[HN Gopher] Building a private LoRa network (2017)
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Building a private LoRa network (2017)
Author : Tomte
Score : 197 points
Date : 2022-11-16 11:34 UTC (11 hours ago)
(HTM) web link (os.mbed.com)
(TXT) w3m dump (os.mbed.com)
| cozzyd wrote:
| We deployed a private LoRa (and also an LTE) network on the
| Greenland ice sheet for one of our experiments. We use LTE for
| data transfer and LoRAWAN for housekeeping / control (and leave
| it on during the winter when we have no solar power and are
| basically just monitoring our batteries). We are taking full
| advantage of our remote location and Greenland's nebulous ITU
| region to have them in almost the same band (using LTE band 8 and
| LoRa in the US ISM band).
|
| The most annoying part was porting LoRaMAC to the samd21, since
| getting the timing reliable was a bit of a pain. We used the
| sx1272 as our radio.
|
| We use a Chirpstack backend, which handles authentication and
| such and passes the unencrypted the LoRaWAN messages over mqtt,
| which we subscribe to, decode, and stick into a pgsql database on
| our server on the ice sheet. We then use log shipping replication
| to get a replica of the database to a server sitting in our lab
| where we are not bandwidth constrained for monitoring.
| ilyt wrote:
| What range and with what kind of antennas/power level you're
| getting?
|
| > and LoRa in the US ISM band
|
| that's 900MHz right ?
| cozzyd wrote:
| So far our farthest stations are about 5 km away from our
| base station. The RSSI is around -111 dB, this is using ~20
| dBm transmit power and 8 dBi omni antennas on both sides
| (plus of course a few dB of cable loss). Yes, this is in the
| 915 MHz band.
|
| We tested our LTE network out to about 9 km and it worked,
| and LoRa should have a better link budget. The frequency is
| roughly the same.
| snthd wrote:
| It's patented and proprietary, please don't use it.
|
| Alternatives: https://en.wikipedia.org/wiki/Low-power_wide-
| area_network#Pl...
| syedkarim wrote:
| Why should we not use something that is proprietary? Every
| transceiver IC in the world is proprietary.
| [deleted]
| furtiman wrote:
| While the LoRa radio modulation (phy) is licensed by Semtech,
| the MAC layer protocol - LoRaWAN is completely open and is free
| to be used, implemented and tinkered with. https://lora-
| alliance.org/
|
| Many implementations are also open-source, like The Things
| Stack from The Things Network. It can also be run locally.
|
| https://github.com/TheThingsNetwork/lorawan-stack
| generalizations wrote:
| I'd want the entire stack to be open and free. When Layer 1
| is closed and proprietary, I don't really care if I can build
| open source on top of it, in Layer 2.
| runjake wrote:
| Is this not the case with existing computers and phones? We
| build and run OSS on top of them.
| generalizations wrote:
| It is, and there is a lot of effort being expended to
| remediate that - there's a reason why some people use
| pre-2011 thinkpads. I think it would be pragmatic in new
| endeavors to do things right and correctly from the
| start, so that remediation isn't needed later.
| runjake wrote:
| There have been many commercial and crowdsourced attempts
| to do so, with variable levels of success.
|
| Do you buy or participate in those?
|
| I care, but not enough to leave my iPhone (more
| specifically: the functionality, usability, and
| reliability it provides) behind, at this point.
| anfractuosity wrote:
| Was Chirp Spread Spectrum developed prior to LoRa itself out
| of interest? I had a little look at
| https://en.wikipedia.org/wiki/Chirp_spread_spectrum but
| couldn't really tell.
|
| I was under the impression that other modulation schemes such
| as FSK etc. can also perform similarly to CSS in terms of
| data rate etc. and distance?
| khimaros wrote:
| any specific recommendation? it seems like all of these
| alternatives have tradeoffs and LoRa really does seem to tick
| more boxes than the others.
| snthd wrote:
| I don't, sorry.
|
| It's a few years since I researched it, and I didn't build
| anything.
| HideousKojima wrote:
| From that list of alternatives, which of the open ones have the
| widest adoption/support?
| delabay wrote:
| Now do the same for Helium!
| [deleted]
| b800h wrote:
| As this operates in the "Open Spectrum" I suspect it's very
| geographically constrained, as the spectrum is allocated
| differently from country to country. I would have to check but
| I'm not sure there's an equivalent in the UK, for instance, which
| you could operate without an amateur radio license.
