Leah L | LoRa: Decentralized Messaging & How it Works | Common S3nse - 2026

[music] Who here knows about mesh messaging? Okay. Who thinks that this is the future of how we will have to self-organize and communicate with each other? Huh. Interesting.

I got two and I got a feel like are we all Are we Is it game?

We're game. Let's go. Take the stage. Round of applause for Leah. [applause and cheering]

Hello. Thank you for coming and listening to me y about messaging people. Um, so I'm going to be talking about something pretty cool. It's a technology that you might be familiar with if you've used something called Bit Chat. Has anyone here used Bit Chat?

It's like Bit Chat but different and it's better. Um, so Laura is it allows you to do decentralized messaging. And so I'm going to talk about how it works. So decentralized, it's peer-to-peer and it's over a mesh network and it uses something called Laura, which is long range radio. And that's the physical layer that makes all of this possible.

So what the heck are you looking at right here? Confusion. I'm going to explain. Um, so Laura uses a new radio frequency modulation method. Um, it's called, uh, And basically what it does it it allows you to communicate long range with low power consumption using chirp modulation.

Um and so we can see here here's an example of what a chirp looks like. And so something like meshtastic will use this or mesh core uh to send packets over the air. So we have three protocols that all use Laura long range radio. And the first one is Meshtastic. It's the most common.

It's very popular. It's very easy to use. Um it's a messaging firmware and it's also an app. Then we've got Meshcore which is another alternative to Meshtastic. It's a bit newer and it's also messaging and an app.

Then we've got um a networking stack called Reticulum which also uses Laura and it's basically like a full TCP IP um recreation using long range radio as a mechanism of transmission. So I'm going to start talking off um talking about meshtastic. So it's pretty popular um and it's very very easy to use. allows you to have off-grid communication with everyone. Meaning, you don't need internet, you don't need Bluetooth, you don't need uh Ethernet, Wi-Fi, anything.

You can just use your radio like this guy. This one here is running Meshtastic. You can put it on your phone and it works very easy over the app. So, Meshic, it's long range. Uh maximum of 331 kilometers have been recorded.

Uh you don't need a phone, but you can like pair it really easily with something like this um uh to use the phone app as well. So you can flash pair your phone a message in 10 minutes, but you can also get standalone versions of these which you don't require a phone at all. Um so it's completely decentralized. It's peer-to-peer. There's no router involved at all and you can send and receive messages as well as have optional GPS location features.

So, how it works is that when you're sending a message on meshtestic um it's relayed using the Laura radio using Bluetooth or Wi-Fi or Ethernet or serial con connection. Then the message is broadcast by the radio. And if it hasn't received confirmation from any other device after a certain time, the radio will retransmit that message up to three times. And to receive a message, it works by uh capturing the packet. It checks to see if it's heard the message before and if the radio has, it ignores the message.

If it hasn't, it will then rebroadcast it to other nodes on the network. And for rebroadcasting, for each message a radio rebroadcast, um it marks the hop limit down by one. And so when a radio receives a packet with a hop limit of zero, it will not rebroadcast a message anymore. Um meshtastic also allows the radio to store packets. So the radio stores a small amount of packets around 30 in memory um when it's not colle connected to a client app and if the storage is full uh it replaces the packets um with newly incoming messages so you get updated um and mesh also uses encryption.

So all chat channels use AES 256CTR encryption and DMs have recently been updated to use public key cryptography as well as AESCM uh encryption as of version 2.5. So I'm going to talk a bit more about technical stuff. So this is some examples of some hardware that you can use to run Meshastic on. As you can see I've got the Heltech Mesh Pocket up here.

It's got an E in screen. uh it's lasts forever on a charge and you can also use it as a battery bank as well. Um so talking about the technicalities again so all channels are encrypted uh public cryptography for DM since 2.5 and um every node on the network relays by default um and the routing that is used by meshtastic is something called manage flooding for broadcast. Bit about how this works.

