ESP-NOW and LoRa communication

Espressif Systems developed ESP-NOW to enable ESP8266 and ESP32 microcontrollers to communicate without requiring a Wi-Fi connection. ESP-NOW operates at 2.4 GHz, the same frequency as Wi-Fi and Bluetooth, with microcontrollers paired prior to communication. A microcontroller transmits and receives messages to and from several microcontrollers, with a network consisting of 20 microcontrollers without message encryption, but 10 microcontrollers with encryption. If power to a microcontroller is lost and then restored, the microcontroller automatically reconnects to the paired microcontroller. In practice, a transmission range of 250 m over open ground was achieved with two ESP32 microcontrollers.