[HN Gopher] Ask HN: Is anyone working on an open hardware 3G/4G ...
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Ask HN: Is anyone working on an open hardware 3G/4G dongle?
I just saw this one https://unsigned.io/openmodem/ and was
wondering if someone was working on a open hardware 3g/4g usb
dongle ?
Author : marto1
Score : 143 points
Date : 2021-08-08 10:24 UTC (1 days ago)
| Dwolb wrote:
| Depends how open you mean. For a lot of hobbyists and
| integrators, this works:
|
| https://github.com/hologram-io/nova-hardware
|
| And run this on a Pi:
|
| https://github.com/hologram-io/hologram-python
|
| If you need something one layer deeper on the module or chipset
| level, there's not really a lot out there.
| marto1 wrote:
| That actually looks pretty cool. I'll check it out. Thanks!
| h2odragon wrote:
| Observer, not participant; but:
|
| It's my understanding that the FCC and equivalents make it almost
| impossible for there to be open hardware that connects to the
| phone network. And any cracks they haven't filled, Qualcomm has
| NDA'd the documentation for.
|
| see https://osmocom.org/projects
| netr0ute wrote:
| > the FCC and equivalents make it almost impossible for there
| to be open hardware that connects to the phone network
|
| How?
| nzmsv wrote:
| FCC has issued guidance for manufacturers to protect against
| modifications that would break FCC rules. The easiest way to
| do that is to have a closed-source baseband firmware.
|
| https://prplfoundation.org/fcc-open-source-router-
| software-i...
| randyrand wrote:
| Open hardware means that people can be their own
| manufacturer.
|
| There are lots of places that will make PCBs for you, and
| sell you the parts to solder together.
| rkangel wrote:
| It depends what you mean by 'closed-source'. Yes it's
| probably impossible to certify a radio baseband that anyone
| can hack on. It would be possible to manufacture a radio
| baseband for which all the source code was public and
| anyone could verify that that source code was running.
| R0b0t1 wrote:
| There is no legal requirement to close the baseband off.
| They tried to close off routers in the same way and got
| pushback.
| netr0ute wrote:
| Sometimes it's easier to ask for forgiveness than
| permission.
| trothamel wrote:
| Asking might come with a large fine if 911 service is
| interrupted.
| netr0ute wrote:
| A fine might actually be lower cost than losing freedom
| to binary blobs, so there's that.
| oneplane wrote:
| But most of the time Quallcomm, Broadcom and the others
| have an army of lawyers and an absurd amount of money to
| burn to ensure that your project, life and general
| existence is ruined, just to protect their bottom line.
| penagwin wrote:
| Something tells me you might have a difficult time
| convincing say Qualcomm with just that reasoning.
| netr0ute wrote:
| You could conceivably reverse-engineer the hardware if
| you got the support of places like MIT, and then it's
| fair game from there.
| userbinator wrote:
| The standards themselves are freely available (and extremely
| difficult to understand) --- just search for 3GPP --- but I
| think the main problem is spectrum licensing and transmitter
| approval.
| PaulHoule wrote:
| Don't the phone companies have a veto over what they let attach
| to their networks?
| netr0ute wrote:
| That has to do with IMEI, and with most baseband software,
| the IMEI can be whatever you want.
| macinjosh wrote:
| Thanks government!
| sumtechguy wrote:
| Also there are several other companies that have a lock on that
| thing.
|
| When I worked at QCOM at one point I had access to that the 3g
| versions. My boss had printed it out. It was about 2 inches
| thick single spaced double sided. Rumor was the 4g one was
| double that. Then there was the 'chipset'/serial interface
| about the same size.
|
| So _could_ you re-write one? Yeah (given the time for it).
