hey thx for the fast answer,
I just set up a vm to thest the scenario now anyway. If you dont mind I would like to add a nother question. Is it possible to assign the static ip directly to the guest by adding some kind of rule or virtual device (dont mean to configure the virtual nic in the quest) ? So that Im just able to connect to the host by the guest and never bypass this setup? I hope I could explain what I try to do here 
basically just the guest sould be seen from the outsideworld not compromising the host to the outsideworld in any way (well beside the ssh tunnel that is initiated from the guest to the host)
regards
Markus