From the link: "iOS devices can also detect an AirTag that isn’t with its owner, and notify the user if an unknown AirTag is seen to be traveling with them from place to place over time."
That's cool and all, but how do they handle a trainload of people all going the same direction sitting near each other? I mean public transportation is still a thing.
They mentioned this exact scenario on their website[1]
> Of course, if you happen to be with a friend who has an AirTag, or on a train with a whole bunch of people with AirTag, don’t worry. These alerts are triggered only when an AirTag is separated from its owner.
You still can tell if someone is tracking you. I'm not aware that Apple allows in any way for an apple watch or iphone to monitor the location without making the holder aware.
I don’t disagree, but this is not any comfort to the children of tech savvy parents. They’ll be tracked and they’ll know they’re being tracked and they won’t have recourse. AirTags are kind of irrelevant here.
I don't know what Apple is doing behind the scenes here, but if I were Apple, I would generate much more "signal" from "this AirTag is traveling with this one person that is not its owner" than from "this AirTag is traveling with forty people that are not its owner".
And maybe this tag is generating a stronger signal than any other and is registered to me. Apple is all about the user experience so I assume they have a solution, just curious what it is.
So after the owner accidentally leaves it on the train, someone will be notified to look for whatever item was so important that it needed to be tracked.
> Of course, if you happen to be with a friend who has an AirTag, or on a train with a whole bunch of people with AirTag, don’t worry. These alerts are triggered only when an AirTag is separated from its owner.
It only triggers if it’s not with the owner but is with someone else. I wonder what happens if you put your luggage on a train and sit down elsewhere on the train. Would it recognize that it is still, generally speaking, with the owner?
I wonder how they allow a device to tell that the same AirTag is being seen repeatedly without allowing malicious third-parties to do the same?
I thought the system was designed in such a way that the data is meaningless to anyone but the owner of the tag, so that third-parties can't learn anything from said data.
The iOS device keeps seeing a random AirTag in close proximity. Even as the ID rotates, it's still about 2m away, and continues to be 2m away as you move. It doesn't know who it belongs to, but it's probably the same physical device, because it keeps going to wherever you're going.
That's a different scenario than the evil store owner who wants to track their customers. In that case, it's just a random procession of tags roaming about the store. A tag arriving at the store on repeated days has nothing to indicate that it's the same one.
So if it's being used as a malicious tracker (hidden in someone's car or purse), then the constant proximity is a clue. But if someone is trying to guess which tag belongs to a specific person, they can't unless they maintain constant contact with that tag over a long timeline. At that point, they can just see you :)
how long is the suffix? I can't see it being effective for both anti-stalking (ie. someone placing a tag on you without your consent) and anti-tracking (ie. shops/malls using your tag to follow you around).
I don't know the answer to that, but thinking about it generally: If the suffix was just a single hex digit, it would work to detect a persistent tag. After, say 5 key rotations, if the last digit is still "E", then it's highly likely that the tag that's constantly in range is the same physical thing.
Meanwhile, if you're trying to use these things to track visitors to your store, you're only getting 16 bins of people. My "E" tag will be the same as 50 other people who've visited last week with the same "E" suffix.
I'm having a hard time finding the actual whitepaper on this. Hopefully someone links it in this thread.
Unfortunately, the spec is currently only available to partners in the MFi program. That is probably where parameters like the one you are asking about are defined: https://developer.apple.com/find-my/. I’m sure there will be a paper published that reverse engineers the spec once these devices are out in the wild.
Finally, the static part of the broadcast doesn’t need to be permanently static. It simply needs to rotate at a period that’s longer than the rest of the public key.
>even if users don’t have an iOS device, an AirTag separated from its owner for an extended period of time will play a sound when moved to draw attention to it.
You realize these devices already exist and for much cheaper right? In fact you can buy or make your own with gps and a sim card too. This technology isn't new at all. Even this exact product isn't new, you can already do this with Tile. The big difference is that AirTags are more secure.
> And even if users don’t have an iOS device, an AirTag separated from its owner for an extended period of time will play a sound when moved to draw attention to it.
I'm not sure how that solves anything. I'm worried about situations like people tracking others by placing the AirTag on their person. If they gotten close to them once, they can probably do it more times too, to retrigger the inactivity period.
> And even if users don’t have an iOS device, an AirTag separated from its owner for an extended period of time will play a sound when moved to draw attention to it.
