[HN Gopher] PGPP - a new type of service that gives you private ...
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PGPP - a new type of service that gives you private mobile
connectivity
Author : jacooper
Score : 56 points
Date : 2022-09-06 13:02 UTC (9 hours ago)
(HTM) web link (invisv.com)
(TXT) w3m dump (invisv.com)
| adg001 wrote:
| IMSI is not the only identifier available to mobile networks and
| attackers alike. Does PGPP provide IMEI randomization? What stops
| the mobile networks from tracking you using the IMEI associated
| to the ephemeral IMSIs?
|
| Answer found in the linked paper:
|
| """
|
| For many devices, the IMEI can be changed through soft- ware,
| often without root access. We envision a PGPP MVNO would allow
| for subscribers to present their unchanged de- vice IMEI, giving
| the PGPP operator the opportunity to check against a EIR to
| verify the phone has not been reported as stolen. At that point,
| the IMEI could be reprogrammed to a single value, similar to our
| changes to the SUPI. Additionally, PGPP users can readily switch
| SIMs to different handsets (IMEIs) at-will. Note that different
| jurisdictions have differ- ent rules about whether, how, and by
| whom an IMEI can be changed, so only in some cases IMEI changes
| require cooper- ation with the MVNO.
|
| ...
|
| A PGPP-based carrier is data-only, with voice and messaging
| provided by third parties.
|
| """
|
| So, the next question is: if voice is provided by third parties
| (i.e., relies on the actual IMSI/IMEI), what stops the mobile
| operator from correlating the presence of the IMSI/IMEI to the
| ephemeral IMSIs/IMEIs, so as to infer the real network identity
| behind the randomised IDs?
| richardwhiuk wrote:
| I suspect they assume that voice would be provided by something
| OTT - e.g. Signal.
| kornhole wrote:
| But you still need to make and receive regular OTA calls and
| SMS at times. This is where VOIP is needed such as voip.ms,
| Twilio, Google voice.. Voip.ms with Linphone app and SMS app
| called VOIP.MS on android have worked well for me. I
| occasionally and rarely use a burner sim but do everything
| over WIFI with VPN.
| barathr wrote:
| Not sure how this ended up on the front page again, but FWIW we
| discuss a lot of the privacy goals of the system here:
| https://invisv.com/articles/pgpp-more.html
|
| There are fundamental tradeoffs here, so it's good for users to
| know what they're interested in protecting against, compare
| against the security model that the system provides, and
| determine if it works for them and their needs.
| edf13 wrote:
| So you can get 30 IMSI switches per month... that doesn't sound
| like anywhere near enough for me.
|
| Also - what happens if you're on a low traffic cell site and make
| the change. Suddenly a new IMSI appears on that tower (With a big
| jump from it's last location). I'm pretty sure I could track
| someone with this service.
| richardwhiuk wrote:
| I can't imagine any MNO would accept this as an MVNO.
| 310260 wrote:
| They don't necessarily have to. It can be an always-roaming
| service. Similar to what JT and Truephone offer.
| lxgr wrote:
| Roaming still requires a contractual agreement between home
| and visited network.
| prvit wrote:
| The branding is pretty revealing. They're calling this "PGPP"
| because they want to sell to drug dealers.
|
| Various "secured" encrypted phones have been sold as "PGP phones"
| for years now regardless of underlying the technology having
| anything to do with PGP.
| ziddoap wrote:
| > _They're calling this "PGPP" because they want to sell to
| drug dealers._
|
| Can you explain how this follows? It sounds like you're
| claiming that the only people who have an interest in privacy
| are drug dealers? Which would be a pretty ridiculous take, if
| that's what you're implying.
| prvit wrote:
| Drug dealers make up like 90+% of the market for expensive
| cryptophones.
|
| There's been a bunch of companies selling "PGP phones"
| specifically to drug dealers. Many of these have been shut
| down by LE. If you look, you'll find that most of them
| unsurprisingly maintain physical storefronts in drug dealing
| hotspots like Marbella.
