Claudio Borean

On the performance of ZigBee Pro and ZigBee IP in IEEE 802.15.4 networks

The wide spread of smart embedded devices and the trend towards their inclusion in a unique Internet of Things are making urgent their full integration within the TCP/IP protocol stack. This paper considers ZigBee, a short-range radio communication standard for embedded devices, and compares two alternative protocol stacks, namely ZigBee Pro and ZigBee IP, developed for the integration of ZigBee in the so called Internet of Things. The performance evaluation is founded on experimental results achieved using two test-beds built to this purpose and is based on service reliability and latency as metrics.

Crowd Steering in Public Spaces: Approaches and Strategies

Smart phones and environmental sensors make it possible to dynamically monitor the positions and patterns of movements of people in urban areas and public spaces, identify or predict possible dangerous situations (e.g., overcrowded areas) or simply recognize the profitability of a different patterns of distribution and collective movements. In this article, we focus on the problem of using such technologies also to steer the movement of people in public and urban spaces, i.e., suggesting people where to move to eventually reach some desirable global configuration in terms of crowd distribution. In particular, we overview and motivate the general problem of crowd steering, identify the technologies that can be put into play, and the possible strategies to direct people movements. Following, we present the results of a set of simulations that we have performed to assess the effectiveness of two exemplary crowd steering strategies.

Urban Crowd Steering: An Overview

Smart phones and environmental sensors make it possible to dynamically monitor the positions and patterns of movements of people in urban areas and public spaces, identify or predict possible dangerous situations e.g., overcrowded areas or simply recognize the profitability of a different patterns of distribution and collective movements. In this overview paper, we focus on the problem of using such technologies also to steer the movement of people. In particular, this paper has the goal of motivating the general problem of crowd steering, identifying the technologies that can be put to play to enforce crowd steering strategies, and presenting the possible strategies that can be adopted to steer people movements, other than the key research challenges.

Heuristic approaches for a domestic energy management system

Abstract In the context of smart buildings, house energy consumption plays a significant role in the energy system. Since there are different billing rates, the aim of the smart grid system is to minimize the overall energy cost by appropriately selecting the best starting times for each household appliance. Further, the scheduler should guarantee that the instant energy request does not overcome the maximum threshold which depends on the customers contract. Although the maximum threshold is a constant, the instant energy consumption may possibly exceed this value, whenever is available some renewable source such as, for instance, solar energy. In this work, we consider the problem of scheduling smart home appliances within a given time horizon respecting the threshold on the energy peak consumption with the objective of minimizing the overall cost related to the average energy consumption of each appliance at each time instant. A hybrid heuristic based on a mixed integer programming formulation of the problem and a particle swarm optimization approach are proposed. Computational results, applying these approaches to real life data are provided and discussed.

Energy@home Leveraging ZigBee to Enable Smart Grid in Residential Environment

In this paper, the project called Energy@home is introduced. It is a new and innovative attempt to standardize the Smart Grid eco-system, providing use cases and standardization of the communication protocol within a Home Area Network (HAN). Energy@home has been started as an Italian collaborative project among different companies, founded by Electrolux, Enel, Indesit Company and Telecom Italia. The aim of the project was to develop a communication infrastructure that enables provision of “Value Added Services” based upon information exchange related to energy usage, energy consumption and energy tariffs in the HAN. Different technologies are supported, but the first integration among different devices has been developed using ZigBee: this technology offers green and global wireless standards connecting the widest range of devices to work together intelligently. After the release of Energy@home specification and the validation of it through a number of interoperability test events, the Energy@home project has moved from being a collaborative project into a non-profit association. The goal of the association is to promote technologies and services for the home energy efficiency and for the proactive participation of the end users. The Energy@home Association is open to any company and anyone who is wishing to contribute to its purposes and it is rapidly growing with the addition of new members.

Transparent Bandwidth Aggregation for Residential Access Networks

We propose, implement, and evaluate a bandwidth aggregation service for residential users that allows to improve the upload throughput of the asymmetric digital subscriber line connection by leveraging the unused bandwidth of neighboring users. The residential access gateway adopts the 802.11 radio interface to simultaneously serve the local home users and to share the broadband connectivity with neighboring access gateways. Differently from previous works, our aggregation scheme is transparent both for local users, who are not required to modify their applications or device drivers, and for neighboring users, who do not experience any meaningful performance degradation. To evaluate the achievable performance and tune the parameters driving the traffic balancing, we developed a fluid model that was shown experimentally to be very accurate. Our proposed scheme is amenable to efficient implementation on Linux networking stack. Indeed, we implemented it and tested in some realistic scenarios, showing an efficient exploitation of the whole available bandwidth, also for legacy cloud storage applications.

A Reputation-based Distributed District Scheduling Algorithm for Smart Grids

In this paper we develop and test a distributed algorithm providing Energy Consumption Schedules (ECS) in smart grids for a residential district. The goal is to achieve a given aggregate load profile. The NP-hard constrained optimization problem reduces to a distributed unconstrained formulation by means of Lagrangian Relaxation technique, and a meta-heuristic algorithm based on a Quantum inspired Particle Swarm with Levy flights. A centralized iterative reputation-reward mechanism is proposed for end-users to cooperate to avoid power peaks and reduce global overload, based on random distributions simulating human behaviors and penalties on the effective ECS differing from the suggested ECS. Numerical results show the protocols effectiveness.

Distributed Consensus Agreement of a Real Swarm Robotic System

This paper presents a real robotic swarm system deployed on a circuit. Each agent has constant speed and is able to detect a frontal crash, switching its direction with a given turning-back probability. Physical and logical description of the autonomous system is provided, and both a real testing and numerical experiments are presented, investigating convergence and times. Accordingly, a mathematical model assures also analytically the convergence of the swarming system to a consensus configuration, where all the robots drive with the same orientation along the closed circuit.

Software Design and Implementation for a DEMO on ZigBee Information Delivery

The paper introduces the software design and implementation for a DEMO on ZigBee Information Delivery, which is an unreleased ZigBee Telecom Application Profile chaired by Telecom Italia. The DEMO is fulfilled by using a fixed gateway connected to the operator network for configuring and managing the information nodes, a mobile device that will operate as the mobile node in the network, and ZigBee information nodes that will be compliant to the new ZigBee Telco Application profile.