Let’s say, I sit down in a mall, open my laptop and connect to a secured mobile hotspot. Then I do it again next week after a reboot. What information would a nearby shop or a passive malicious hacker be able to find about my device? Does my device send out identifying information before joining, like a MAC address? Is this persistent, or randomized?
I intentionally haven’t specified a distro, so if something only applies to some network managers, give some details.
Bonus points: what about Android phones?


I have no idea about Linux but on GrapheneOS the MAC address is randomized with each connection.The phone appears to be a different device each time.
This is actually an Android feature. iOS, too. It’ll give a random MAC or device MAC depending on what you want.
My MDM at work for Android-based handhelds I’ve configured to device MAC so I can geofence devices and keep track of them. If an employee connects to the employee network (which has to be configured by IT) we set it up with with device only MAC so we can add that device to the allowed list. Apple warns “it enables tracking” but if they ask I tell them in public it might be configured that way but we don’t care nor monitor that closely. If someone shares out the WiFi password by digging through settings, it wouldn’t matter as it’s not allowed.
Anyway, just thought I’d share both mainstream OSes do this now for a few years now.
Is this why my GOS phone does not connect back to my home wifi every time i leave and come back?
Mine connects if I don’t turn off WiFi in the phone settings. Not sure why yours isn’t.
probably bc im stupid and didnt realize I have set it to turn wifi off automatically if it stays disconnected from any router for 10min
Forgetting something doesn’t make you stupid.
very kind of you, thank you :)
I hope there’s a whitelist of SSIDs for this. I wouldn’t want my home router to register a new device each time I come back home
It’s a native Android feature since ~9 IIRC. Well, if the ROM maintainer didn’t decide to disable it for whatever reason :(
You can toggle it off for specific networks.