So a node receiving a broadcast will uh schedule a re rebroadcast after a delay and this delay is awaited by a received signal to noise ratio and a not a node that hears a message weekly is then assumed to be far away. So it gets a shorter delay and uh rebroadcast first and so distance is inferred in this the system by um signal quality itself not from GPS or topology knowledge. So if a node hears the same packet rebroadcast by someone else before the timer fires it will cancel. So the mesh network using in meshtastic preferentially relays um by the most distant node that heard it and it will suppress any redundant copies. Um it also uses congestion control mechanisms like managed flood suppression um duplicate ID packet tracking and regulatory cycle duty limits as well as um uh telemetry uh since version 2.

4 where node info autotunes the cadence based on the network size. Um so and as well in version 2.6 they introduced next hop routing as a mechanism. So uh for DM specifically so the network to learn which neighbor has relayed successfully, then send the specific next hop. Send send it via that specific next hop rather than reflooding the entire network.

And this drops the DM cost to about like one transmission per hop after the initial discovery flood, which is pretty good. Yeah. Um so yeah, it like the maximum hop limit on this network is seven. Um and the high it does have high network traffic in comparison to mesh mesh call which is another alternative protocol um because of the flooding mechanism. So I'll go to the next slide.

So going to explain a bit about how the nodes in meshtastic work. So a radio like this guy um it has four core components. It's got a Laura radio chip for radio frequency transmission. common one is SX1262 and it's also got a microcontroller for firmware as well as um so like that would be the ESB32 for Bluetooth and Wi-Fi as well as an antenna and a power source to keep it alive. Um and so within the mesh testic network nodes have various roles.

So a client node is the default role for most people that want to join and configure and send messages. um because it sends and receives messages. It will forward packets. Um it hears only if no better position node can pick it up. Um and it will listen before rebroadcasting to keep airtime usage efficient.

So, oh no, my mouse is not working. Sorry guys. No, I'm all good. Um and so then you have uh another different node roles like the client meet node. So, this is the same as a client, but it won't forward anything.

And you would have to use this on your configuration with if you've got two or more devices running on the same mesh. So, your second or third one of these should be on mute so they don't create any duplicate board broadcasts and heat up any hot budget. Um, and then there's the role of a client-based node, which is similar to client, but it prioritizes rebroadcasting uh from or to any of its favored nodes. And this role is useful when you want to ensure any nearby nodes make full use of your wellpositioned stronger base station node as well. We've got something called a router node.

And this will always rebroadcast and it will cut ahead of any nodes in the relay queue. So it's really powerful in the right spot if you're wanting to connect and create your own mesh network, but it can be harmful in the wrong one. Um, and you should only assign a router role to a node at a high elevation with a good line of sight. Then there is the router late role. So that's a mandatory rebroadcast role.

Um it always repeats packets adhes and waits to detect if another router is already handling it. And so this is good for sites that are critical for coverage but are not optimately placed. So such as a rooftop that covers a dead zone or a node filling a gap where your main router can't reach. And then we have the repeater roll. So this will relay packets like a router but it broadcasts nothing about itself.

So, it's basically a little ghost in the mesh rebroadcasting packets for everyone else. And then there's a really cool thing like a sensor. And so, this is part of the um the network that it basically just collects and retransmits environmental data. So, it can monitor temperature, humidity, air quality, and it will just go back to sleep and then wake up when um it needs to send more information. So, that's a bit about meshtastic.

It's great for messaging, but it's also really good for a whole range of things. Now, I want to talk to you about Mesh Core. It's a good alternative to Meshtastic. Um, it's another simple plugin and play flasher device. You just need a handheld radio to use it.

Um, and it's also low power, long range, and completely decentralized. Uh, Metcore has a bit more range than Metastic because it's more infrastructure based. Um, so you can go up to 5 to 65 km with just device direct links. Um and the key feature that distinguishes it from meshtastic is that it uses something called multihop packet routing. So basically what that means is the messages travel across um multiple intermediate devices until they re reach their destination.

So for example a packet would travel from phone A to companion node one and then to repeater one then to repeater two then to companion node two and then to phone B. And each node in this system helps extend the network's coverage. So it can cover even larger areas with few devices. Um and because the messages can all take multiple paths, this increases the resilience of the network if an individual node goes offline. Um as well like meshtastic mesh core is encrypted.

So group channels use um PSK to encrypt traffic via AES128 ECB. Um and there's also key exchange for DMs um via ED25519 key pairs. And some common hardware is that uh also shared with Matchtastic is that they use ESP32 microcontrollers um the chips as well as the antenna and your power supply. Um so with mesh core it has a 64 hop limit which is a bit bigger than um quite a bit bigger than meshtastics because of the routing mechanism it uses. Um and it also has optional GPS location features.

