To further protect your privacy, your iPhone, iPad, iPod touch or Apple Watch can use a different MAC address with each Wi-Fi network.
To further protect your privacy, your iPhone, iPad, iPod touch or Apple Watch can use a different MAC address with each Wi-Fi network.support.apple.com
The motives are good and if you use public wifi hotspots then having different MAC per connection makes sense to stop tracking. But, and there is a but, what happens if you use MAC addresses to determine access or profiles on your home network?
As is apparent, MAC addresses can't be relied on as an infallible method to distinguish one device from another but for [young] kids devices it's a viable option. It also helps if you know this change has happened and you don't spend ages trying to figure out why you can no longer access Media Server from your iPhone.
The three impacted services that occur to me are:
- DHCP services: client IP reservations are done on MAC address. Either...
- In each iPhone/iPad switch off the Private Address option for your home WiFi connection.
- Update DHCP client reservations with each iPhone/iPad's new private MAC address (brief testing on/off seems to retain the same private MAC).
- DSM's Media Server: in DMA Compatibility is the ability to filter access to selected devices, based on MAC address. Useful to stop access to shared media if it's not appropriate for everyone (there's Video Station/Plex that can keep kids away from your horror collection!).
- SRM's Safe Access: to assign devices to non-default profiles is based on their MAC addresses as an identifier. If you want different profiles to set permit Internet times and content access then you have to know the MAC addresses, or make the default profiles very restrictive and then manage devices that can access less restricted profiles.