How iMessage Distributes Security to Block “Phantom Devices”
It turns out you can’t add devices to an iCloud account without triggering an alert because that analysis happens on your device, and doesn’t rely (totally) on a push notification from the server. Apple put the security logic in each device, even though the system still needs a central authority. Basically, they designed the system to not trust them.
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Once in place that will make it impossible to place a ‘tap’ using a phantom device without at least someone in the conversation receiving an alert. The way the current system works, you also cannot add a phantom recipient because your own devices keep checking for new recipients on your account.
I hope he can get Apple to talk about iMessage backups.
