Subnetting

[DaivaPrasad3147]

Hii, 

192.168.1.0/24 

How to divide this Network into 20 Networks?

Kindly please explain

[Martin L]

/29 gives you 20.  why? actually /29 gives you 32 networks; too much but /28 gives you 16, which is not enough. this is taken from 2^4=16 but 2^5=32.   Basically, you looking for x power of 2 that gives you n (number of networks).  what number when 2 is raised by it, gives you number of networks.  so, 5. this means you must borrow 5 bits from /24 for subnetting to get at least 20 networks; reaming number of bits is used for hosts.  24 + 5 =29, hence /29 is the answer

Regards, ML
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[balaji.bandi]

if you looking /24 into 20 subnets usable (is this what you looking ?)

All 16 of the Possible /28 Networks for 192.168.1.*

All 32 of the Possible /29 Networks for 192.168.1.*

use the below tool nice once for learning.

https://www.calculator.net/ip-subnet-calculator.html?cclass=any&csubnet=28&cip=192.168.1.0&ctype=ipv4&printit=0&x=66&y=9

[Tyson Joachims]

1. Convert the subnet mask from decimal to binary

255.255.255.0 = 11111111.11111111.11111111.00000000

2. The 1's are the network bits and the 0's are the host bits. We will be borrowing from the host bits to get more networks. Look at the bit values from left to right looking for a value of 20 or greater (since you are looking for 20 networks).

3. From left to right, replace all the 0's with 1's until you reach the value of "32"

4. Convert from binary to decimal

11111111.11111111.11111111.11111000 = 255.255.255.240

Answer: A subnet mask of 255.255.255.240 will subdivide a subnet mask of 255.255.255.0 into 32 distinct subnets which satisfies the requirement of subnetting into 20 networks. We can check our work:

The first network would be 192.168.1.0/29 and the 32nd network would be 192.168.1.224/29