|
| EDIT: Scratch that, looks like there's a frequency it can use in
| the UK:
|
| "Both LoRa(tm) and LoRaWAN(r) use the 868Mhz radio frequency that
| is license exempt in the UK. This doesn't mean you can use this
| frequency as you like. There is set a set of rules defined by EU
| ETSI EN300.220 (pdf) the most pertinent of which is the duty
| cycle that defines for how long a transmitter can transmit."
| gpvos wrote:
| Same as the article says to use in Europe. Probably an EU rule
| that carried over.
| [deleted]
| furtiman wrote:
| I'm from The Things Industries and The Things Network team.
| LoRaWAN standard specifies regional parameters, that is -
| specific ISM spectrum bands for every region where LoRaWAN is
| used. All of the regional parameters are supported by The
| Things Network and The Things Stack, you would only need to get
| hardware that has the radio of the frequency you need. It is
| specified in here
| (https://www.thethingsnetwork.org/docs/lorawan/frequencies-
| by...) and in LoRa Alliance standard https://lora-
| alliance.org/wp-content/uploads/2021/05/RP002-1...
| comboy wrote:
| Anybody played with Mikrotik KNOT LR8 kit? I like them but it's
| new and I want something reliable when I'm learning
| furtiman wrote:
| I can confirm it works well, Mikrotik have good experience in
| LoRa gateways and have been in the market for quite some years
| mactunes wrote:
| I recently got interested in installing a TTN gateway in my home
| and adding some temperature sensors.
|
| Having played with LoRa years ago my thought was that there
| should now be readily available and cheap sensors. But to my
| disappointment everything seems to be a bit pricey which really
| surprised me. I can get a Zigbee temp sensor for around 15 euros,
| but Lora sensors cost around double that. I am wondering as to
| why that is?
| SirMonkey wrote:
| This is pure speculation - I have no prove. I believe is also
| due to the target buyer: afaik the biggest adopters are
| municipalities and not general consumers.
| extra88 wrote:
| The market for Zigbee products is likely much larger so per-
| unit costs are lower.
|
| Also, it seems LoRa is proprietary and patent-encumbered while
| Zigbee is an open spec.
| ilyt wrote:
| Still need to pay up if you want to sell zigbee devices
|
| https://e2e.ti.com/support/wireless-connectivity/zigbee-
| thre...
|
| ...which is also the reason Zigbee is more pricy than random
| wifi enabled gadget
| Tijdreiziger wrote:
| Zigbee can't be _that_ expensive, since you can pick up
| IKEA TRADFRI Zigbee bulbs for around EUR6 a piece.
| bullen wrote:
| The problem with LoRa is that you can't (or atleast shouldn't)
| control the frequency from software.
|
| Which is exactly what you want. Also the frequency band is a bit
| too narrow and short ranged for real earth applications.
|
| LoRaWAN is terrible because you move into the overengineered and
| heavy IP stack... the other way is better: build your own "from
| scratch" network topology in software.
|
| Fossilization is only good _after_ you prooved the concept.
| rexreed wrote:
| I am fascinated by LoRa, but I understand it is primarily for low
| bandwidth applications that are optimized for high range, low
| power consumption. I'd imagine LoRA would be a good alternative
| to SMS but would it ever be an alternative for voice or higher
| bandwidth applications while still maintaining long range and low
| power?
| sifar wrote:
| Me too. I envision a pebble like smartwatch or an eink phone
| with Lora.
|
| Lora on 2.4 GHz can probably provide the higher bandwidth
| required for voice albeit at a lower range compared to the sub-
| GHz version. look up SX1280.
| superkuh wrote:
| No radio transmission that is above 30 MHz or so is really
| "high range". The modulation doesn't matter. The only thing
| that matters for range in non-ionospheric bouncing radio
| transmissions is the height above surrounding terrain of both
| ends of the link.
|
| SMS works because the cell phone companies pay the big bucks to
| their base stations up very high above surrounding terrain.
|
| There are transient exceptions like atmospheric gradients in
| water vapor density creating brief tropospheric ducts which VHF
| radio can bounce down but these are unreliable. And
| tropospheric scattering propagation requires very high powers
| and high gain antennas at both ends so it's not really feasible
| for people operating under FCC part 15 or even ham radio power
| restrictions (ie, <1500 watts).
| linsomniac wrote:
| If everyone having a phone in their pocket at all times has
| taught me anything, it's that people hate talking to each other
| over the phone... :-). LoRA/Meshtastic seems like a really
| interesting SMS transit.
| FL410 wrote:
| Nope, it's not meant for that. Think low-bandwidth, small
| transmissions with highly compact but valuable data (sensors,
| actuators, etc). Even with LoRa as-is, changing settings to
| optimize for bandwidth costs you real range.
