在Android中，MAC地址是否随时间而变化

Question

Hello I want to get the MAC address of the android device so there is two ways either use WiFi or BlueTooth adapter for this.

Does this MAC address changes over the time when you turn on/off WiFi or BlueTooth or restart your device or factory reset. Any idea ?

Answer 1

MAC address is unique to each piece of hardware. They won't change. First few characters of the MAC address contains manufacturer information.

ps Except for those MAC addresses generated by simulator / VM, etc.

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UPDATE

Since Android 5.x, iOS 8+ and Windows 10+, MAC Address is generated and randomized each time Wi-Fi is turned on to protect user's privacy. Some operating systems even have different MAC address for each connected network.

Answer 2

Not entirely true Raptor. Android WILL generate a MAC address every time WiFi is activated if it doesn't have one. Here's how to tell (and how I fixed it on my Chinese tablet)

1. Root the device.
2. Open file "/data/nvram/APCFG/APRDEB/WIFI" with a hex editor.
3. if bytes 4 thru 9 are 0 then Android will generate a MAC address on-the-fly.

To FIX (hard-code) a MAC address, edit the "WIFI" file above and type a (any) MAC address into those byte locations (in hex notation, as you see it). Save the file. Reboot / restart WIFI and see setting. You should see your new address. And Android will now recognise your new address and won't generate a new one every time.

I did then to persist MAC filtering in my router, else the kids keep abusing my bandwidth by adding new i-devices.

Hope this helps

Answer 3

Android蓝牙MAC地址永远不会改变。