Subnet basics
=============

Public domain
********************************************************************************


       IP   : 192.168.100.57
    Netmask : 255.255.255.240

      /                    /                                   /
     |  57  = 00111001    |    NetID   :  00110000  = 48      |    NetID   : 192.168.100.48
    <                    <                                   <
     |  240 = 11110000    |  Broadcast :  00111111  = 63      |  Broadcast : 192.168.100.63
      \                    \                                   \

      /
     | 256 - 240 = 16
     | 57  \ 16  = 3
     | 3   * 16  = 48  (NetID)
     | 48  + 16  - 1  =  63 (Broadcast)
      \


      | IP  | Mask | Prefix |
    --|-----|------|--------|--
      | 256 | 0    |  /24   |
      | 128 | 128  |  /25   |
      | 64  | 192  |  /26   |
      | 32  | 224  |  /27   |
      | 16  | 240  |  /28   |
      | 8   | 248  |  /29   |
      | 4   | 252  |  /30   |

********************************************************************************
_BY: Pejman Moghadam_  
_TAG: subnet_  
_DATE: 2011-03-07 19:10:56_