Not a bad idea. We are looking into this. One issue is that the vendors for these keyfobs are super fragmented -- even more so than Plug & Charge adoption.
Worth being aware that, as well as keyfobs being super fragmented, many are woefully insecure. Think "they just say their ID number when you put them in a reader field".
That means you can trivially clone them. Not hugely exciting for access to a (common) hallway in a large building. If cloning someone else's fob gets you free car charging, the incentive is there to clone them. Also, not all buildings will use unique fobs per "unit" (and you'd likely need to support per-resident/tenant fob uniqueness... And something for guests!) -- sometimes it's a single hardcoded value for the whole block or door zone that the fob opens...
You can, of course, build something proper using NFC (and a smartcard running a smartcard applet), which is effectively like your own custom mini "chip and PIN" EMV system -- you would have to design and implement the wire protocol to authenticate the card etc etc, and all the security design around that, but it could be done. That would at least let you have something more than simply shouting your tag ID number into the air like a super basic NFC tag (or RFID keyfob).
Our current plan is Plug & Charge (via ISO 15118 as well as a fallback to our NFC cable) and Tap to Pay as a backup in case you haven't set up a payment method on your vehicle.
g_p|2 years ago
That means you can trivially clone them. Not hugely exciting for access to a (common) hallway in a large building. If cloning someone else's fob gets you free car charging, the incentive is there to clone them. Also, not all buildings will use unique fobs per "unit" (and you'd likely need to support per-resident/tenant fob uniqueness... And something for guests!) -- sometimes it's a single hardcoded value for the whole block or door zone that the fob opens...
You can, of course, build something proper using NFC (and a smartcard running a smartcard applet), which is effectively like your own custom mini "chip and PIN" EMV system -- you would have to design and implement the wire protocol to authenticate the card etc etc, and all the security design around that, but it could be done. That would at least let you have something more than simply shouting your tag ID number into the air like a super basic NFC tag (or RFID keyfob).
ClumsyPilot|2 years ago
i have cloned keyfobs for like 5 building at a local laundry. Never met a fob they couldn't clone
Daneel_|2 years ago
I feel like no matter what you’ll need to accept credit card payments in these sort of shared environments.
akouri|2 years ago