On the Interoperability of DEVS components: On-Line vs. Off-Line Strategies

During the last years, the DEVS community provides many contributions towards the realization of a world-wide platform for collaborative Modeling & Simulation. The goal of such a platform would be to enable the sharing and reuse of models between scientists, as well as the seamless simulation of distributed and heterogeneous models. Therefore, one of the major research fields is the definition of architectures for integrating heterogeneous DEVS components, meaning simulators and/or models written in different frameworks and programming languages. In this work, we present three different strategies for providing such interoperability between DEVS components. The first focuses on standardizing exchanges between simulators, and has been explored in previous works. The two others strategies are more prospective; in keeping with Model-Driven Engineering, they place the model at the center of their architecture and make extensive use of model transformations. To make this possible, we defined a platform and language-independent format for describing and sharing DEVS models, called DEVS Markup Language

Interoperability between DEVS Simulators using Service Oriented Architecture and DEVS Namespace

Interoperability between heterogeneous software systems is an important issue to increase software reusability in the software industry. Many methods are proposed to implement interoperable systems using distributed computing infrastructures such as CORBA, HLA and SOA. Those infrastructures can provide communication channels between software systems with heterogeneous environments. SOA (Service Oriented Architecture) provides a more flexible approach to interoperability than do the others because it provides platform independence and employs platform-neutral message passing with Simple Object Access Protocol (SOAP) to communicate between a service and a client.The main contribution of this study is to design and implement an interoperable DEVS simulation environment using the SOA concept and a new construct called the DEVS namespace. The interoperable DEVS environment consists of a DEVS simulator service and an associated integrator. The DEVS simulator service provides both simulator level and model level interoperability. Moreover, using the DEVS namespace, DEVS simulator services can be interoperable with any services using the same message types.To demonstrate the utility of the proposed environment, we describe various applications of the interoperable DEVS simulation environment. The applications are drawn from real world development of automated testing environments for military information system interoperability. A radar track generation and display federation and a model negotiation web service illustrated the ability of the proposed middleware to work across platforms and languages. Its ability to support higher level semantic interoperability will be demonstrated in a testing service that can deploy model agents to provide coordinated observation of web requests of participants in simulated distributed scenarios

Design of a Framework to Measure the Degree of Live Virtual Constructive (LVC) Simulation Interoperability

Accomplishment of the Live, Virtual and Constructive simulation interoperability has been a major goal and a challenge in the Modeling and Simulation (M&S) community. There have been efforts to interoperate individual Live, Virtual and Constructive simulations within a common synthetic environment through suitable technologies such as interface specifications, protocols, and standard middleware architectures. However, achieving interoperability of LVC simulation is a technologically complex since it is affected by multiple factors, and the characteristics are not yet satisfactorily defined and studied. A proper method is absent to measure the potential interoperability degree of LVC simulation. Therefore, there should be an appropriate systematic approach to measure the potential LVC simulation interoperability which includes technical, conceptual and organizational domains. This research aims to design a preliminary systematic approach to measure the potential interoperability degree of an individual Live, Virtual and Constructive simulation and a relevant organization which plans to use the simulation system for simulation interoperability. Specifically, a framework that contains components such as a) LVC simulation interoperability domains, b) interoperability domain factors, c) interoperability maturity levels, d) interoperability determination method is proposed. To accomplish the goal, a set of factors that determine the interoperability degree in LVC simulation environment are identified, and the factors are used to build the key elements of the framework. The proposed methodology for the framework design is based on systematic literature reviews and a survey involving a number of relevant domain experts. A case study is demonstrated to prove the validity and effectiveness of the developed framework. The case study illustrates how the interoperability levels of a simulation system and a relevant organization are effectively measured. This research potentially contributes by providing an understanding of the factors that determine the interoperability degree of LVC simulation, improvement of the LVC simulation interoperability measurement process, and consequently, accomplishment of more effective LVC simulation interoperability