Silent link for ~privacy outside home

Guidance0831

Hello there,

If one need internet access outside home for e2e messaging but only in rare case like protests or actions, do you think that silent link is a good option ? Airplane mode is activated all the time otherwise.
The threat model is not letting my carrier triangulate me in protests.

Can GOS spoof the IMEI when using a different esim ? I already have a KYC carrier that i used before and now only over VOIP for bank phone number verifications, contact sharing and stuff like that.
So silent link would be nice if I appear as a different phone to the cell tower when i'm using it, otherwise if i am still traceable with my IMEI by the operator it's less appealing.
Or is a prepaid sim a better idea since the IMEI depends on the sim slot i beleive ?

Thanks by advance for your ideas

NetRunner88

Guidance0831

There are two imei, one for physical slit, one for esim.
Changing imei is illegal in most (not all) countries worldwide.
Each sim/esim has its unique IMSI.

An obvious correlation can be established between imei/imsi. But these days basic law enforcement track IMSI not imei has it is irrelevant for them. They want to identify your number associated to your physical person..

If you fear something change phone and use a non kyc sim like silent you mentioned.

argante

NetRunner88 That's not enough. If your phone registers at night where you usually sleep, during the day at your usual work location, and additionally at places where you've paid with a credit card, then no KYC is needed to know it's you.

NetRunner88

argante
Yes and ? I didn't developed opsec
If you fight against alphabet-bois drop everything and go live in a forest or something

Guidance0831

Yeah you're right, the silent link e sim would be used only when needed in "sensitive" operations and disabled otherwise in addition to always being in airplane mode.
So for you using a KYC free e sim provider rather than my regular carrier does not improve confidentiality and is not harder to track when used only for like protests ?
I am also thinking of IMSI catchers that the police may deploy in these cases to get a list of all the people here.
I know that ideally i should just not take my phone but I sometime need it to share messages while being in the event .

thmf

Guidance0831 the problem with all that is it's very easy to make an innocent mistake even if you're extra careful. One tap in the wrong place on the screen while you're at home/school/work and your identifiers are already "there" (or at least somewhere).
Maybe consider having a separate cheap GrapheneOS phone (see here and here) with silent link that's always offline till you're at the protest? You'll need a procedure for that, e.g. come earlier, do full OS update, sync E2E prior messages, etc. Worst case even if you're detained it's quite unlikely "they" will get into your phone, or at least not immediately. They'll need to wait for a new or known working exploit to come out to get in (hence the need for a full OS update prior to the protest). There's no known working exploits against GrapheneOS in BFU or AFU state at this time, so you're very much safe against physical attacks on your device. And even if "they" won't give you your phone back once you're free to go you'll still have your usual device waiting for you at home.
Of course nothing beats not having a phone with you at all in the first place.

argante

Guidance0831 Read about meshcore (meshtastic is a bad solution, but is more well-known). You can also use Wi-Fi to build mesh connections using Briar. And watch these videos:

https://www.youtube.com/watch?v=vMJH-UJyENs
https://www.youtube.com/watch?v=x_5y1jIWPjc

argante

NetRunner88 Yes and ?

Geofence warrant.