90 research outputs found

    A Comprehensive Analysis of Literature Reported Mac and Phy Enhancements of Zigbee and its Alliances

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    Wireless communication is one of the most required technologies by the common man. The strength of this technology is rigorously progressing towards several novel directions in establishing personal wireless networks mounted over on low power consuming systems. The cutting-edge communication technologies like bluetooth, WIFI and ZigBee significantly play a prime role to cater the basic needs of any individual. ZigBee is one such evolutionary technology steadily getting its popularity in establishing personal wireless networks which is built on small and low-power digital radios. Zigbee defines the physical and MAC layers built on IEEE standard. This paper presents a comprehensive survey of literature reported MAC and PHY enhancements of ZigBee and its contemporary technologies with respect to performance, power consumption, scheduling, resource management and timing and address binding. The work also discusses on the areas of ZigBee MAC and PHY towards their design for specific applications

    A Comprehensive Survey on the Cyber-Security of Smart Grids: Cyber-Attacks, Detection, Countermeasure Techniques, and Future Directions

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    One of the significant challenges that smart grid networks face is cyber-security. Several studies have been conducted to highlight those security challenges. However, the majority of these surveys classify attacks based on the security requirements, confidentiality, integrity, and availability, without taking into consideration the accountability requirement. In addition, some of these surveys focused on the Transmission Control Protocol/Internet Protocol (TCP/IP) model, which does not differentiate between the application, session, and presentation and the data link and physical layers of the Open System Interconnection (OSI) model. In this survey paper, we provide a classification of attacks based on the OSI model and discuss in more detail the cyber-attacks that can target the different layers of smart grid networks communication. We also propose new classifications for the detection and countermeasure techniques and describe existing techniques under each category. Finally, we discuss challenges and future research directions

    Performance Analysis Of Data-Driven Algorithms In Detecting Intrusions On Smart Grid

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    The traditional power grid is no longer a practical solution for power delivery due to several shortcomings, including chronic blackouts, energy storage issues, high cost of assets, and high carbon emissions. Therefore, there is a serious need for better, cheaper, and cleaner power grid technology that addresses the limitations of traditional power grids. A smart grid is a holistic solution to these issues that consists of a variety of operations and energy measures. This technology can deliver energy to end-users through a two-way flow of communication. It is expected to generate reliable, efficient, and clean power by integrating multiple technologies. It promises reliability, improved functionality, and economical means of power transmission and distribution. This technology also decreases greenhouse emissions by transferring clean, affordable, and efficient energy to users. Smart grid provides several benefits, such as increasing grid resilience, self-healing, and improving system performance. Despite these benefits, this network has been the target of a number of cyber-attacks that violate the availability, integrity, confidentiality, and accountability of the network. For instance, in 2021, a cyber-attack targeted a U.S. power system that shut down the power grid, leaving approximately 100,000 people without power. Another threat on U.S. Smart Grids happened in March 2018 which targeted multiple nuclear power plants and water equipment. These instances represent the obvious reasons why a high level of security approaches is needed in Smart Grids to detect and mitigate sophisticated cyber-attacks. For this purpose, the US National Electric Sector Cybersecurity Organization and the Department of Energy have joined their efforts with other federal agencies, including the Cybersecurity for Energy Delivery Systems and the Federal Energy Regulatory Commission, to investigate the security risks of smart grid networks. Their investigation shows that smart grid requires reliable solutions to defend and prevent cyber-attacks and vulnerability issues. This investigation also shows that with the emerging technologies, including 5G and 6G, smart grid may become more vulnerable to multistage cyber-attacks. A number of studies have been done to identify, detect, and investigate the vulnerabilities of smart grid networks. However, the existing techniques have fundamental limitations, such as low detection rates, high rates of false positives, high rates of misdetection, data poisoning, data quality and processing, lack of scalability, and issues regarding handling huge volumes of data. Therefore, these techniques cannot ensure safe, efficient, and dependable communication for smart grid networks. Therefore, the goal of this dissertation is to investigate the efficiency of machine learning in detecting cyber-attacks on smart grids. The proposed methods are based on supervised, unsupervised machine and deep learning, reinforcement learning, and online learning models. These models have to be trained, tested, and validated, using a reliable dataset. In this dissertation, CICDDoS 2019 was used to train, test, and validate the efficiency of the proposed models. The results show that, for supervised machine learning models, the ensemble models outperform other traditional models. Among the deep learning models, densely neural network family provides satisfactory results for detecting and classifying intrusions on smart grid. Among unsupervised models, variational auto-encoder, provides the highest performance compared to the other unsupervised models. In reinforcement learning, the proposed Capsule Q-learning provides higher detection and lower misdetection rates, compared to the other model in literature. In online learning, the Online Sequential Euclidean Distance Routing Capsule Network model provides significantly better results in detecting intrusion attacks on smart grid, compared to the other deep online models

