Let's say you want to set a static DHCP ip from your router. The only way to do so (from the router, I'm not talking from the phone), is by assigning an IP to a MAC address.

If the address is randomised per connection, affecting a static DHCP ip would be impossible.

Another thing a router often has is some sort of dhcp memory. It remembers the ip it gave to a certain MAC address for some time, then when the device connects back, it assigns the same IP it had before.

So if the ip changes each time either the MAC address changes each time (not sure it's default), or the router has no memory.

[–] example@reddthat.com 2 points 1 year ago (1 children)

for a device without inbound connectors and no ip based lan firewall rules, which applies to most phones, random per connection macs seem like a pretty good default for privacy.

some networks doing "unusual" things like hotel wifi limiting you to few devices (implemented by mac counting) may be thrown off though.

[–] jasondj@ttrpg.network 1 points 1 year ago (1 children)

I’ve run samba servers from my phones in the past (android, at least) which was nice for a “portable file server” when out and about.

[–] example@reddthat.com 2 points 1 year ago

I didn't say there were no use cases for this, but the average phone user will not need it. someone using samba on their phone would likely be capable of switching the network config to not randomize every time.

[–] Fosheze@lemmy.world 1 points 1 year ago* (last edited 1 year ago)

That's the point though. The address is randomized per connection specifically so the device can't be identified. It's to prevent tracking, blocking, or assigning, anything based on mac address without the device owners knowledge. Every time your phone connects the network has to treat it like a new device. If it was randomized per network that would defeat the point.

I personally can't think of any reason you would need a static IP on your phone but if you did then you should know enough to know how to turn off the randomized mac address. You can even change the setting per network so if you need a static ip at home then you just set your phone to use a static mac address on your home network and continue using a randomized one on every other network.