This document provides a standardized IoT Reference Architecture using a common vocabulary, reusable designs and industry best practices. It uses a top down approach, beginning with collecting the most important characteristics of IoT, abstracting those into a foundational view, then providing five more views including a construction view with a set of architecture and design patterns for building IoT systems. This second edition cancels and replaces the first edition published in 2018. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:

<UL><li>1. conformance with ISO/IEC/IEEE 42010:2022;

<li>2. improved usability;

<li>3. implementation pattern support.</UL>