Assessment of IEC-61499 and CDL for Function Block composition in factory-wide system integration

Factory Information Systems (FIS) are clustered with a variety of heterogeneous systems using different protocols making integration tasks complex and time consuming. A common practice for integration of large applications is modularity and servitization as seen in the Service Oriented Computing (SOC) paradigms. Services can be encapsulated as a Function Block (FB) according to IEC-61499 standard bridging the gap between shop-floors and Information Technology (IT) distributed systems. This approach eases the task to describe the overall system in a single descriptive language. However, along with all these concepts comes the critical task of ensuring trustful communication between distributed modular functions to transform the atomic functionality into processes. One of the main challenges for function composition is the need to establish the interactions between the compatible modules to compose a process. This encourages the use of a rich descriptive language as a control strategy to manage the exchange of messages and to define the connections among the services. Primarily, this paper provides a contrast for Function Block composition using IEC-61499 and Choreography Description Languages (CDL) for Function Block based integration. The results are later evaluated within the PLANTCockpit´s Function Block Engine reference architecture for deployment of Function Block Networks (FBNs).