Cyber-physical systems (CPS) have shaped the discussion about Industrie 4.0 for some time. For ensuring the competitiveness of producing enterprises the vision for the future figures out cyber-physical production systems (CPPS) as a core component of a modern factory. Adaptability and coping with complexity are (among others) potentials of this new generation of production management. The succesful transformation of this theoretical construct into the practical implementation can only take place with regard to the conditions characterizing the context of a factory. The subject of this contribution is a concept that takes up the brown field character and describes a solution for CPS-extension of existing (legacy) systems.