Meshtastic comes to Musick Point! The image shows a standalone, solar powered node mounted at the top of the building. The node is totally self contained and is maintained locally by a bluetooth connection. It’s purpose is to expand / strengthen the network by repeating data packets.
Meshtastic is a mesh network utilising low power devices operating in the “licence free” 900 MHz ISM band. It is based on the “LORA” ( Long Range) communication protocol and economic LORA hardware with the open source Meshtastic firmware providing the mesh capability.
Communication is low bandwidth, which effectively limits data to short messages ( 200 characters ). The upside of the low bandwidth is high sensitivity and the nodes can work across 10’s of km, if located in high open places. – not bad for extreme QRP!
Nodes can be configured in a number of roles including client, repeater and router. The names are not quite definitive as clients can repeat packets and routers don’t strictly route packets. The mesh software essentially works simply by nodes rebroadcasting received packets ( once per node for any packet and for a maximum pre-determined number of hops ). The software doesn’t establish routing tables. As message forwarding is essentially by broadcasting and repeating; the number of hops that a message can make needs to be limited to avoid severe flooding of a network. The hop limitation therefore limits the effective range a message might be able to be forwarded across, so the hop count is a trade off of network performance vs distance. (The hop count for a message is decremented each time the message is forwarded and the forwarding ceases when the hop count reaches zero).
So what makes it different and what is it good for? Well the fact it is relatively economic to put up a solar powered node, makes the possibility of a comprehensive network that is resilient against infrastructure failures ( mains power, internet etc ) being contributed to by anyone interested. As a mesh network, it improves in capability as more nodes are added. Additionally, as a flat mesh architecture , it is not dependant on specific servers, thereby adding another degree of resilience.
The relatively low data rate limits its applicability for for general day to day use – it is realistically limited to short text messages. However, as a backup communication mechanism when mainstream systems fail, it would be highly welcomed. Civil Defence in Hastings have installed Meshtastic nodes following communication failures after cyclone Gabriel; when some people in isolated areas were not contactable for two weeks. An array of Meshtastic nodes in high places now provides some coverage for isolated areas, and given the relatively low cost of a nodes, there is a good chance the network will strengthen as individuals add to it.