(((( )))))
                                  (  To the  )
                                  ( Internet )
                                   (((( )))))
                                       |
                                +------+-------+
                                |x.y.a.241/24  |
                                |Real host     |
                                |/router       |
                                |x.y.z.238/28  |
                                +------+-------+
                                       |net=x.y.z.224/28
                                       | 
    +----------------------------------+--------------------------------------+
    |                             x.y.z.225/28                                |
    |                   uml virtual firewall (router)                         |
    |       x.y.z.30/28          x.y.z.46/28            x.y.z.62/28    ...etc |
    +---------+---------------------+----------------------+------------------+
              |                     |                      |
              |net 16/28            |net 32/28             |net 48/28   ...etc
       -+-----+----+--       --+----+-------        --+----+-----+-   Fourteen
        |          |           |          |           |          |    such /28
        |          |           |          |           |          |    subnets.
   +---------+ +--------+ +--------+ +--------+ +--------+ +--------+ 10 used
   |x.y.z.17 | |x.y.z.18| |x.y.z.33| |x.y.z.34| |x.y.z.49| |x.y.z.50| in this
   |     /28 | |    /28 | |    /28 | |    /28 | |    /28 | |    /28 |  case
   +---------+ +--------+ +--------+ +--------+ +--------+ +--------+  study.
   subnet16_virtual_hosts subnet32_virtual_hosts subnet48_virtual_hosts  ...etc