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Comment by colechristensen | Hacker News Reader

The metadata of who and where I am can't be encrypted away, unfortunately, it's available on the physical layer and obviously unavoidably a target of hacks.

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Your assumption is that a phone must present a permanent identifier to the network on the physical layer but I don't think that is true. You could have temporary identifiers instead. If you have multiple concurrent ones and stagger their renewals, and proxy all traffic over tor then it seems like goal would be accomplished.

You just explained the TMSI - something that was used since GSM networks in the early 90s

Good guess, but tmsi is to protect you from eavesdroppers, not from the mobile tower.

Well, you're invited to join research on network ... because it's impossible to hide your ID from your access network. Tor and similar can hide your ID in transport, but that's no option in RAN.

Well, the operator has to be able to link that temporary physical layer ID to some permanent billing ID, otherwise they will refuse your connection to their network.

I can see two ways around it. If you have a free data/calls/texts, you could use a zero knowledge proof of having a free-data secret. If you have pay-as-you-go you could spend tokens each of which are unique and anonymous.

Edit: I think the first approach may not work, as the secret could be duplicated..

That's something which requires cooperation from the operator, and they have zero interest in it at best, and more likely a strong negative interest on allowing anonymous devices on their phone network, in some countries even a legal prohibition to do so.

Both informations are abstract identifiers and are decoded in a database to 'real' values only, PHY doesn't care about your decrypted ID. If the operator keeps that database closed, a reasonable privacy of who and where can be done.

> If the operator keeps that database closed

Serious question, how much would you stake on that happening?

Serious answer: I have seen operators taking this serious. It's also a european trend not to blindly accept law enforcement requests to open data anymore.

For US companies: read something on the recent twitter example.

No, you have not understood. I'm not asking your opinion about seriousness.

I'm asking how much. So far you've shown a willingness to stake absolutely nothing, which is fair. Is that your response?

If not, how much?

i still don't understand. Should i put a bet (like €50), i can find an operator that closes such databases, or that you find an operator that doesn't?

I'm part of the mobile communication industry (while being in research) and part of my job is interacting with operators.

It's one thing to say "Oh yes, it's taken very seriously" when you have nothing riding on it.

It's another to pledge you will donate $100,000 to the FSF or whatever if data gets out in the next 5 years.

The first is worth nothing. The second claim is possible to have some weight.

The stuff gonna get hacked and we both know it. Why pretend otherwise?

Yeah, so I can blend into that huge crowd of people who both (a) sleep in the same bedroom as me and (b) work at the same office as me.

Great anonymity set you've got there.

So you have ID41323 and ID53242 over night (or at daytime) in the same location, how do you map this back to names?

It's not impossible, but you need data that exists (like house-to-name mapping) from databases outside of the reach of the operators.

And the location information in the network is only as precise as needed. Most of the time this is a cell area, so 100s of m2.

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