| Never mind the legal tangle that bcom, qcom, marvel, whatever
| Motorola is these days, Huawei, ZTE, and others have built
| around it. That would just be the technical. Then getting it
| onto a real cell network would take a lot of work. You prob
| could make your own in a unlicensed band though if you stuck
| inside the power limits. Title I /II determine what people can
| and can not do with the US networks. Think the current thinking
| is physical connection you can do quite a bit, but radio it is
| locked down. But I could be wrong.
|
| Have to check that proj out. Looks cool!
| jeroenhd wrote:
| I'm no expert in this area, so I'm just going to ask: suppose
| you implement the entire 4G standard, but alter the used
| frequencies to a range you can legally transmit on (say, the
| 2.4GHz or 5.2GHz range), would the technology be different
| enough that it couldn't be adapted into a real 4g modem by
| changing the frequency range the device operates at? Is there
| some inherent technical challenge that makes the technology
| operate around 1600MHz but not around 2400MHz?
|
| LTE has some advantages over WiFi (i.e. the IoT features, the
| roaming features, the endpoint management features) so I can
| see a 2.4GHz LTE network being quite useful in some edge
| cases. With open technology, private LTE networks can
| probably serve quite nice business use cases.
| jaywalk wrote:
| You might want to take a look at the table on this
| Wikipedia page showing the frequency bands where LTE has
| been deployed:
| https://en.wikipedia.org/wiki/LTE_frequency_bands
|
| It already ranges from 450MHz to 5.2GHz.
| rkangel wrote:
| No, that is completely possible. I have worked on a project
| where we ran mostly standard LTE hardware in the ISM band
| (2.4 G) and it worked fine.
| zamadatix wrote:
| Not only is this possible there is actual spectrum
| dedicated to this kind of purpose https://en.wikipedia.org/
| wiki/Citizens_Broadband_Radio_Servi... though there are a
| lot of other rules around it (e.g. some slices can be
| allocated in a given region to a licensed user but not all
| of the slices in a region).
| sumtechguy wrote:
| The particular bands the cell providers run in were sold to
| them by the government (or bought from someone else who got
| them from the gov). If I remember correctly it was mostly
| the antennas lengths and what the tuner was set to for the
| chipsets (some being fixed, some being more SDR). Some
| bought those particular bands because they tend to
| penetrate buildings better than others.
|
| But yeah if you could keep inside the power levels, and
| stay in the unlicensed bands, and keep out of trouble with
| the patent courts you probably could make an LTE network. I
| would not be surprised if many of the chipsets already
| could do it. Power levels would be your biggest hurdle for
| something more than a test network.
| marcan_42 wrote:
| This is not only possible, it's already a thing with
| unmodified hardware. The 900 MHz band is a ham radio band
| in the US, but it's used for GSM in Europe. That means that
| you can quite legitimately set up a GSM base station in the
| US if you have a ham license, as long as you abide by ham
| radio regulations (which might require some hacks), e.g.
| you can't turn on encryption and you need to broadcast your
| callsign periodically. Then most multiband phones will
| connect to it thinking it's a European GSM network. I can't
| find it right now, but I watched a talk where someone
| described doing just that.
|
| 900MHz is also used for LTE in Europe, so I'm pretty sure
| you could do the same thing with 4G/LTE.
| pcdoodle wrote:
| One could be made with the pinephone modem. I believe its running
| a version of android and people are working on reverse
| engineering it right now. The chip is a little big for a dongle
| so you'd end up with something kinda like the OpenModem in your
| link there.
| jraph wrote:
| Some impressing work is indeed being done here on the PinePhone
| modem: https://github.com/Biktorgj/pinephone_modem_sdk/
| (firmware replacement, with a re implementation of many blobs
| and a mainline linux kernel - I tried and everything seems to
| work, however the sound is a bit low by default (this can be
| configured) and the modem is slow to boot)
| ksec wrote:
| Not exactly a dongle but something like this?
|
| https://bellard.org/lte/
| marto1 wrote:
| Ha! I actually read about this a few years ago, but this is an
| entire base station :-)
| skywal_l wrote:
| Him again!
