Design and analysis of adaptive hierarchical low-power long-range networks

A new phase of evolution of Machine-to-Machine (M2M) communication has started where vertical Internet of Things (IoT) deployments dedicated to a single application domain gradually change to multi-purpose IoT infrastructures that service different applications across multiple industries. New networking technologies are being deployed operating over sub-GHz frequency bands that enable multi-tenant connectivity over long distances and increase network capacity by enforcing low transmission rates to increase network capacity. Such networking technologies allow cloud-based platforms to be connected with large numbers of IoT devices deployed several kilometres from the edges of the network. Despite the rapid uptake of Long-power Wide-area Networks (LPWANs), it remains unclear how to organize the wireless sensor network in a scaleable and adaptive way. This paper introduces a hierarchical communication scheme that utilizes the new capabilities of Long-Range Wireless Sensor Networking technologies by combining them with broadly used 802.11.4-based low-range low-power technologies. The design of the hierarchical scheme is presented in detail along with the technical details on the implementation in real-world hardware platforms. A platform-agnostic software firmware is produced that is evaluated in real-world large-scale testbeds. The performance of the networking scheme is evaluated through a series of experimental scenarios that generate environments with varying channel quality, failing nodes, and mobile nodes. The performance is evaluated in terms of the overall time required to organize the network and setup a hierarchy, the energy consumption and the overall lifetime of the network, as well as the ability to adapt to channel failures. The experimental analysis indicate that the combination of long-range and short-range networking technologies can lead to scalable solutions that can service concurrently multiple applications

A Survey on Facilities for Experimental Internet of Things Research

International audienceThe initial vision of the Internet of Things (IoT) was of a world in which all physical objects are tagged and uniquelly identified by RFID transponders. However, the concept has grown into multiple dimensions, encompassing sensor networks able to provide real-world intelligence and goal-oriented collaboration of distributed smart objects via local networks or global interconnections such as the Internet. Despite significant technological advances, difficulties associated with the evaluation of IoT solutions under realistic conditions, in real world experimental deployments still hamper their maturation and significant roll out. In this article we identify requirements for the next generation of the IoT experimental facilities. While providing a taxonomy, we also survey currently available research testbeds, identify existing gaps and suggest new directions based on experience from recent efforts in this field

A smartwater metering deployment based on the fog computing paradigm

In this paper, we look into smart water metering infrastructures that enable continuous, on-demand and bidirectional data exchange between metering devices, water flow equipment, utilities and end-users. We focus on the design, development and deployment of such infrastructures as part of larger, smart city, infrastructures. Until now, such critical smart city infrastructures have been developed following a cloud-centric paradigm where all the data are collected and processed centrally using cloud services to create real business value. Cloud-centric approaches need to address several performance issues at all levels of the network, as massive metering datasets are transferred to distant machine clouds while respecting issues like security and data privacy. Our solution uses the fog computing paradigm to provide a system where the computational resources already available throughout the network infrastructure are utilized to facilitate greatly the analysis of fine-grained water consumption data collected by the smart meters, thus significantly reducing the overall load to network and cloud resources. Details of the system's design are presented along with a pilot deployment in a real-world environment. The performance of the system is evaluated in terms of network utilization and computational performance. Our findings indicate that the fog computing paradigm can be applied to a smart grid deployment to reduce effectively the data volume exchanged between the different layers of the architecture and provide better overall computational, security and privacy capabilities to the system

Contribuciones al establecimiento de una red global de sensores inalámbricos interconectados

Se ha considerado a este trabajo como un aporte al establecimiento de una red global de sensores donde los humanos (agentes inteligentes), y computadoras potentes interactúan con redes piloto de sensores inalámbricos, distinguiendo en la red global 3 subdominios: • Una red superior existente, donde los distintos nodos ejecutan las aplicaciones en potentes computadoras que pueden interconectarse vía Internet u otras redes globales. • Los dispositivos sensores que forman una red piloto y se comunican entre sí por medio inalámbrico. • Un portal de servidores, formado por nodos que controlan las redes piloto, y permiten la interacción entre los nodos de la red superior y los dispositivos de la WSN. Los temas a desarrollar en esta tesis son: •Modelado y simulación: La simulación es utilizada para evaluar sistemas desarrollados y a implementar en redes reales. La utilidad de los datos obtenidos depende puramente del realismo y la precisión de los modelos a implementar. Fundamentalmente se avanzan con simulaciones que simplifican la instalación de las WSNs. •Entorno de desarrollo de aplicaciones: Necesario para la corrida de las simulaciones como también desarrollo de las aplicaciones a ser instaladas en los nodos físicos existentes. •Alternativa de soporte de las WSN: la preexistencia de situaciones donde la prestación de servicios de transmisión de datos es sumamente ineficiente y provisto por una empresa de manera monopólica. Ciertas veces el servicio es inexistente en la locación del proyecto. Por ello se avanzó en la búsqueda de un soporte a la red de WSN no basada en la Red Digital Soporte de la prestadora en la región de desarrollo del trabajo.Facultad de Informátic

Distributed Algorithm Engineering

When one engineers distributed algorithms, some special characteristics arise that are different from conventional (sequential or parallel) computing paradigms. These characteristics include: the need for either a scalable real network environment or a platform supporting a simulated distributed environment; the need to incorporate asynchrony, where arbitraryasynchronyis hard, if not impossible, to implement; and the generation of “difficult ” input instances which is a particular challenge. In this work, we identifysome of the methodological issues required to address the above characteristics in distributed algorithm engineering and illustrate certain approaches to tackle them via case studies. Our discussion begins byaddressing the need of a simulation environment and how asynchronyis incorporated when experimenting with distributed algorithms. We then proceed bysuggesting two methods for generating difficult input instances for distributed experiments, namelya game-theoretic one and another based on simulations of adversarial arguments or lower bound proofs