D02.04 -communication Network Design (rel.2) Information and Communication Technologies Communication Network Design (rel. 2) -d02.04 Communication Network Design (rel. 2) -d02.04

SUMMARY In this report, divided into 4 chapters, we report the final advances on WP2 and in particular on the task 3.2, " Communication network design ". It corresponds to an extended version of Deliverable 2.1 since it includes some novel contributes, namely Section 2.3. Chapter one introduces the developed arguments and presents parts of the literature review. Chapter two is devoted to network topology design, and offers recent studies on the influence of network topologies on the performance of distributed systems, i.e. systems constituted by many interacting units. Concerning this topic, the paper [9] analyses the performance of the consensus algorithm, which is largely proposed as an efficient and low complexity tool for distributed control, estimation and optimization. The optimal topology for this algorithm, yielding fastest convergence time, is proposed. This topo-logy is described by the de Bruijn graphs. In [27, 15] the properties of the Cayley graphs (again in relation with the consensus algorithm) are analyzed. These graphs are often used as a simple paradigm of geometric graphs, namely graphs in which the nodes are deployed in a geometric space. For this kind of graph topologies quadratic type performance indexes are often considered. Those performance indexes come into the picture when applying consensus algorithms to distributed estimation or control and yield completely different evaluation of the possible choices of the network topologies. In [35, 34] we extend the result for Cayley graphs taking into consideration a special class of geometric graphs, characterized by four purely geometric parameters. The extension is done for the particular class of reversible Markov chains due to the strong analogy they show with resistive electrical networks. Chapter three deals with control applications, and more generally with real-time applications running over wireless sensor networks (WSNs). These systems require the design of dedicated routing protocols and control strategies to cope with the potential random delays and packet losses due to the wireless nature of the WSNs. In this chapter we then address this problem from two points of view. In the first we focus on the design of special routing strategies, namely Unicast Path Diversity (UDP) and Directed Staged Flooding (DSF), that are specifically designed for real-time application: in fact they can trade off lower end-to-end delays with higher packet loss. These two strategies, however, cannot completely remove delays randomness or packet losses. Therefore, for linear dynamical systems, we designed opportune time-varying Kalman filters that compensate …