XML technologies to design didactical distributed measurement laboratories

Laboratory activity is an open challenge for on-line teaching applied to scientific domains. The remote control of instrumentation and the execution of real experiments via Internet are topics of interest for many researchers. This paper introduces the model of a virtual laboratory that allows practicing via Internet in real laboratories spread on a wide area network. It is based on a main virtual laboratory server (VLS), one or more real laboratory servers (RLS) and client stations. Real laboratory servers control instrumentation and drive experiments. The network links all the distributed software components of the environment. The paper focuses on the use of XML (Extensible Markup Language) and its related technologies to support the development of such environment. XML plays a central role in the definition of the environment (instruments, experiments and users activities) and in the maintenance process. These technologies are very promising to address scalability and interoperability among distributed software applications and to facilitate information reuse ensuring data coherency, completeness and reliability. The proposed data organization results effective to develop, maintain and scale up the environment and facilitates the cooperation and the contribution of many partners to the virtual laboratory project.