Yes, the tram is outside security. When you arrive in T1, you'll need to walk a bit to get to the "domestic" side of T1, outside of which the station for the tram is located. You need to have a boarding pass or printout of your itinerary for your connection - they will NOT let you board the tram without one of these documents.

The tram departs only every 15 mins, so plan for a bit of time. Once in T2, the walking is less.