So the roles in mesh core the network is a bit different like I said because the focus of mesh core is to separate the people from the infrastructure itself. With meshtastic it's like oh you run this thing everyone does everyone's job. If you want to do this job you can get this node to do it. But mesh core is a bit more uh separated. It's got more roles.

So node roles include things like um companion node. So this will provide uh UI to the network. Um it allows you to send and receive messages and interact with the mesh communication channels. So this would be something like your smartphone, your laptop or handheld radio like this guy. Um and then uh we've got things called repeaters.

So, [clears throat] sorry. Uh, repeater nodes are typically installed in fixed locations such as rooftops, towers, hills, tall buildings. Um, and because they're stationary and strategically placed, they provide more reliable routing than with mobile parts. And I just wanted to say a quick note on the design of the separation of node roles. So unlike um infrastructure nodes, companion nodes themselves, they can't forward packets and they don't forward any packets for any users.

So this helps prevent unstable routing paths caused by mobile devices moving around like this guy if you're in your pocket and you're walking. Um so instead packet forwarding is handled dedicated infrastructure nodes like repeaters and um room servers. And coming back to that, so room servers, they provide the core feature of messaging persistence. So um unlike repeaters that forward packets, um room servers themselves store messages as well and that allows you to retrieve them later. So this allows for asynchronous communication.

So users don't need to always be connected at to the network at the same time. Um so it basically behaves like a basic bulletin board system. Um, and just to let you know, um, a room server can be set to repeat packets, but it's not recommended. It's best to use a separate device for a repeater and a room server if you're setting up a mesh core network because a room server with repeating enabled or lacks lacks the full feature set that you need for dedicated repeater. And um, here are some examples of some common companion node devices.

We've got examples of standalone nodes themselves and some a repeater node up there. Oh, I'm going too fast. We're back. Yeah. So, quick hash about the routing mechanism that Mesh Core uses.

So, it's a repeater based model. Um, it uses flood, then direct source routing with three phases. So, we've got discovery, flood, path return, c direct, and then recovery if the path goes stale. and the group and public channels will always flood. There's also rate limit limiters that exist for discovery floods and anonymous room server login.

And um this is great because um it's used for very much planned and scalable static networks via Laura and uh the mechanism itself reduces airtime congestion by separating the user devices the companions from the routing nodes through repeaters um allowing it to have 64 hops compared to mesht 6 7 um if you want to go into detail about the routing we can talk about that later but I'm going to move along for time sake. Um, but quickly I wanted to say because I've tried both Meshtastic and Meshcore, a caveat I noticed with Meshtastic is that the app has been a bit unreliable um when pulling the it pulls a location from the phone's GPS instead of the onboard GPS on this guy, but um they're both very easy to use and maybe they'll figure that out soon. Now I want to talk about Reticulum. This is a whole new imagining of the internet which is really freaking cool. It's literally a cryptography first networking stack.

It completely replaces TCP IP and you can build or use any application on top of it. Um, and so it uses Laura links. It uses Wi-Fi and Ethernet and public internet all simultaneously. So anyone can make and join almost entirely self-organizing networks. And these are all completely decentralized.

Um and it's completely um it's written in Python. Uh the reticulum is written in Python. Um and it's identity based as well. Um there's no source address involved. There is so there would be like identity based there's no IP, there's no MAC, there's no numeric ID node.

It's all just node self selfissue keys and the packets themselves carry on to the destination. Um and with forward secrecy all links use ephemeral ECDH keys as well. And routing is uh announcement based hop by hop next routing. And with reticulum you can achieve theoretically unlimited amount of hops on this network but people like to say it's a maximum of 128. Um and the benefits of reticulum compared to these other um Laura [clears throat] protocols is that um it works well it it does a lot more basically.

So um it works on reliable low bandwidth links. It has automatic control between fast and slow segments and that's something that neither meshtastic nor mesh core have. Um as well it has an entire application layer. Um and this includes Alexf which is a resilient um messaging protocol with store and forward for offline nodes. Um there's also apps like Nomad Network and um this [clears throat] allows things like uh voice calls, file transfer, remote shell access.

