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VLSM Short-cut

I hope this post will guide you to calculate VLSM very shortly. Also you don’t have to remember binary for every number except subnet mask.

I take an IP address, for example: 192.168.100.40 /27


1


Step 1 : Subnet Mask

3


Step 2 : Network Address and Broadcast Address

Fill first 3 octets with IP Address.

4


5


6


Now the first number of the block is Network Address and Last number of block is Broadcast Address.

7


Step 3 : Valid IP Range

9


Step 4 : Number of Hosts

10

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Comments

  1. AnonymousOctober 3, 2013 at 8:07 AM

    Very nice and easy explanation.
    Thank you

    ReplyDelete
  2. AnonymousMarch 21, 2014 at 2:10 PM

    Thank you so much . That was informative .

    ReplyDelete
  3. AnonymousJune 9, 2014 at 9:09 PM

    thx a lot for the tutorial

    ReplyDelete
  4. DebashishJuly 21, 2014 at 2:14 PM

    Excellent !! Thanks a LOT for the easy explanation !

    ReplyDelete
  5. UnknownOctober 27, 2019 at 7:12 PM

    Good simple

    ReplyDelete
  6. ARUNNovember 1, 2019 at 10:50 AM

    Could you post fr class a.. B also

    ReplyDelete

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