Tech Notes: Cidr/address Aggregation/summarization/subnetting

Let Start this blog explaining some concepts.
If you are studying for Cisco Certified Network Associate(CCNA) this will help you a lot.

People do confuse all this terns and also sometimes thinks that for example route summarization is equal to CIDR and that kind of thing so i decide to explain all of them.

Lets first look at the subnetting

This is something which the address mask is extended into the host space to address multiple data links under one major network address

Now looking in the other perspective a subnet address may be though of a as a summarization of a group of sub-subnets and also a major network address may be though of a summarization of a group of subnet address
What i mean is that for example if i got
a major netowrk 192.168.1.0/24
we can subnet it to

192.168.1.0/25
192.168.1.128/25

This would be 2 subnets of a major network of 192.168.1.0/24

But i could take the

192.168.1.0/25 and subnet it eeven more that part to

192.168.1.0/26
192.168.1.64/26

this would be sub-subnets of the subnet 192.168.1.0/26

I could summery this
192.168.1.0/26
192.168.1.64/26
to
192.168.1.0/25 which will be the thing i said above "a subnet address may be though of a as a summarization of a group of sub-subnets"

and i could summery thi
192.168.1.0/25
192.168.1.128/25
to 192.168.1.0/24 which is major network address that was summarized from a group of subnet address

Now what is summarizing?
Well summarization is reducing the lengh mask but without breaking the class limit of the major network. So what do i mean with this?
Well when you summarazing a Class C you will be just able to summarize till the /24 lets say if you got many /26s then when you summarazing you will be able to reduce the mask legh of the group of the /26 to something smaller than it but BIGGER than /24
for example
192.168.1.0/26
192.168.1.64/26
192.168.1.128/26
192.168.1.192/26

you can summarize that to 192.168.1.0/24

Now lets see Address aggregation(known also as supernetting)
Address aggregation takes the summarization a step furtehr by breaking the class limits of the major network addresses.
What do i mean with this?
for example if i had
192.168.0.0/24
192.168.1.0/24
192.168.2.0/24
192.168.3.0/24

I wouldnt be able to summarize that because i would be breaking the class limits....so what i can do is doing address aggretation and conver that to

192.168.0.0/22
So An aggregate address represents a numerically contigous group os networks address

Lets look at CIDR(classless interdomain Routing)
This is something that uses Address aggregation to resolve the problem of th exponential growth of the internet... all the Class B address were being used while the class C address werent soo used....
CIDR aggretares of class C addresses are allocated by the IANA to various worldwide address assignment authorities such as APNIC in asia ARIN in north america and RIPE in europe
The address assignment authorities in turn to divide their portion among the regional internet ISPs. When an organization applies for an aip address and requires addressing for a fewer than 32 subnets and 4096 host, it will be given a contigous group of class C address Called a CIDR BLOCK

So in this way the internet routers of individual organizations might advertise a single summary addres to their ISP.
The idea of this is summarazing addresses in a region in a single region address
Just to give you all an example of how this is distributed
Multi-regional 192.0.0.0 - 193.255.255.255
Europe 194.0.0.0 - 195.255.255.255
Others 196.0.0.0 - 197.255.255.255
North America 198.0.0.0 - 199.255.255.255
Central/South
America 200.0.0.0 - 201.255.255.255
Pacific Rim 202.0.0.0 - 203.255.255.255
Others 204.0.0.0 - 205.255.255.255
Others 206.0.0.0 - 207.255.255.255

So in conclusion
1-Summarizing is not equal to suppernetting... the both reduce the network mask lenght but ones breaks the class limit of the major network(supernetting) and the other doesnt(summarization) in other words summarization is to the right of the major network boundary while supernetting is to the left of the major boundary.
2-CIDR is not equal to summarization..... CIDR use address aggregation and CIDR is a solution to the exponential growth of the internet....