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Memorise it..class C subnets

Here are the possible Class C subnets:

  |  Bits   |        Mask        |  CIDR  |  Subnets |  Hosts  |   
  |    0    |  255.255.255.0     |   /24  |     1    |   254   | 
  |    1    |  255.255.255.128   |   /25  |     2    |   126   | 
  |    2    |  255.255.255.192   |   /26  |     4    |    62   | 
  |    3    |  255.255.255.224   |   /27  |     8    |    30   | 
  |    4    |  255.255.255.240   |   /28  |    16    |    14   | 
  |    5    |  255.255.255.248   |   /29  |    32    |     6   | 
  |    6    |  255.255.255.252   |   /30  |    64    |     2   |

* Classless Inter-Domain Routing notation

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