Networking Contd
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Subnets
- consider the following scenario where a network of 2000 devices has to be created, so lets find the possible ip ranges for private network
- Lets define the CIDR Notation and Subnet mask
cidr: 192.168.0.0/21
sm: 11111111.11111111.11111000.00000000 - In this network we have 4 blocks and each block requires 500 devices
host id bits: 2^n ~= 500
host id bits = 9
network id bits = 32-9 = 23 - Lets create subnets from the overall network 192.168.0.0/21
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</ul>
<h1>overall network</h1>
cidr: 192.168.0.0/21
sm: 11111111.11111111.11111000.00000000
overall sm: 11111111.11111111.11111000.00000000
block sm: 11111111.11111111.11111110.00000000
<hr />
<pre><code> 11111111.11111111.11111xx0.00000000
</code></pre>
block 1 : 11000000.10101000.00000000.00000000 = 192.168.0.0/23
block 2 : 11000000.10101000.00000010.00000000 = 192.168.2.0/23
block 3 : 11000000.10101000.00000100.00000000 = 192.168.4.0/23
block 4 : 11000000.10101000.00000110.00000000 = 192.168.6.0/23
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* Lets create 8 subnets for the following requirement
* Lets find out network cidr - consider the following scenario where a network of 2000 devices has to be created, so lets find the possible ip ranges for private network
devices = 8000
2^n ~ = 8000
number of host bits = 13
network id bits = 32-13 = 19
network cidr => x.x.x.x/19 => 172.16.0.0/19
network sm: 11111111.11111111.11100000.00000000
each floor requires 1000 devices
2^n ~ = 1000
host id bits = 10
network id bits = 32-10 = 22
network sm: 11111111.11111111.11100000.00000000
block sm : 11111111.11111111.11111100.00000000
------------------------------------------------
11111111.11111111.111xxx00.00000000
xxx => 000, 001, 010, 011, 100, 101, 110, 111
ip: 10101100.00010000.00000000.00000000
f1: 10101100.00010000.00000000.00000000 = 172.16.0.0/22
f2: 10101100.00010000.00000100.00000000 = 172.16.4.0/22
f3: 10101100.00010000.00001000.00000000 = 172.16.8.0/22
f4: = 172.16.12.0/22
f5: = 172.16.16.0/22
f6: = 172.16.20.0/22
f7: = 172.16.24.0/22
f8: = 172.16.28.0/22
- We need to create a network for 2 lakh devices we have two datacenters and each datacenter in this network will have 1 lakh devices.
overall network => 200000
host bits => 18
network id bits => 32-18 = 14
overall network cidr: 10.0.0.0/14
network sm: 11111111.11111100.00000000.00000000
each subnet => 100000
host bits => 17
network id bits => 32-17 = 15
network sm: 11111111.11111100.00000000.00000000
subnet sm : 11111111.11111110.00000000.00000000
------------------------------------------------
11111111.111111x0.00000000.00000000
network: 00001010.00000000.00000000.00000000 = 10.0.0.0/14
subnet1: 00001010.00000000.00000000.00000000 = 10.0.0.0/15
subnet2: 00001010.00000010.00000000.00000000 = 10.2.0.0/15
