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Comment by ianpenney | Hacker News Reader

I’ve been wondering this for a while and maybe someone has a clue.

Based on the very “bursty” nature of LoRA, how much does an adversary need to spend to radiolocate it? What’s the threat model there?

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$20? These networks do not try to hide your location and triangulating known frequencies is trivial.

How trivial is it, really? These are spread spectrum devices that could have very sparse duty cycles. If you sending only millisecond bursts a couple of times an hour, for telemetry and whatnot, it would seem pretty hard to get a good fix, especially when moving. I haven't analyzed lora traffic, so just talking out of my ass.

LoRa uses chirping which are much longer than milliseconds. You can clearly see them in a spectrum display. It's a very slow protocol. Not as slow as WISPR or JT8 but still slow. The flip side is that it's robust (the chirping provides a lot of interference protection against fixed-frequency interference for example)

With a couple of GPS-synchronized receivers stationed in an area, child's play. LoRA airtime is extraordinarily long for common spreading factors.

Sdrs are super cheap these days. It wouldn't be hard.

Note: did things in .mil

You could get a rough location for free. Every time you send a message, “observer” nodes connected to the internet publish the packet, and in the packet is the repeater path taken, repeaters have known locations and the first repeater is going to be near you.

If its meshtastic, just keep sending traceroutes until you triangulate the node.

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