71–80 of 122 posts
'add support for "5G only" and "4G or 5G only" modes in addition to our existing "4G only" mode' - https://grapheneos.org/releases#2025022700
I've always been wondering: Is there a SIM card configuration flag that allows telling the phone to never even attempt an attach using a given technology? This would allow leaking identifiers (at the cost of greatly reducing roaming coverage, at the moment), attaching to spoofed networks (for 2G, which does not have mutual authentication) etc.
if you pay the google tax for a pixel, you get a convenient 2G toggle. if you don't have an extra $400-900 and buy a cheaper android, you get to dial # #4636# # (hn screws asterisks, look it up) them go into phone info, select each sim radio and change the drop down (and hopefully you know all the standards by all names to make the right choice. hint 5G is NR there)
I know that setting, but I'm not entirely sure if that controls a preference or a mandatory cell config, and if it will prevent downgrades from the network side or not.
Some manufacturers and most custom ROMs also seem to offer that option without a dial code, but I haven't found any documentation about that feature yet to be sure it actually forces the modem configuration. I've found mentions online about this setting being changed without user interaction, so there seems to be a mechanism on some phones (carrier-branded ones maybe?) that alters this config.
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The phreaking [1] community was huge and becoming increasingly sophisticated long before mobile was even a thing. I think it's mostly that telecoms were traditionally discouraged from pursuing security. There's, at most, a minimal commercial incentive to it, and the government loves comms that can be easily spied on meaning you're going to get pushback from that side if you start aiming for security. The idea to star…
Don’t 2FA apps have the major downside that if you lose the specific mobile device you installed it on you’re SOL, unless you have backup codes that are too technical for most. SMS gets you more human support since you pay your carrier, I can walk into my nearest teleco branch with my ID if I lose my phone and change the SIM to another phone. So most of the time unless your SIM is hijacked it’s a good proxy for being…
If you don't want to lose access after losing your second factor, you don't want two factor authentication. Trying to make 2FA something it's not only muddies the waters and makes things annoyingly confusing.
I don't think "I know someone whose phone can't handle a 2MiB TOTP app" is a good reason not to offer real 2FA on a website. Sure, offer SMS codes for people who don't care much about security beyond ticking auditor boxes.
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That's sad for Apple, then. A poor decision on their part. Examples of Android phones that often support mmWave 5G: Samsung: Many Galaxy S and Z series models, including recent releases. Google: Pixel phones, especially the Pro models. OnePlus: Various 5G phones, including the 10 Pro, 10T, and Nord series. (etc) Apple should get their shit together.
It never worked unless you were walking on the street. Expensive too, I heard $20 per antenna. Millimeter is good for fixed antenna and delivering internet last mile to homes. Verizon bought into it millimeter while TMobile focused on mid bands, why T-Mobile is faster on average than Verizon. People use their phones indoors.
T-Mobile is also using mmwave and retaining it in urban cores, but returning a lot of the spectrum.
There's a LOT of spectrum work being done at the FCC right now... Or was...
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mmWave is going to be useful in places like stadiums or large arenas, though. It works wonders in these kinds of applications. WiMAX never really worked well at all.
Stadiums are pretty much the only place where mmWave in phones makes sense. For the other 99.99% of usage, it's an expensive power-hungry extra radio that doesn't work. mmWave 5G is mostly a sunk cost for Verizon, and largely irrelevant to everyone else.
Any place outside, in good weather, with high population density!
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Sprint deployed WiMAX (remember that?) fairly widely, lot of good that did them. mmWave is as dead as dead. The cellular Betamax. iPhone 16e (the everyman's iPhone) doesn't support it, and neither did the SE before it. VZW will be converting those base stations into birdhouses in 5-7 years.
mmWave is going to be useful in places like stadiums or large arenas, though. It works wonders in these kinds of applications. WiMAX never really worked well at all.
Neither did LTE (or VoLTE) work well at the start.
WiMAX didn't get the funding and backing primarily because it didn't integrate well with existing systems. Hilariously it fit the criteria as 4G before LTE did. I guess there was a strong vendor push to include LTE into 4G.
