Application of publish-subscribe middleware to road traffic measurements visualization

Visualization of the effects of control measures is important for decision support in complex networks. The example in this article is a visualization system for road traffic measurements, such as intensity, density, waiting time and velocity, at junctions in networks controlled by traffic signals. The system was developed based on a layered implementation architecture, which has the advantage of abstracting lowlevel details during development, and using an object-oriented approach. In order to cope with the complexity of the system due to its distributed nature and real-time constraints, we decided to apply publish-subscribe middleware for components communication, which offers some important advantages, such as scalability, flexibility, and improved performance.