Towards the modelling of complex communication networks in AutomationML

For several decades production systems were considered as closed and decoupled units, where information and network security has not been an issue. This is changing rapidly, since in the age of smart factories, production systems and office IT are growing together so as to transform entire value chains into interconnected distributed systems. By this means, production systems inherit the security challenges of office IT networks connected over the Internet. Therefore and as they tend to be operated for a much longer period of time, a prospective design of security mechanisms is mandatory. For some time, the design process of production systems gets modernised by the Automation Markup Language (AutomationML, IEC 62714). AutomationML incorporates formats of all engineering phases of production systems, thus allowing engineers to model production systems on various levels of abstraction. The language also provides building blocks for modelling the network infrastructure, which are presented in the AutomationML Communication whitepaper. However, the level of detail that can be captured is currently not sufficient for modelling most network protocols and therefore any network security concept. Therefore, we propose an extension to the AutomationML Communication whitepaper and its best practice recommendations, which allows us to model networks according to the established ISO/OSI model. Using this extension we show that concepts like network separation can be modelled and validated.