[modem]
  |
[router - 192.168.123.254]
  |
[switch]
  |
<eth0>
[softrouter - 192.168.1.1]
<eth1>
  |
[switch]
  |
[laptop host eth0: DHCP(192.168.1.<100-254>) guest eth0: DHCP(192.168.1.<100-254>)]