    Performance Enhancement Mechanism of IEEE 802.11AH Machine Communication System

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    As the Internet gets more populated and the number of devices increase dramatically, demanding connectivity anytime, anywhere and for everything, the urge for a novel concept is raised. Consequently, Internet of Things (IoT) is introduced to shed a light on the vision of the future Internet with tremendous amount of "things" interconnected to each other while utilizing various technologies for different applications. As a wide range of wireless technologies are developed and are extensively used worldwide, IEEE 802.11 working group for WLAN standards is developing a new amendment referred as IEEE 802.11AH targeting mainly the IoT based applications. The new amendment has inherited many characteristics from the legacy IEEE 802.11 while benefiting from new enhanced features defined specifically for IoT and Machine to Machine communications (M2M) systems. Ultimately, IEEE 802.11AH which has been defined to operate in sub-1 GHz band, is expected to support high number of simultaneous connections up to 6000 devices for a 1 km coverage range. This thesis implements some of the enhanced features for IEEE 802.11AH and conducts the corresponding evaluation based on a developed simulator. The aforementioned simulator has been compared to a Markov chain based analytical model, developed in this research. The results have shown that the developed system level simulator is following the results from the modeled network with high accuracy. The developed system level simulator has been used in performance evaluation of the IEEE 802.11AH main features like the restricted access window (RAW) and sectorization schemes in the case of single and multiple APs deployments scenarios. It is concluded that the implementation of these features, help to improve IEEE 802.11AH overall performance. The performance measures considered in this evaluation are throughput, energy efficiency and average delay in sending successful packets, respectively. Moreover, for resolving the coverage requirements there is a trade-off in using single AP or multi AP configuration. Implementing more APs results in more network capacity while causing additional interference to the network. The RAW and sectorization mechanisms can fortunately reduce this interference by minimizing the hidden node probability and mitigating against the overlapping BSS resulting problems

    Developments of 5G Technology

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    This technology is the future of current LTE technology which would be a boost to the future of wireless and computer networks, as the speeds would be way higher than the current LTE networks, which will push the technology to a new level. This technology will make the radio channels to support data access speeds up to 10 Gb/s which will turn the bandwidth radio channels as WiFi. Comparing it with other LTE technology\u27s it has high speed and capacity, support interactive multimedia, voice, internet and its data rate is 1 Gbps which makes it faster than other LTE’s . This is much more effective than other technology’s due to its advanced billing interfaces. This paper provides detail explanation of 5G technology, its architecture, challenges, advantages and disadvantages, issues and ends with future of 5G technology

    The 5G era of mobile networks: a comprehensive study of the related technologies accompanied by an experimentation framework

