This book constitutes the joint refereed proceedings of the 21st International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networks and Systems, NEW2AN 2021, and the 14th Conference on Internet of Things and Smart Spaces, ruSMART 2021. The conference was held virtually due to the COVID-19 pandemic. The 41 revised full papers presented were carefully reviewed and selected from 118 submissions.
