Open Source Summit Europe 2022

When designing battery-powered devices, wireless connectivity is a sore point for the power budget. Wi-Fi is easily available, but drains batteries fast. Bluetooth LE on the other hand helps to conserve power, but suffers from higher latency and limited use compared to a full mesh network with IP connectivity. Thread offers a sweetspot in-between by using low-power transceivers, mesh capabilities and IPv6. In this talk Stefan looks at the technical aspects of integrating and using OpenThread for your project or product. With the goal to operate on a coin-cell battery for months, or even years, while still maintaining connectivity to the local mesh network in your home and, if wanted, to the cloud. Stefan starts with discussing operations on bare-metal, RTOS and Linux. Followed by a deep dive into the technologies OpenThread uses and explanations on how they work: 6lowpan to adapt IPv6 to the limitations of the 802.15.4 physical and mac layers. IPv6 to allow for for link-local, mesh and global addresses and routing. Recent additions to mDNS to allow for a discovery proxy (rfc8766) in combination with the newly developed Service Registration Protocol (draft-ietf-dnssd-srp). The later combination allows to avoid flooding mDNS messages on the low-power network to save power.