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    Οι συνεχώς αυξανόμενες απαιτήσεις από τα δίκτυα κινητών επικοινωνιών για τη παροχή καλύτερων υπηρεσιών και τη διασύνδεση όλων και περισσότερων συσκευών, ωθούν τη κοινότητα του κλάδου στην ανάπτυξη νέων μεθόδων και τεχνολογιών οργάνωσης των δικτύων προκειμένου να αντιμετωπιστεί αποτελεσματικά αυτή η πρόκληση. Δεδομένου ότι η παρούσα τεχνολογία έχει φτάσει στα όρια της από άποψη ικανότητας διαχείρισης της κίνησης, απαιτείται η ανάπτυξη ενός νέου πλαισίου λειτουργίας το οποίο θα μπορεί να ανταποκριθεί αποτελεσματικά στις νέες συνθήκες που διαμορφώνονται από τη τηλεπικοινωνιακή αγορά. Η 5 η γενιά των δικτύων κινητών επικοινωνιών (5G) αποσκοπεί στην επίλυση ακριβώς αυτού του ζητήματος, μέσα από την ανάπτυξη ενός νέου μοντέλου λειτουργίας. Το μοντέλο αυτό αναδιαρθρώνοντας εκ βάθρων τον τρόπο λειτουργίας του δικτύου σε όλα τα επίπεδα, σχηματίζει ένα νέο οικοσύστημα δικτυακών υποδομών και λειτουργιών το οποίο επιτρέπει τη παροχή στους χρήστες υπηρεσιών υψηλού επιπέδου, προσαρμοσμένες στις εκάστοτε ανάγκες τους. Στα πλαίσια της παρούσας εργασίας μελετήθηκαν εκτενώς οι θεμελιώδεις αρχές και οι κυριότερες τεχνολογίες που διέπουν τη λειτουργία ενός δικτύου νέας γενιάς καθ’ όλο το μήκος του. Ξεκινώντας από τις καινοτομίες που αφορούν τη δομή των 5G δικτύων σε επίπεδο αρχιτεκτονικής, η ανάλυση επεκτείνεται με μία προσέγγιση από κάτω προς τα πάνω· στα επίπεδα εκπομπής και πρόσβασης στο δίκτυο (C-RAN & MAC), στους μηχανισμούς που είναι υπεύθυνοι για παροχή των λειτουργιών και υπηρεσιών του δικτύου (NFV), ενώ εν συνεχεία γίνεται αναφορά στο νέο μοντέλο δρομολόγησης και διαχείρισης της κίνησης συνολικά στο δίκτυο (SDN) και σε επόμενο στάδιο παρουσιάζεται η τεχνολογία που αφορά την ικανότητα παροχής διακριτών υπηρεσιών στους χρήστες (E2E Slicing). Ακόμα, παρουσιάζονται ορισμένοι χαρακτηριστικοί δείκτες και μετρικές που σχετίζονται με τη προτυποποίηση των τεχνολογιών του δικτύου καθώς και όλες οι τρέχουσες εξελίξεις που αφορούν την ανάπτυξη του 5G στην Ευρώπη. Στη συνέχεια παρουσιάζονται τα δεδομένα του πειράματος που διεξήχθη για τους σκοπούς της εργασίας και αφορά αφενός τη μοντελοποίηση ενός υφιστάμενου δικτύου με βάση τα νέα πρότυπα του 5G και αφετέρου την αξιολόγηση της απόδοσης του με βάση ορισμένα σενάρια σχετικά με τη τοπολογία και το πλήθος των δεδομένων που ανταλλάσσονται κάθε στιγμή στο δίκτυο. Η εξέταση των παραμέτρων αποδοτικότητας εστιάζει στην ικανότητα του ONOS SDN Controller να διαχειρίζεται τη κίνηση των δεδομένων όταν προκύπτουν ορισμένα συμβάντα που επηρεάζουν την αρχική δομή του δικτύου. Ως προς τα αποτελέσματα των μετρήσεων που διεξάγονται, παρόλο που φαίνεται το θετικό αντίκτυπο που θα έχει η ενσωμάτωση των νέων τεχνολογιών στην απόδοση των δικτύων κινητών επικοινωνιών, υπάρχουν ακόμα ορισμένα επιμέρους ανοικτά ζητήματα τα οποία χρήζουν περαιτέρω έρευνας από τη πλευρά των μελών της τηλεπικοινωνιακής κοινότητας ώστε να μην υποσκαφθεί τελικά το αρχικό όραμα της καθολικής λειτουργίας όλων των κινητών συσκευών υπό μία ενιαία ομπρέλα.The ever-increasing demand from mobile communications networks for the provision of better services and interconnection of more devices is pushing the industry's community to develop new network organization methods and technologies in order to effectively address this challenge. As the current technology has reached its limits in terms of traffic management capability, it is necessary to develop a new operating framework that can effectively respond to the new conditions created by the telecommunications market. The 5th generation of mobile communication networks (5G) aims to solve this exact issue by developing a new operating model. This model, by thoroughly restructuring the way the network operates at all levels, forms a new ecosystem of network infrastructures and functions that enables the provision of high-level services to users, tailored to their particular needs. The fundamental principles and key technologies that govern the operation of a new generation network throughout its entire length were extensively studied in the context of this paper. Starting with the innovations regarding the structure of 5G networks at the architectural level, the analysis extends to a bottom-up approach: from the broadcast and access levels to the network (C-RAN & MAC) to the mechanisms responsible for delivering the network's functions and services (NFV). Then, the new network-based routing and traffic management (SDN) model is introduced, and the technology for providing distinctive services to users (E2E Slicing) is presented. Furthermore, some characteristic indicators and metrics related to the standardization of the network's technologies are presented, as well as all the current developments related to the development of 5G in Europe. Then, the data of the experiment carried out for the purposes of the paper is presented. On the one hand, this data concerns the modeling of an existing network based on the new 5G standards and, on the other hand, the evaluation of its performance based on some scenarios regarding the topology and the amount of data exchanged at any time on the network. The examination of the efficiency parameters focuses on the ability of the ONOS SDN controller to manage the traffic of the data when certain events affecting the original network structure occur. In terms of the results of the measurements being carried out, although the positive impact of the incorporation of new technologies on the performance of mobile communications networks appears to be positive, there are still some individual open issues that need further research by members of the telecommunications community in order for the original vision of the universal operation of all mobile devices under one single umbrella not to be ultimately undermined

