Reliability analysis of wireless sensor network for smart farming applications

Wireless Sensor Networks are subjected to some design constraints (e.g., processing capability, storage memory, energy consumption, fixed deployment, etc.) and to outdoor harsh conditions that deeply affect the network reliability. The aim of this work is to provide a deeper understanding about the way redundancy and node deployment affect the network reliability. In more detail, the paper analyzes the design and implementation of a wireless sensor network for low-power and low-cost applications and calculates its reliability considering the real environmental conditions and the real arrangement of the nodes deployed in the field. The reliability of the system has been evaluated by looking for both hardware failures and communication errors. A reliability prediction based on different handbooks has been carried out to estimate the failure rate of the nodes self-designed and self-developed to be used under harsh environments. Then, using the Fault Tree Analysis the real deployment of the nodes is taken into account considering the Wi-Fi coverage area and the possible communication link between nearby nodes. The findings show how different node arrangements provide significantly different reliability. The positioning is therefore essential in order to obtain maximum performance from a Wireless sensor network

Formal Availability Analysis using Theorem Proving

Availability analysis is used to assess the possible failures and their restoration process for a given system. This analysis involves the calculation of instantaneous and steady-state availabilities of the individual system components and the usage of this information along with the commonly used availability modeling techniques, such as Availability Block Diagrams (ABD) and Fault Trees (FTs) to determine the system-level availability. Traditionally, availability analyses are conducted using paper-and-pencil methods and simulation tools but they cannot ascertain absolute correctness due to their inaccuracy limitations. As a complementary approach, we propose to use the higher-order-logic theorem prover HOL4 to conduct the availability analysis of safety-critical systems. For this purpose, we present a higher-order-logic formalization of instantaneous and steady-state availability, ABD configurations and generic unavailability FT gates. For illustration purposes, these formalizations are utilized to conduct formal availability analysis of a satellite solar array, which is used as the main source of power for the Dong Fang Hong-3 (DFH-3) satellite.Comment: 16 pages. arXiv admin note: text overlap with arXiv:1505.0264

Precision Agriculture and Sensor Systems Applications in Colombia through 5G Networks

The growing global demand for food and the environmental impact caused by agriculture have made this activity increasingly dependent on electronics, information technology, and telecommunications technologies. In Colombia, agriculture is of great importance not only as a commercial activity, but also as a source of food and employment. However, the concept of smart agriculture has not been widely applied in this country, resulting in the high production of various types of crops due to the planting of large areas of land, rather than optimization of the processes involved in the activity. Due to its technical characteristics and the radio spectrum considered in its deployment, 5G can be seen as one of the technologies that could generate the greatest benefits for the Colombian agricultural sector, especially in the most remote rural areas, which currently lack mobile network coverage. This article provides an overview of the current 5G technology landscape in Colombia and presents examples of possible 5G/IoT applications that could be developed in Colombian fields. The results show that 5G could facilitate the implementation of the smart farm in Colombia, improving current production and efficiency. It is useful when designing 5G implementation plans and strategies, since it categorizes crops by regions and products. This is based on budget availability, population density, and regional development plans, among others.AUIP (Iberoamerican University Association for Postgraduate Studies)Spanish Government PGC2018-098813-B-C33UAL-FEDER 2020 UAL2020-TIC-A208

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

Formal Reliability Analysis of Wireless Sensor Network Data Transport Protocols using HOL

Abstract-In recent times, Wireless Sensor Networks (WSNs) have shown a great potential for monitoring physical or environmental conditions in a variety of safety and financialcritical applications, ranging from medicine to transportation and surveillance. Given the extreme conditions of most of the WSN environments, it is very important to make WSN communication resilient to network failures. Various data transport protocols have been proposed in the literature to serve this purpose. The reliability of these WSN data transport protocols is usually assessed by using Reliability Block Diagrams (RBDs). Traditionally, RBD-based reliability analyses of WSN data transport protocols is done using paper-and-pencil proofs or computer simulations, which cannot ascertain absolute correctness due to their inherent incompleteness. As a complementary approach, we propose to use the higher-order-logic theorem prover HOL to conduct the RBD-based reliability analysis of WSN data transport protocols. In particular, the paper provides a higher-order-logic formalization of series, parallel and parallel-series RBDs. These RBDs are then used to do the formal reliability analysis of the end-to-end (e2e) data transport mechanism, and the Event to Sink Reliable Transport (ESRT) and Reliable Multi-Segment Transport (RMST) data transport protocols

Reliability and lifetime modeling of wireless sensor nodes

The accuracy of system reliability analysis depends not only on system-level model construction, but also on realistic estimation of failure parameters at the component-level. In this paper, we model and evaluate the reliability and lifetime of a wireless sensor node under three typical working scenarios, contributing toward the accurate reliability analysis of wireless sensor network systems. According to the medium access control (MAC) protocols, the three working scenarios are defined based on the sensor node modes (sleep and active) and the mechanism of alternating between the modes. Reliability and lifetime of wireless sensor nodes under these three scenarios are illustrated and compared through numerical examples. © 2013 Elsevier Ltd. All rights reserved

Reliability modeling of wireless sensors

The accuracy of system reliability analysis depends on realistic estimation of failure parameters at the component-level. This paper models the reliability of wireless sensor nodes under three different scenarios, contributing toward reliability analysis of wireless sensor network systems. Under Scenario 1, a sensor node is kept activated and consumes constant energy throughout its lifetime. Under Scenario 2, a sensor node alternates between two modes: sleep mode and active mode. The duration of each mode is fixed. It consumes less power during the sleep mode than during the active mode. Under Scenario 3, a sensor node also alternates between sleep and active modes but the duration of each mode is not fixed. In particular, the duration of the active mode is bounded and follows a certain distribution. However, the time to activate the sensor node is fixed. Numerical example results show that sensor node working under Scenario 3 is the most reliable and offers longest lifetime among the three scenarios while Scenario 1 is the least reliable one. © 2013 IEEE