN and WAN is already covered in another post earlier. You can check that posts if you want to understand the concept of LAN and WAN.
Coming back to IP addressing, IP means, Internet Protocol addressing. It is unique and can be assigned to Computers, Laptops, Printers, Switches, Routers and so on that depends whatever equipments are there in your network.
IP addressing are of two versions:
- IP version 4 : 32 Bits
- IP version 6 : 128 Bits
IP Version 4 :
Let's talk about IP version 4 first. As i discussed in above statement, IP version 4 is 32 bits addressing space and it is like
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IPV4 addressing Format |
So the above diagram shows you the format of IPv4 which clears the fact of 32 bits. Now there are two kinds of Classes in the IPv4 addressing and they are as :
- Unicast IP class addressing
- Multicast IP class addressing
Unicast IP class addressing:
We have 3 classes under Unicast IP addressing and these classes are Class A, Class B and Class C. In these classes we further have two kinds of IP addresses and they are Private IP addresses or Public IP addresses. Private IP addresses are the addresses which you can use in your private LAN network for the identification of the network devices while Public IP addresses is allocated by your Service provider so that you can uniquely identify onto the internet or Public platform.
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Fig 1.2 - Unicast IP address Class |
First let's talk about the Classes, we have 3 classes as i mentioned above. The range of the IP addresses in these classes are shown below.
- Class A: IP addressing range 0-127
- Class B : IP addressing range 128-191
- Class C: IP addressing range 192-223
To understand more on the classes range IP addresses, Lets take an example, I have an IP address of one of my end device 192.168.1.1. The IP address 192.168.1.1 falls under Class C.
Another Example, I have the IP address 172.16.10.1. Now tell me which class it belongs to ? I guess you got it right, It belongs to Class B IP address. Similarly if i have the IP address 10.10.10.1, this IP address belongs to Class A.
I knew you didn't noticed one thing, I used all the IP's which is Private IP's and can be used in your Local network while these classes have Public IP addresses as well. So first clarify about Public and Private IP addresses in these classes
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Fig 1.3- Private Unicast IP addresses |
Class A:
Private IP address: 10.0.0.0 to 10.255.255.255.255
Public IP address : All Class A IP addresses except the above mentioned private IP range.
Class B:
Private IP address : 172.16.0.0 till 172.16.255.255
Public IP address : All Class B IP addresses except the above mentioned private IP range.
Class C:
Private IP address : 192.168.0.0 till 192.168.255.255
Public IP address : All Class B IP addresses except the above mentioned private IP range.
Private IP address: 10.0.0.0 to 10.255.255.255.255
Public IP address : All Class A IP addresses except the above mentioned private IP range.
Class B:
Private IP address : 172.16.0.0 till 172.16.255.255
Public IP address : All Class B IP addresses except the above mentioned private IP range.
Class C:
Private IP address : 192.168.0.0 till 192.168.255.255
Public IP address : All Class B IP addresses except the above mentioned private IP range.
Multicast IP class addressing:
Now for the multicast address, there is another class in IPv4 addressing and that class is Class D. This Class D IP address ranges from 224.0.0.0 till 239.255.255.255. These IP addresses generally uses for multicast applications in the network. we will come up in details about the multicast IP addresses and the use cases on these soon in another post.
Hope you now clarify on Basic topic of the IP addressing. We will come up with the Subnetting in the IP addressing and also the information about the IPv6 addressing and how it differ from IPv4 and why we are in need of IPv6.