  High-performance wireless communication is crucial in digital transformation
of industrial systems which is driven by Industry 4.0 and the Industrial
Internet initiatives. Among the candidate industrial wireless technologies, 5G
(cellular/mobile) holds significant potential. Operation of private
(non-public) 5G networks in industrial environments is promising to fully
unleash this potential. This article provides a technical overview of private
5G networks. It introduces the concept and functional architecture of private
5G while highlighting the key benefits and industrial use-cases. It explores
spectrum opportunities for private 5G networks. It also discusses design
aspects of private 5G along with the key challenges. Finally, it explores the
emerging standardization and open innovation ecosystem for private 5G.
