B.A.T.M.A.N. Mesh Networking on ESP32’s 802.11

Mesh routing protocols are widely used in IoT and sensor networks. In recent years, the ESP32 Wi-Fi/BLE SoC became popular for prototyping IoT applications. However, the existing mesh networks for this platform lack efficient node to node communication, fast route discovery and repair, and energy efficiency. This paper addresses the formation of IEEE 802.11 based ad-hoc mesh networks without the delays inflicted by the Station to Access Point association protocol. We implemented the B.A.T.M.A.N. protocol on top of the ESP32 Wi-Fi MAC interface and integrated it into the LwIP network stack. The performance evaluation with respect to UDP/IP and TCP/IP end-to-end throughput shows the general usefulness but also identifies bottlenecks caused by limitations of the existing MAC interface. Overall, this opens an interesting opportunity for research on mesh protocols by providing a simpler platform than full featured Wi-Fi routers; and for wireless IoT applications by providing higher throughput than subGHz and BLE technologies.