What does a network see when GrapheneOS connects?

ubersecure

If I connect my phone to a wireless access point, what information about the device and OS will they have access to?

Will they know it is a Google pixel phone connecting? Will they know it is running GrapheneOS?

How about if GrapheneOS is used on a network with SIM card? Same question about what the network provider can see.

raccoondad

ubersecure SIM has nothing to do with wireless access points, you can nmap it yourself, not much information. The MAC is also randomized

de0u

ubersecure If I connect my phone to a wireless access point, what information about the device and OS will they have access to?

Will they know it is a Google pixel phone connecting? Will they know it is running GrapheneOS?

https://grapheneos.org/usage#wifi-privacy
https://grapheneos.org/faq#default-connections

ubersecure

raccoondad

It was 2 separate questions, btw: 1) what can a WAP see about the phone when using wifi? 2) What can the network carrier see when using a SIM?

raccoondad

ubersecure What can the network carrier see when using a SIM?

Well, your IMEI number is tied to your phones model

ubersecure

de0u Exactly what I was looking for, at least as far as wifi.

I haven't had a chance yet to read how to disable default connections to GOS server. That would give away that the wifi is connected to a Graphene device, if an adversary were monitoring the wifi access point.

telemetry83

You should use an always-on VPN if you want to minimize the fingerprintable network traffic of the device. If an always-on VPN is not used, a network operator will be able to see DNS requests and TLS metadata for various GrapheneOS connections (releases.grapheneos.org for OS updates, apps.grapheneos.org for app updates, etc.). If the VPN is used, the network operator will see a VPN connection instead of many more unique, individual connections.

A cellular connection will reveal all of the same network traffic described above by de0u. If a VPN is used with a cellular connection, there are similar benefits to hiding the individual network connections. Additionally, your phone's IMEI is revealed to the carrier, which uniquely identifies your phone. The IMEI reveals the device model of the phone.

Cellular connectivity is inherently more invasive, so you'll never be able to fully hide your device from a cellular operator.

de0u

telemetry83 You should use an always-on VPN if you want to minimize the fingerprintable network traffic of the device.

Well... "always", except when it won't work. Over time more and more services are collecting lists of VPN endpoints and refusing some services to people connecting via a VPN. I don't know if the original poster is running into that, or whether the issue is a mismatch between the SIM number and the number being presented for verification.