Meshtastic began with a straightforward goal: to keep hiking buddies connected in the outdoors when cell service was unavailable. What started as a simple project has grown, thanks to a passionate community pushing the boundaries of what's possible. Today, Meshtastic is used in Search and Rescue operations, off-grid communication, disaster recovery, and even grid-down scenarios. Whether it's preparing for the next flood or tornado, extending communication over the Internet with MQTT, or simply enjoying an off-grid adventure, Meshtastic has become an essential tool for many.

The Meshtastic project-hosted MQTT server, which allows sharing mesh traffic over the Internet, has recently made an important change that impacts the way information is shared via MQTT: the ability to subscribe to all topics has been removed. However, users can still subscribe to regional topics, such as msh/US/#, to view nodes in their specific area. The MQTT functionality remains intact, public maps are still accessible, and users can continue to see nodes within their specified regions with some new changes.

Designing a low-bandwidth wireless mesh network to run on low-power microprocessors with limited memory is challenging. Arguably the simplest mesh routing protocol is Flood Routing: each radio receiving a packet will rebroadcast this again, up to a defined hop limit. Although Meshtastic is based on this strategy, there are a few subtle, but significant enhancements. Most importantly, before a node rebroadcasts, it waits a short while and listens if anyone else is already rebroadcasting. If so, it will not rebroadcast again. Therefore, “Managed Flood Routing” would be a better name. For more details on the enhancements, please review our documentation.

The Federal Communications Commission (FCC) is currently considering a proposal from NextNav that could drastically reshape the 900 MHz band. While this proposal may seem like just another routine reconfiguration, it has significant implications for a broad range of users, particularly those who rely on unlicensed spectrum for innovative, community-driven projects. At the heart of the debate lies the potential impact on open-source initiatives like Meshtastic, an open-source, decentralized communication platform that operates in the 900 MHz ISM band.