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Extensible Open Distributed Simulation Platform
The Context
The EODiSP is a generic platform to support the development and operation of distributed simulators. The EODiSP is targeted at complex end-to-end simulations, consisting of several specialist simulation packages. A simulation package encapsulates one or more simulation models. An EODiSP simulation is built by integrating a set of these simulation packages with the EODiSP infrastructure.

Simulation packages can take a variety of forms: source code in a high-level language, binary level executable, macros in an excel spreadsheet, etc. With the EODiSP approach, simulation engineers can encapsulate existing simulation packages and models required for an overall simulation, and subsequently integrate them to interact together over a possibly distributed network.

The EODiSP is specifically intended to allow the integration of heterogeneous and distributed simulation packages. In particular, the EODiSP allows the seamless integration of simulation packages that differ with respect to their implementation technology and to their target operating system. Integration of packages available both as source code and as binary executables is possible. The strength of the EODiSP environment is its capability to integrate these packages without any changes to the existing implementation of the simulation packages.  
The Architecture
The EODiSP is built as a partial implementation of the High-Level Architecture or HLA. The HLA is the most widely used distributed simulation architecture. It is defined as an IEEE standard. Adherence to the standard allows interoperability and reusability of simulation packages. The HLA is defined as a set of services that support various aspects of a simulation. In general, a particular simulator will only need a subset of all the services defined by the HLA. At present, the EODiSP only implements the subset of HLA services selected to support data-driven simulations. The architecture allows implementing additional HLA services in the future.

The EODiSP provides an infrastructure to allow the integration of heterogeneous simulation packages. The HLA defines the interface between the entities participating in a simulation and the simulation infrastructure. Hence, in order to be integrated with the EODiSP infrastructure, simulation packages must comply with this HLA interface. Since the EODiSP approach is based on the integration of existing simulation packages which are not a priori HLA compliant, the platform supports the concept of wrapper. A wrapper is a piece of code that adapts the external interface of a simulation package to make it comply with the HLA requirements. The EODiSP predefines wrappers for commonly used simulation packages (Matlab-based packages; excel-based packages; packages implemented as Java or C/C++ source code; packages implemented as Windows, Linux, or Unix executables; etc).

The EODiSP defines two GUI-based applications that can be used to manage existing simulation packages in a centralized repository, to configure them to build a simulation, and to control the execution of the simulation.
Free software
The EODiSP will be provided as free and open software under a General Public Licence (TBC) and can be downloaded from its project web site. The EODiSP was developed under ESA contract 1 8833/05/NL/AR. Its development followed a formal development process based on the ECSS-E40. The environment will be provided together with a complete verification data package including in particular both unit and system level tests and a full instantiation of a representative demonstrator simulation.
Last update: 21 July 2006


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