| seltzered_ wrote:
| "Introduction to open source private LTE and 5G networks" might
| have some pointers: https://ubuntu.com/blog/introduction-to-open-
| source-private-...
|
| discussion: https://news.ycombinator.com/item?id=27946947
| rsync wrote:
| If the baseband and associate chipsets are isolated on the other
| side of a USB connection, why not use (any old dongle) and
| isolate it with some kind of USB "condom" with configurable
| "firewalling" ?
|
| In fact, I believe I have seen such devices for USB development -
| a configurable passthrough USB interface that would allow you to
| control what gets sent over the interface.
|
| That kind of a setup would be _much, much easier_ to develop and
| safeguard than developing a modem /baseband from the ground up
| ...
| trollied wrote:
| This was posted a little while ago, and might interest you:
| https://news.ycombinator.com/item?id=28051005
|
| https://blues.io/products/
| milesvp wrote:
| I thought that board looked interesting. Looks like a $50
| cellular board, includes 500MB of data over 10 years (though
| with missing fineprint according the the HN thread). Might not
| be a terrible board to design around. Though adding it to your
| BOM will make your final retail cost on the order of $450.
|
| Some creative googling got me this, for a different starting
| point. Looks like it might be a useful project writeup dealing
| with SDR and connecting to some cellular sources.
|
| https://www.blackhillsinfosec.com/intro-to-software-defined-...
|
| I'm not sure how common open SDR hardware is, though some forum
| threads seem to suggest the Hackrf schematics are here, and are
| meant to be replicated:
|
| https://github.com/mossmann/hackrf
|
| I think one of the big problems is ultimately going to be
| dealing with phone companies. I think that will ultimately
| stymie any open efforts in this space, since at the end of the
| day, you need someone to accept your cellular traffic.
| cookiengineer wrote:
| Might be only a bit related, but osmocomBB [1] is a quite
| complete project that implemented an open baseband library.
|
| It can be installed on a lot of old dumbphones and allows to
| create a base station and mobile station. Might help you to
| understand the inner workings of the network protocol quirks.
|
| Back then it was known to be _the_ project to easily build an
| IMSI catcher, so its scene got a lot of redteamers using it.
|
| There is also an ongoing effort to reverse engineer the usb modem
| of the pinephone, but afaik it's still a lot of work. [2]
|
| [1] https://osmocom.org/projects/baseband
|
| [2] https://github.com/Biktorgj/pinephone_modem_sdk
| 0xbadc0de5 wrote:
| The most mature (4G/5G) project would probably be
| https://github.com/srsran Couple it with a LimeSDR and you'd have
| a fully open HW/SW stack.
| teameat wrote:
| Just curious, what would the advantage of having an "Open 4G USB
| Dongle" be ? Why not just get a Ublox or similar module ? Even if
| it's open you still have to pay usage on the carrier's network.
| marto1 wrote:
| That's going to be a very long list, but of the top of my head:
|
| 1. Much easier repairs since all schematics are known in
| advance.
|
| 2. Price. A lot of the price of the modems comes from licensing
| fees as others have already noted.
|
| 3. Integration. Directly embedding the pcb into your project
| will be much, much easier.
|
| 4. Collaboration. Working together in projects that utilize 4G
| becomes easier too. Many use cases might get revealed without
| the original creators intending for them.
|
| 5. Security. "More eyeballs on a line of code make bugs run
| away" and all that jazz.
|
| Only disadvantage might be reverse engineer people might get
| bored not having enough things to RE :-)
| teameat wrote:
| Gotchya,
|
| Although a 4G module like a ublox is pretty easy to throw on
| a PCB, most of those things are just a couple chips inside so
| it just seems like there's not a lot of repairs other than
| just swap out the module. I've seem those modules in the $20
| range, seems like a lot of work to get around the licensing
| fees on a $20 module?
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(page generated 2021-08-09 23:02 UTC)