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Comment by gxt | Hacker News Reader

Are there legal and plug and play LoRaWAN devices to setup a shell connection? I'm looking for simple alternatives to internet as a last resort server remote access within 10km urban area, eg between offices, to avoid physically moving to an appliance in case something breaks internet connectivity.

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I've run a shell over Meshtastic between Lilygo t-beam devices using Semtech SX1262 chips. It kinda works but is sloooooooooooow in proportion to your spreading factor and error correction choices. Internet alternative is overselling it; telemetry and short text messages are ideal, with things like shell access or low-resolution images pushing the boundaries of what is practically doable.

e: rereading I see you're specifying LoRaWAN: that's a protocol on top of the LoRa phy layer stuff, analogous to Meshtastic or Helium, not what's being implemented in this github repo

I have a T-Beam too and it is a fascinating toy, but I'm still searching a good use for it. Currently I employ it as fancy temperature sensor, but it is way overqualified for that job. I'm just curious, apart from disaster and emergency situations, what use cases do you see for a device like the T-Beam?

I use a similar device with Meshtastic for hiking. It's nice to be able to track people and communicate if you're meeting up on the trail and I've found range to be good enough to be useful on a lot of trails even if it's mostly LOS. You can also look at stuff like the Meshtastic ATAK plugin to really get into the deep end of what's possible, too.

I want to experiment with linking back to my car and maybe having kind of cellular back haul to pull in weather and stuff. Cellular is practically nonexistent even at the trailheads most places I hike so the practicality probably is limited but it's fun to tinker with. You can of course buy Garmin satphones that do something similar but with Iridium (i.e., better), but that's way less fun.

Backpacking in groups, like the sibling comment said - probably pretty pointless for a quick day hike, but quite nice if you're on a weeklong expedition where folks want to make little side jaunts without dragging the whole group along. I think one thing people don't appreciate is the realtime nature of radios - if someone in my group is off doing stuff, I need to actually pay attention to my radio to make sure I don't miss them trying to reach me. With Meshtastic, I just need to check my phone once in a while - the message will be there.

Similar usecase for overlanding: we also use several different types of voice radio, but an arrow on a map is significantly nicer than "*psssh* crackle we're somewhe...? past the 29?4 crackle turnoff fades out". Being able to mount a fuckoffhuge omni on a vehicle also helps with functional range.

I've also done the backhaul to cellular connectivity thing. Definitely fun but replicable with an inReach.

Within a few km, you're probably better off with Wifi and outdoor, directional antennas. Not sure about regulations, though.

Or, a cellular modem, which would save the installation of outdoor antennas and data-only plans are cheap.

You're allowed only very fractional duty cycle access. So depends on what you mean by "alternative to internet", but generally no.

While this is true in many cases, it's worth mentioning that many LoRA use cases can get away with high duty cyles no problem.

At the end of the day, the client devices don't have that much broadcast power - so if you run your own LoRA gateway and are not in a densely populated area, nobody cares if you use a lot of bandwidth.

Just don't use all of the bandwidth and keep monitoring the band. You can always throttle down your clients if someone else shows up.

That's a regulatory thing and depends on your location though, no?

RNode example here, but it's pretty abysmally slow due to duty cycle limitations https://unsigned.io/15-kilometre-ssh-link-with-rnode/

Seeed and RAK make modules that are ~$20 and work over AT commands, however you still need to abide by ISM bands(or relevant band plan for the country you are in) which can limit your duty cycles.

LoRa[WAN] is too limited for this use case. MTUs range from 51 to 242 bytes, and packet loss increases with packet sizes and distance. In addition, it lacks a built-in mechanism for reliability (e.g. ACKs). In other words, lots of headaches, unless your use case is sending non-critical telemetry data up to a few hundreds times per day.

For more information I recommend this paper [1] (unfortunately behind a paywall).

[1] https://ieeexplore.ieee.org/document/8030482

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