| kkielhofner wrote:
| Exactly. Not LoRa but an example of what these modules and
| low bandwidth can do.
|
| Many years ago (pre-LoRa) I needed to integrate a garage door
| that was far out of Wifi range to my home automation system.
|
| At the time the way to go about this was (as best as I could
| tell) XBee. I was able to conjure together a 900 MHz XBee
| module in the garage that not only had (essentially) GPIO to
| activate a momentary relay to simulate a button push to
| control the door but also utilize an XBee feature called
| change detection that has an eventing/push system to transmit
| state changes from high to low on a pin. Combined with a
| magnetic door contact sensor and XBee + ESP 8266 + Arduino
| (platform for ESP 8266, not device) + MQTT on the Home
| Assistant side this thing has been running rock solid for a
| decade. I haven't had to work on it since.
|
| Whether I check the status of the door (via Home Assistant or
| the OLED display on the control unit inside) or open/close
| the door via the momentary switch inside (or Home Assistant)
| even though it's been 10 years at least once I week I remark
| at how amazing the entire contraption is.
|
| This stuff is really cool and maybe it's time to move this
| thing to LoRa!
| ilyt wrote:
| Probably not worth it, Zigbee is literally designed for use
| case like that, LoRa is designed for use cases where you'd
| have much wider geographical spread of sensors.
|
| But something like solar powered sensor somewhere farther
| away would be a good use case.
| moffkalast wrote:
| Speaking of costs, are the public gateways actually free to
| use or does one need something like a sim card to use them?
| What prevents people from spamming messages at rates that
| completely clog the network?
| SirMonkey wrote:
| If we are talking about the radio spectrum: Not much -
| other than the threat of the regulators showing up at your
| doorsteps after they found you with a van. If you are
| talking about the backbone so to say, it's not such a big
| Issue. The original packet-forwarder sends "json" over UDP.
| If you are using a packet-forwarder by one of the network
| operators, some of them are using MQTT (IP/TCP) as the
| transport.
|
| Some gateways let you filter by network_id, this will not
| stop someone from pulliting/disrupting the radio spectrum,
| but it will stop your gateway from relaying those packets
| to your network-server.
| rexreed wrote:
| What is the sweet spot in terms of bandwidth and packet size?
| ilyt wrote:
| https://www.thethingsnetwork.org/docs/lorawan/spreading-
| fact...
|
| There is none, there are only tradeoffs.
|
| You're basically directly trading off range for speed and
| power usage.
|
| Quicker chirps allow for both higher speed and lower power
| usage per byte transferred, but your range will be that
| much lower
| GekkePrutser wrote:
| LoRa isn't even a good alternative for SMS. The duty cycle, at
| least in Europe is too low to have a real-time conversation.
| rexreed wrote:
| By duty cycle are you referring to slow message latency and
| small packet size?
| GekkePrutser wrote:
| No, here in Europe a device on the LoRa band 868Mhz can
| only transmit 1% of the time by law.
|
| Because this also applies to base stations the throughput
| is highly constrained.
| furtiman wrote:
| LoRa is not a panacea, and of course any technology is best to
| what it is intended. With its ultra low power and data
| constraints LoRa is not aimed at high-bandwidth applications.
|
| The perfect application is IoT, where a lot of use cases like
| telemetry, agriculture, etc. require only small data packets
| transmitted with longer (tens of minutes / hours) intervals.
| m-p-3 wrote:
| Personally I'd see some use in regional and low bandwidth
| sensor data, like broadcasting weather station data.
| furtiman wrote:
| I made a similar guide and a walkthrough video about a year ago,
| where I cover setup of gateway and TTN, creating a firmware for a
| device locally, and a lot of other helpful steps and hardware
| options
|
| https://github.com/furtiman/5lic0-lorawan-basics
|
| https://www.youtube.com/watch?v=A3cZSTfxmb4
| prbs23 wrote:
| I somewhat recently blogged about my process of setting up a
| private LoRaWAN network as well.
|
| https://prbs23.com/blog/posts/getting-started-with-a-private...
|
| LoRaWAN is definitely an interesting mix of open source
| implementations and open specifications, and proprietary poorly
| documented hardware. Unfortunately I haven't had time lately to
| actually use my network for anything real.
| glonq wrote:
| I just finished two-year project to build a sensor data
| acquisition system that was based around private LoRaWAN
| networks. Our custom gateway was Chirpstack running on a little
| linux SBC connected to a RAK LoRa module.
|
| It took some effort to solve congestion and reliability when the
| network got busy.
