I have tripped on this old thread, and notice that it was unanswered.
Did you check the articles that we created on the Knowledge Base in the meantime?
https://success.outsystems.com/Support/Enterprise_Customers/Maintenance_and_Operations/Set_up_a_VPN_to_your_PaaS/01_What_is_a_VPN_(Virtual_Private_Network) and the links at the bottom of the page under 'More information'.
Does it address your questions?
Thank you for the reply but at the time, i asked directly to a colegue of yours and he answered me, although the new information you have pointed out clarifies what i was asking.