Scheduled Internet Access And Steam

Hello,


On the Windows8 PC of my son, I expected the BDIS2013 parental control would filter internet access according to the time schedule.


During the "no-internet hours", it doesn't block Steam.exe which works on line gaming.


But I want to apply the time schedule to this internet access also...


How to do it ?


(do I need to understand which port is open ?)


or would it be possible that in Game mode, the rules be bypassed ?


Thanks for any help .


Ulysse.