ITEmIS addresses the integration of the IT and embedded domains at the level of business workflows. More specifically, ITEmIS systems are realized as workflows composing services from the two domains. This task aims at the concrete design and development of ITEmIS services & workflows both from:
- The design-, development-, and deployment-time viewpoint (see Subtasks 3.1 & 3.2), as part of the ITEmIS meta-models & tools, and
- The runtime viewpoint (see Subtask 3.3), as part of the ITEmIS service-oriented middleware.
Task 3 is decomposed into the following subtasks:
This subtask will elaborate on the workflow modelling, which will be applied to both the workflow design-time (workflow tooling) and the workflow runtime (workflow engine).
- At the highest abstraction level, a conceptual model is required for defining ITEmIS workflows, which semantically abstracts the required features of workflows and the provided features of the underlying IT/embedded systems. Capturing semantics of ITEmIS systems and their constituent IT/embedded systems at a conceptual modelling level and rigorously reasoning thereupon enable their integration at the technology-specific level.
- A first consideration concerning the workflow modelling deals with the extreme heterogeneity and special requirements found across the IT and embedded domains. ITEmIS workflows should support and integrate various interaction and coordination schemes applying to the two domains. IT services are commonly designed based on message-oriented or data-oriented interaction schemes, while embedded services employ event-oriented or data-oriented schemes, where the latter may differ considerably in terms of complexity and quantity levels from the respective IT ones. With regard to coordination schemes, both orchestration of a set of services by a central coordinator, and choreography among peer services may be envisaged. Orchestration seems to be the more investigated and easier to realize, however, choreography may be the choice for certain systems. Furthermore, the QoS features of services and the QoS required by ITEmIS workflows need to be taken into account in workflow modelling, as well as the impact of workflow interaction and coordination schemes on QoS. Based on the conceptual model for ITEmIS workflows, this subtask will further introduce an ITEmIS workflow specification language that deals with the above concerns.
- Another consideration concerns the meta-models required for the development and deployment of IT/embedded services and ITEmIS workflows. These meta models will be designed to back the following task up from the results of the preceding consideration.
This subtask will elaborate on a set of tools for the design, development and deployment of IT/embedded services and ITEmIS workflows, based on the workflow modelling provided by the previous subtask. These tools aim to enable agility by supporting the QoS-aware configuration and reconfiguration of workflows for their deployment in an ever-changing heterogeneous networking environment. ITEmIS workflows should be rapidly created, developed, deployed, reconfigured and redeployed.
This subtask will elaborate an advanced workflow engine providing the execution substrate for ITEmIS workflows. ITEmIS workflows to be executed on the engine will be expressed in the ITEmIS workflow specification language provided by Subtask 3.1. The workflow engine will allow run-time integration of the heterogeneous IT/embedded services into ITEmIS workflows, enabling the multi-faceted interoperability and scalability required for ITEmIS systems. Furthermore, the workflow engine will ensure meeting the QoS requirements of workflows by aggregating the QoS provided by the constituent IT/embedded services.