Criminal IMSI catchers are pretty much dead, but with the aid of carriers law enforcement can still use similar technology even with full standalone 5G networks. I don't know how often unauthorized IMSI catchers are used in the wild, but I doubt it's a relevant percentage of the total amount of IMSI catchers out there. Thanks to mmWave and beam forming, 5G allows operators to practically track you down to the exact c…
It should be feasible for an operator to issue a command to the (e)UICC (SIM) in the phone to fetch the current location from the modem and send it back via SMS. At least this was the case for a relatively long time.
Not that it _really_ matters because most people willfully give away their location information to Google anyways. There's a reason why Google has the best Wi-Fi AP -> Location database that they provide commercially. Send them a list of Wi-Fi BSSID's and their associated RSSI's and you'll get a fairly accurate location.
In comparison, using Cell ID's for geolocationing is finicky. In dense urban environments, you're likely looking at ~500 m radius of accuracy - at least based on the commercially available options.
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> depending on how willing the firmware of your modem is, the signal used to transfer GPS coordinates to the carrier for emergency response situations can also be triggered remotely by carrier hardware Do you know if (at least some) basebands actually limit network-side location requests to emergency call/text situations only?
All I know is that some don't. I don't know brands or if there are even common modems that are filtering for this. If you don't have a Faraday cage and cell site equipment, you're going to have a hard time verifying any of this. The modem is closed source, the SIM card is closed source, and various firmware blobs to make phones work are all closed source. I believe Qualcomm has debug interfaces on some chipsets, whic…
This is very unlikely to happen, primarily because certifying these modems is extremely expensive. I doubt any commercial vendor (e.g., a phone manufacturer) would commit the necessary resources to support them. Modern modems are also highly complex; they not only support various radio technologies but also incorporate numerous offloading mechanisms and a range of proprietary communication methods with telecom operators (e.g., VoLTE). Furthermore, the firmware must be carefully optimized for the hardware, so unless you have access to the complete package, this will likely remain confined to amateur circles.
> I honestly wouldn't be surprised if the standard was written to make this kind of surveillance possible and that any modem refusing to cooperate would be spec incompliant. You can read most of the 3GPP spec for free on sites like https://portal.3gpp.org/ but I don't have the time or interest to dig through the unreadable stream of abbreviations and industry terms to find out.
The standard is written to accommodate the most prevalent use cases. Given the ongoing efforts to improve security and address known vulnerabilities, I highly doubt it was written with bad intentions. However, that does not mean they will catch everything, nor does it guarantee that they will always prioritize stronger security over better usability - whether for network operators or end users.
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All I know is that some don't. I don't know brands or if there are even common modems that are filtering for this. If you don't have a Faraday cage and cell site equipment, you're going to have a hard time verifying any of this. The modem is closed source, the SIM card is closed source, and various firmware blobs to make phones work are all closed source. I believe Qualcomm has debug interfaces on some chipsets, whic…
Agreed – it's not really a personal concern I have (I have no illusions about the chances that none of the apps I grant location access to are selling it to the highest bidder), but I'm still curious. I can also imagine some legitimate use cases, such as pinging the location of somebody that had an accident and is possibly unable to call 911 themselves. And same here – I've read a few of the 3GPP specs, but they make…
They are technical standards designed to ensure interoperability (though not always successfully — cough VoLTE cough) rather than exhaustive guides on how to implement features. They have been developed over a long period of time and have become quite complicated to read, especially if you are not familiar with the specific nomenclature. However, with enough time and willpower you can make sense of them quite quickly.
PS. The software behind these standards is probably the most complex we have in the world. At least I am not aware of anything else that is as complicated.
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Verizon has actually deployed mmWave 5G fairly widely.
Sprint deployed WiMAX (remember that?) fairly widely, lot of good that did them. mmWave is as dead as dead. The cellular Betamax. iPhone 16e (the everyman's iPhone) doesn't support it, and neither did the SE before it. VZW will be converting those base stations into birdhouses in 5-7 years.
Nokia is also currently rolling out Europe’s first 5G standalone mmWave Radio Access Network in Italy. More to the point though, it could be integral in how we deal with NTN - particularly LEO D2C provisioning
https://filtronic.com/news-events/white-papers/time-to-step-...
https://mmtron.com/mmwave-leo-satellites-coming-over-the-hor...