Frequently Asked Questions about Meshtastic

What is a Mesh Network?

Unlike the Internet or mobile communications, mesh networks are special networks prioritising resilience, agility and flexibility above all else. To do this, they allow for every node or member of the network to have the ability to receive and pass-on messages destined for others, while at the same time sending and receiving messages like any other.

In this way, every member of the network can function as messaging infrastructure, message sender and message recipient at the same time. This is quite unlike our experience as members of the network of networks called the Internet, where a laptop or phone only really sends and receives information - they don't fulfill a role in the network's carrying capacity or health.

It is for these reasons that mesh networks are used in highly changeable environments, especially where nodes are mobile or in unstable operating situations (like disasters). If there is a change in the network structure - for instance, some nodes stop functioning or have to change location - messages can still be delivered via other routes (paths) through other nodes. In this sense, some describe mesh networks as having the unique ability to 'self-heal' - a very desireable feature when things don't quite go to plan.

What about Meshastic?

Meshtastic is a special mesh networking implementation built atop the low-power and long-range radio standard LoRa (for Long range Radio), and goes a step further. It allows for a mix of both stationary nodes more akin to traditional networking (fulfilling roles like cell towers or routers), with mobile nodes (for instance in people's bags or vehicles) alongside. This hybridity makes it especially interesting as a fallback network in disaster scenarios, and can cover large geographical regions.

How do Meshtastic nodes communicate?

Like all wireless communication implementations (WiFi, 4g and 5g), Meshtastic is at root a radio platform. But unlike the analog radios most will think of when citing the word 'radio', Meshtastic encodes its information digitally with the LoRa (Long range Radio) signal technology underneath. Simply put, you can think of LoRa as the actual radio part responsible for the links between antennae, with Meshtastic as the communication protocol and messaging solution atop.

Radio communication works best 'line of sight' (LoS), and in the case of LoRa and Meshtastic, that's just as true. A slightly misleading term, LoS does not mean that the other node has to be visible to the eye, rather that a line can be drawn between two communicating nodes without any obstruction (occlusion) in the way. Further, while some messages may pass through a wooden home, they may not a building made of metal and concrete - lest of all a hill - and so for this reason it's a always a good idea to work with the environment when building up a mesh. Thankfully, as Meshtastic nodes can have certain 'roles', a node up on a hill with line-of-sight to nodes either side of it can be set up as a special 'repeater' role, effectively conjoining whole geographical areas. Such nodes act as bridges and are a big part of what makes the Wellington region mesh work so well.

What data can I send with Meshtastic?

Meshtastic is solely for text messaging, for messages a couple of hundred characters long. While you can use your favourite emojis, there is no possibility of voice messages nor attaching files.

Sending and Receiving Messages with Meshtastic

With the exception of a couple of nodes that come with their own keyboards, an important thing to understand with Meshtastic is that a smartphone is required to use them. The smartphone is connected to the node via Bluetooth, and a special Meshtastic app is installed on that phone and used to browse the mesh network map, send direct messages or even messages to group chats.

However, just like the old school radios - where if you aren't near a radio when the broadcast happens you'll miss it - a Meshtastic node must be on the mesh to receive messages destined to it. This is different from, say, WhatsApp or Signal, whereby if your phone is off when the message is sent, that message can be retrieved automatically from the server later when the phone is on again. Understanding this important difference will help you get the most from your mesh networking experience.

Further, if your phone is not connected to a node that is on the mesh at the point of delivery, and connects (via Bluetooth) to the node later, only the most recent messages will be visible.

For this reason it can be a good idea to have a node in your home with a device (like a cheap Android tablet) always powered and connected to it, such that you never miss a beat.

What if I want to create a separate network?

Those ambitious and with more technical expertise may want to create a separate Meshtastic network, running in parallel with that of the existing Wellington SHORT_FAST mesh.

While great, a few basics need to be outlined in advance:

Avoid placing fixed nodes next to existing Wellington Meshtastic nodes, as they may impact signal quality for nodes of both networks.
Check that the Frequency Override value for your new mesh does not overlap with any existing. For instance, the value for the Wellington mesh is 918.875MHz.
Think topologically and work with the terrain when deploying. Choose fewer high altitude vantage points with broad viewsheds over many nodes with less visibility.
Use the Meshtastic roles strategically, thinking clearly about traffic flow. For instance, fixed nodes on high vantage points should be either ROUTER or REPEATER roles, particularly the latter if it does not need to send any telemetry. Note that when choosing these roles you are telling nodes around to select these nodes over all others for their route, so be sure to design for that to give the best outcome. Encourage your mesh's membership to do the same, with CLIENT_BASE for their own stationary nodes at home or work, and CLIENT_MUTE for their daily driver mobile nodes. This can significantly reduce needless network congestion. If you are building out to geography with no other route to your mesh, such that all future nodes will use your new fixed node, consider ROUTER_LATE for that role.
Be sure to create a 'backchannel' for your mesh. A place to discuss the mesh off-mesh. This could be a Discourse forum, or a Signal group. Such a space can act as a landing point for onboarding, but also support, ideas, notices and mesh related activities.