QoS-Based Middleware Architecture for Distributed Control Systems

This paper presents an implementation of a middleware architecture to control distributed systems. The main objective is providing a QoS level between the communications layer and the control layer. This architecture is based on the use of a hierarchical communications structure called “logical namespace tree” and a structured set of control processes interconnected, called “logical sensors graph”. This architecture is named Frame Sensor Adapter Control (FSA-Ctrl). In this architecture communication layer and control layer can manage the QoS policies. The communication layer is based on the Data Distribution Service (DDS), a standard proposed by Object Management Group (OMG). Control layer is derived from the Sensor Web Enablement (SWE) model proposed by Open Geospatial Consortium (OGC). Middleware components use messages queues to manage components QoS requirements. By means of QoS policies, control components can take important decisions about distributed questions, like components mobility or information redundancy detection.