Harmonized and Consistent Data Management in Distributed Automation Systems: the NOAH Approach

This paper reports some results obtained by the authors within the Work Package 4 (WP4) of the ESPRIT project 26951 - Network Oriented Application Harmonisation (NOAH). The main goal of the NOAH Project is to define concepts, models and tools as elements of an open platform for distributed automation systems as independent as possible of the today available technologies. One of the point addressed in the NOAH Project is how to provide a common view of the system in such a way that any application, independently of its features, can be described by focusing on all the system composing elements including issues related to functional and physical distribution. The Data Base Repository (DBR) specification is the solution proposed to address this issue. It defines a common and general information model which provides a unified perspective for several activities including installation, configuration, maintenance and technical management, as well as a unified approach to the problem of describing complex distributed systems. In this work we deal with the specification of basic main operations to be carried out on Database Repository. In particular, in the paper a description of data distribution in the NOAH model is given, and the Manager/Agent model, that is the basic interaction mode devised for data management, is introduced. Then data consistency issues in the NOAH DBR are outlined.