|
| The idea isn't that only drug dealers care about privacy,
| it's that they're the people with enough disposable cash and
| few enough brain cells to buy this stuff.
| notjulianjaynes wrote:
| I thought it t was a pun on 3GPP.
| prvit wrote:
| That's only credible if we're to believe that they know
| literally nothing about the market they're entering.
| notjulianjaynes wrote:
| I think, especially in the wake of EFF's Fog Data broker
| investigation, the idea that drug dealers are the only
| market for a tracking resistant mobile device is untrue.
| (Although I guess I'd buy that drug dealers are more
| receptive than the general public to something branded as
| "PGP."
|
| But I'm one of those strawmen on the other side of this
| debate (a journalist) and such a product is appealing to
| me. If it's not appealing to the general public that is IMO
| a lack of education on the topic.
|
| That said, I have not reviewed how this is particular thing
| is supposed to work, and my assumption is that it is An0m
| v2 until proven otherwise. Additionally, doesn't Signal
| require a phone number to sign up? If this service provides
| no phone number how does that work?
| prvit wrote:
| General public isn't going to spend $1k+/yr on a SIM card
| to avoid data brokers.
|
| Yeah, you might sell to a few rich nerds from HN. But for
| each of those you'll get tens of drug dealers and other
| organised crime.
| Quarrel wrote:
| While I think you're probably correct, re the branding they're
| after, it does dovel tail nicely with 3GPP.
|
| https://en.wikipedia.org/wiki/3GPP
| barathr wrote:
| We named it entirely as an homage to the original PGP. This was
| literally an academic research project we did, with the exact
| same name, for _years_ before we made it into a service.
| RunSet wrote:
| > We named it entirely as an homage to the original PGP.
|
| Are you affiliated with any of the authors or developers of
| "the original PGP"? To be precise, Phil Zimmermann, PGP Inc,
| Network Associates, PGP Corp, or Broadcom Inc?
| herodotus wrote:
| Perhaps someone can explain this. If Alice calls Bob, her carrier
| has to be able to locate Bob to make his phone ring. Therefore,
| Bob can always be tracked. I do not see how this can be overcome.
| Seems to me that this service is a perpetual motion machine.
| im3w1l wrote:
| There are many ways to solve this. The simplest one is that Bob
| owns a trusted server that always knows where he is. He uses a
| few proxies in series to connect to this server. When Alice
| wants to call Bob she contacts his server.
| traceroute66 wrote:
| > We envision a PGPP MVNO ....
|
| Ok, that's cute. I hope you know how hard it is to setup an MVNO
| these days.
|
| It also kind of rules out that little thing called roaming, which
| is kinda popular these days.
| 310260 wrote:
| MVNOs rule out roaming? Since when?
| apienx wrote:
| Damning conclusions in TFP. https://arxiv.org/pdf/2009.09035.pdf
|
| "In addition, law enforcement has long demanded backdoor access
| to private user devices and user data [61]. We do not believe
| that users of PGPP, in its current form, would be capable of
| withstanding targeted legal or extra-legal attacks by nation-
| state organizations (e.g., the FBI or NSA)"
|
| Randomizing the IMSI is great and all, but it only protects
| against >20-year old interception techniques (e.g. Stingrays).
| Nothing to see here.
| dane-pgp wrote:
| > In addition, law enforcement has long demanded backdoor
| access to private user devices and user data
|
| Law enforcement has long demanded all sorts of things, but the
| presence of such a demand doesn't mean that they have the
| backdoors which that statement insinuates. If anything, the
| fact that law enforcement is having to publicly beg for private
| access suggests that they don't already have it (unless you
| believe that is a bluff).
|
| > capable of withstanding targeted legal or extra-legal attacks
| by nation-state organizations
|
| If your threat model includes "nation states are going to break
| their own laws to attack me" then you're not safe even if you
| never use a phone. In fact, you're not safe even if you never
| commit a crime.
| [deleted]
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(page generated 2022-09-06 23:02 UTC)