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 defi

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/ 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. The protocol is in Ivan Kristic’s Black Hat 2019 talk: https://i.blackhat.com/USA-19/Thursday/us-19-Krstic-Behind-The-Scenes-Of-IOS-And-Mas-Security.pdf https://i.blackhat.com/USA-19/Thursday/us-19-Krstic-Behind-T... 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.