| varispeed wrote:
| HackerNoods wrote:
| cpach wrote:
| Please don't create new accounts for the sole purpose of
| writing comments like this. It makes for neither good nor
| interesting discussions.
| HackerNoods wrote:
| m-p-3 wrote:
| You should read this
|
| https://news.ycombinator.com/newsguidelines.html
|
| > Eschew flamebait. Avoid generic tangents. Omit internet
| tropes.
|
| > Please don't use Hacker News for political or
| ideological battle. It tramples curiosity.
| sokoloff wrote:
| It's a relatively simple RF transmission protocol. We might as
| well try to ban FM radios from certain countries.
| gruturo wrote:
| You're not entirely wrong, but it's a very common radio
| technology, which anyone is free to use (even implement from
| scratch, with enough skills) with very few restrictions (which
| don't really affect state actors).
|
| You may as well ban screws, lenses, explosives, radio, rubber,
| chocolate and internal combustion engines with this line of
| reasoning. What will it achieve? Russia won't stop using them.
| actionfromafar wrote:
| Well, some Russian car factory stopped because they couldn't
| get screws. Also, they couldn't make their own screws,
| because the screw-making machine had wear parts which they
| couldn't get.
|
| Of course they won't stop using these common components
| altogether, but the idea is to increase the cost of waging
| war.
| nyadesu wrote:
| Everything has potential for military use if you try hard
| enough
| m-p-3 wrote:
| Even if they wrote down something about forbidding military
| usage, there would be no way to actually enforce that if the
| country doesn't care about license, EULA, etc.
|
| So all that does in effect is absolutely nothing other than
| political posturing.
| Datagenerator wrote:
| krageon wrote:
| Please leave this sort of pandering somewhere where it makes
| sense. Nobody comes here to read yet more state propaganda.
| actionfromafar wrote:
| _" Critical thinking is good; shallow cynicism, on the other
| hand, adds nothing of value to the community. It is
| unpleasant to read and detracts from actual work. If you have
| something important but negative to say, that's fine, but say
| it in a respectful way."_
| janjongboom wrote:
| Hey I wrote this :-) But back in 2016 or 2017, so some of the
| practical stuff might be out of date.
| dmix wrote:
| How has LoRa adoption been since then? Any interesting
| applications?
|
| Edit: it seems DASH7 is more widely deployed and apparently
| LTE-M is being pushed by telecom for IoT using existing 4G
| towers
|
| https://en.wikipedia.org/wiki/LTE-M
| wienke wrote:
| We gave an update on the state of LoRaWAN solutions and
| applications here:
| https://www.youtube.com/watch?v=vrHwgRnx6KQ&t=96s
|
| EDIT: This gives a great overview of all the available
| LoRaWAN devices out there:
| https://www.thethingsnetwork.org/device-repository/
| jimmySixDOF wrote:
| CBRS LTE is also a thing if you have 3550-3700MHz
| dang wrote:
| Year added above. Thanks!
| curiousfab wrote:
| FWIW, for building your own _private_ network, there is no need
| to rely on something like TTN (hosted by someone else - isn 't
| that a contradiction in itself?). ChirpStack
| (https://www.chirpstack.io/) is a very mature and easy to deploy
| LoRaWAN suite that's worth looking at!
| furtiman wrote:
| Fair point. The Things Stack - the server that is hosted by TTN
| - can also be installed and run locally for free, with the same
| feature set as the TTN hosted community network.
|
| https://www.thethingsindustries.com/docs/getting-started/ins...
|
| https://github.com/TheThingsNetwork/lorawan-stack
| FL410 wrote:
| Whether you believe in the crypto aspect of it or not, the Helium
| network provides really good public LoRaWAN connectivity in a lot
| of places. Much easier than building out the whole network,
| including gateways and the backend. The cool part is that the
| LoRaWAN protocol allows you to keep your data totally encrypted
| to your app, and still use public networks.
| eikaramba wrote:
| i actually build a device which is using both TTN and Helium
| exactly for that reason. https://notific.at/en
| AlexandrB wrote:
| Unfortunately, I would not build a business that relied on the
| Helium network because there's no way to tell if they're going
| to be around in a year or two. The main alternative - The
| Things Network - is quite popular in Europe but has less
| penetration in North America, unfortunately.
| asmithmd1 wrote:
| Do you know of a tutorial for getting a small LoRa device up on
| the Helium network?
| delabay wrote:
| You can start with the basic console documentation:
| https://docs.helium.com/use-the-network/console
|
| Helium is interesting because its literally everywhere in the
| US and western europe, everywhere people exist that is (not
| super remote mountainous regions).
|
| I'd bet 99% of people reading this comment section have great
| coverage.
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