I think i'm not explaining myself right, this would have to be done *without* installing anything on the machine.
For instance, i have some scripts that pull all kinds of information from machines without installing anything on them (just need access and rights, exactly what i want to check). This would be something similar, but i don't know how, if possible, to integrate these on your NAC.
Installing anything on the machines creates me another problem i have right now with the current inventory software...
I'm not a programmer, but i'm always open to new challenges and i'm sure i can contribute with great ideas for this issue if pointed in the right direction