I’m at Eurocrypt 2025 this week.
We’re in a famcy hotel. We have NFC cards which unlock our rooms. The elevators in the lobby are summoned using the room card: you tap your card on the reader, and select a destination floor from a little menu. You don’t get to ask for any floor: it only offers a few common areas (the restaurant, the swimming pool, etc.) and the floor with yor room. This certainly makes the menu less cluttered; it also means it’s hard to wander around on floors other than the one with your own room. That’s good, right?
Continue reading Restricted room keys considered harmful.
