The benefits and practicalities of using Extensible Markup Language (XML) for the interfacing and control of object-oriented simulations

Traditionally simulation software has been custom built for its particular purpose with input and output file formats as well as control interfaces being unique to the simulation. This leads to considerable difficulties in preparing simulation data, utilising output data in other applications and using the simulation as a component of larger simulations. This paper presents an alternative method for the interfacing and control of simulations. This method uses an industry standard language for the implementation of interfaces and the representation of data and metadata. The use of this technique facilitates the interoperability of simulation components and provides flexibility for the development of user interfaces. It also greatly simplifies connection to external data sources such as database applications and GIS systems. This paper illustrates the benefits of using XML and XSDL using the example of the FarmSim application produced as part of the Integrated Research for Aquifer Protection (IRAP) programme. This has provided great flexibility in handling the large quantities of data associated with the simulation. The implementation of this technology has enabled an external company to develop a user interface for the paddock-level component that specifically addresses their operational requirements without any knowledge of the internal operation of simulation component. Should the user simulation component change, the user interface automatically incorporates the changes by utilising the data in the XML and XSDL structures