  The digitalization of manufacturing processes is expected to lead to a
growing interconnection of production sites, as well as machines, tools and
work pieces. In the course of this development, new use-cases arise which have
challenging requirements from a communication technology point of view. In this
paper we propose a communication network architecture for Industry 4.0
applications, which combines new 5G and non-cellular wireless network
technologies with existing (wired) fieldbus technologies on the shop floor.
This architecture includes the possibility to use private and public mobile
networks together with local networking technologies to achieve a flexible
setup that addresses many different industrial use cases. It is embedded into
the Industrial Internet Reference Architecture and the RAMI4.0 reference
architecture. The paper shows how the advancements introduced around the new 5G
mobile technology can fulfill a wide range of industry requirements and thus
enable new Industry 4.0 applications. Since 5G standardization is still
ongoing, the proposed architecture is in a first step mainly focusing on new
advanced features in the core network, but will be developed further later.