And the target audience for Reticulum is a bit different to that of Meshcore and Meshtastic. So it's for builders and devs who want a full toolkit um over their network, not just a messaging app. And it's also entirely encrypted. Um it's actually more anonymous than mesh core or meshtastic because intermediate nodes will forward based on a locally maintained next hop state. And um yeah, it's really cool.

Uh and and the initiator itself has no uh has a complete anom anonymity. There's no source address listed in any single packet that's trans transmitted over reticulum. So yeah, it's identity based, not address based at all. And so I'm going to show you the four layers of the reticulum network. So start is the identity layer.

Then we've got our interfaces layer, our routing layer. So and then we've got the application layer at the top. Um and so I wanted to briefly mention messaging on Reticulum. So you can use this really cool thing called LXMF. Uh it allows you to have Okay.

I I have to wrap up, but yeah, check out this thing. It's really cool. There's Nomadnet that allows you to message people and host micro websites on Reticulum. You don't need internet. You can access websites without it.

Sideband's a great messaging app. And Reticulum Mesh Chat allows you to interact with all of the above. Sideband and Nomad Net. Um yeah, and here's a quick display of some other hardware you can look at if you want to get involved in mesh. Yeah.

And finally, uh, if you want to set up a Laura mesh quickly, use mesh stick, keep it simple. If you want to use, uh, if you want privacy and encryption and like sharing files and voice messages and want to combine the internet and Laura and you're willing to run it on a computer, use Reticulum because Reticulum does need a separate computer as well as one of your nodes. Thanks, guys. So go for it.

That last slide um made me think that feels like a perfect companion to like a Hermes agent running on by, isn't it?

Um I got to say I'm not familiar with a Hermes agent, so I don't know how to answer that one. Sorry. Okay,

I think it's everyone. I Justin told me he's obsessed with Hermes as well. Every I think half of people in this room probably use Hermes. It's an AI agent uh that can Well, I personally run one of them on on Pi uh and uh

um you can set it up with uh with all kinds of

uh messaging, signal, WhatsApp, whatever.

Looking at it, it feels like yeah, I could get my Hermes or I could talk with my Hermes over reticle. Yeah, if it's low bandwidth enough, you can host it on a Micron page on Reticulum and it can be completely separate from the internet. And there's a massive community of people that are using these Micron pages to do things like that, which is really cool.

Yeah, another question.

Trying to set this up in Liberland for like last year and still doesn't work. But not I think just missing somebody. Are you able to deploy somebody to help us to cover? Yeah, I'll be your networking gal.

Amazing. Amazing. Please, please.

How are you running a reticulum or is it one of mesh mesh test?

They bought like bunch of hardware mesh testic but you know they're struggling you know always this firmware. They set up you know the shop and they upload the firmware into the boxes and it doesn't work.

Yeah,

I think we tried like three times but we need somebody that knows what he's doing. So we really appreciate

Yeah. Well, hit me up if you want to chat more about that.

Yeah. Liber.

Yeah. Liberal land for Laura. Laura for Liverland. Let's go.

Nice. Wait, I'll take I think I still had one question. No. Or did I listen? Yeah, I still had one question.

You still you're in demand.

What sort of uh use cases do you see for these kind of um networks? like uh I know like uh you know mesh meshtestic and mesh core are bit more about sort of sending short textbased messages um and um you know I'm just wondering like how do you see these things being actually really used as opposed to you know just doing stuff encrypted on the internet.

Yeah that's a great question. Um I think that there is a lot of use cases and we've seen quite a few happening already. Um in if we want to talk about a bit about like real world examples, I know that uh in places where the internet has been cut off by government censorship or you know you live out in rural Australia for example, you can still access websites and communicate with your friends and family or you know if there's an emergency as well. um disaster response teams use a lot of this stuff because it's so um it's it's so hard to take down compared to like other infrastructure. And um yeah, I I recently saw a video of uh people um in war zones uh connecting over reticulum.

So it's it's good for people in crisis and sticky situations.

Last question. No. Okay. Yeah. No.

All right. Well, round of applause for Leah. Thank you so much,

guys. Was my first talk. Hope I didn't be too rusty.

You rocked it.