OpenThread is a portable and flexible open-source implementation of the Thread networking protocol. It has been created by Google in active collaboration with Nordic Semiconductor, to accelerate the development of products for the connected home.
The Thread implementation in the nRF Connect SDK is based on the OpenThread stack, which is integrated into Zephyr.
You can find the OpenThread stack in
Among others, OpenThread has the following main advantages:
A narrow platform abstraction layer that makes the OpenThread platform-agnostic
Small memory footprint
Support for system-on-chip (SoC) as well as network co-processor (NCP) and radio co-processor (RCP) designs
Official Thread certification
You can find more information about OpenThread at OpenThread.io.