________|________
|  ADSL router  |
|  192.168.1.1  |
|_______________|             _______________
   |        |                 | pfsense box |
   |        |_______________> |_____________|
   |           192.168.1.5            |
   |                                  | <---------DHCP from pfsense
   |<---DHCP from dsl router   _______|_________
___|______________             | Test computer |
| Home computers |             |  192.168.3.x  |
|  and laptops   |             |_______________|
|  192.168.1.x   |
|________________|