iOS 14 Per-Network MAC Addresses

With per-network MAC addresses in iOS 14, will there be user-facing controls to turn this on or off on a network-by-network basis?

Some networks may use DHCP reservations or MAC Access Controls for example and need an unchanging MAC, while for other networks privacy may be the strongly preferred mode for the user.

Also, how are the MAC addresses generated? Is a server involved? MAC addresses will change daily for each device-network pairing and need to be unpredictable to network observers, but can't be the same as other devices' current set of MAC addresses.
Up vote post of g0b Down vote post of g0b
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The introduction to the feature is mentioned in the "Build trust through better privacy" video (https://developer.apple.com/videos/play/wwdc2020/10676/).

Key points :
  • Users are always in control - users can control enablement of the feature at any time for each network.

  • Addresses are generated randomly for every network

  • Addresses are not linked to your identity

  • Addresses are updated for all networks daily by the device, NO server is involved in address generation. Since addresses are generated randomly, it is very unlikely that two devices on the same network will generate the same address.

  • A new MAC will be used whenever a new address has been generated and the device re-joins the network

  • Users can see which MACs are generated for each network in the Wi-Fi scan list, even before joining the network

Networks that use MAC-based access inherently track devices. Privacy on tracking networks can be controlled using the temporary address so that participation with the tracking network is also temporary.


I have follow up questions:
  • Does randomization follow the IEEE scheme (2nd from the last bit of the first octet as 1)?

  • Is randomization enabled by default?

  • Is daily randomization enabled by default?