Subnet (Bit count to dotted decimal) Description

Subnet( bit count to dotted decimal)

How to convert a subnet which is in bit count into a dotted decimal ?

Suppose we have a subnet value which is 27 and can be written also as 255.255.255.224 in dotted value. So to convert it, here are the following steps. 

We know that each bit value in a subnet is an 8 bit value and is equal to 255 so if we took out 8 bit each from 27 we will have 24 bits with the 3 bits remaining which will be equal to

255.255.255 

now the remaining 3 bits left in the bit count can be calculated which is shown below 

First Write the table  as shown below 

128        64        32        16        8        4        2        1 

Now start filling the remaining three bits from the left side

like this  

128        64        32        16        8        4        2        1  

 1         1       1      0      0      0      0     0   

  

Now add the numbers where the remaining three bits are filled which is 128 + 64 + 32 which is equal to 224 so this how we get the remaining value now the conversion complete and the subnet is

255.255.255.224 

Here are some other questions with solutions for you to understand and practice 

1)  9

Sol

Now first fill the address with 8 bit value we get the remaining bit which is 1 

Now convert the remaining bit using the table 

128        64        32        16        8        4        2        1 

 1            0          0          0         0        0        0        0

Now after converting the remaining bits we get the subnet value which is

255.128.0.0 

2) 15

Sol

Now first fill the address with 8 bit value we get the remaining bit which is 7

Now convert the remaining bit using the table 

128        64        32        16        8        4        2        1 

 1            1          1          1         1        1        1        0

Now after converting the remaining bits we get the subnet value which is

255.254.0.0 

3) 12

Sol

Now first fill the address with 8 bit value we get the remaining bit which is 4

now convert the remaining bit using the table 

128        64        32        16        8        4        2        1 

 1            1          1          1         0        0        0       0

Now after converting the remaining bits we get the subnet value which is

255.240.0.0  

4) 18
Sol

Now first fill the address with 8 bit value we get the remaining bit which is 2

now the convert the remaining bit using the table 

128        64        32        16        8        4        2        1 

 1            1          0          0         0        0        0        0

Now after converting the remaining bits we get the subnet value which is

255.255.192.0