Valid question.
You would use active directory unless you have constituents that have to use it from outside your network. IFD allows people to access it from the internet instead of being inside your network. Like sales people out in the field or customers
that need access for some reason. Or if people are working from home without VPN access.
Your choices accomplish a deployment that can be accessed from outside the network are to use VPN or IFD.
So, if people don't need access from outside your domain, you wouldn't use it, you would just use Active directory auth.
Jamie Miley
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