    Building a test bed for simulation analysis for the internet of things

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    Mestrado com dupla diplomação com a Universidade Tecnológica e Federal do ParanáThe Internet of Things (IoT) enables the mix between the physical and informational world. Physical objects will be able to see, hear, think together, share information and coordinate decisions, without human interference in a variety of domains. To enable this vision of IoT in large scale is expected of the equipment to be low-cost, mobile, power efficient, computational constrained, and wireless communication enabled. This project performs an extensive overview of the state-of-the-art in communication technologies for IoT, simulation theory and tools. It also describes test bed for IoT simulation and its implementation. The simulation was built with Castalia Simulator (i.e. Wireless Sensor Networks (WSN) network) and INET framework (i.e. IP network), both extends OMNeT++ features. There are two independent networks that communicate through files and exchange information about source, destination, payload and simulation time. Analyzing the outputs is possible to assure that the routing protocol that is provided in the Castalia Simulator does not provide any advantage in terms of packets loss, packets reception or energy consumption.A Internet das Coisas (IoT) permite a mistura entre o mundo físico e informacional. Objetos físicos serão capazes de ver, ouvir, pensar juntos, compartilhar informações e coordenar decisões, sem interferência humana em uma variedade de domínios. Para permitir essa visão de IoT em larga escala, espera-se que o equipamento seja de baixo custo, móvel, eficiente em termos de energia, com restrições computacionais e possibilite a comunicação sem fio. Este projeto faz uma extensa visão geral do estado da arte em tecnologias de comunicação para IoT, teoria de simulação e ferramentas. Também descreve o banco de testes para simulação de IoT e sua implementação. A simulação foi construída com o Simulador Castalia (ou seja, rede WSN) e o framework INET (ou seja, rede IP), ambos estendem os recursos do OMNeT ++. Existem duas redes independentes que se comunicam através de arquivos e trocam informações sobre origem, destino, carga útil e tempo de simulação. Analisando os resultados é possível garantir que o protocolo de roteamento que é fornecido no Simulador Castalia não oferece qualquer vantagem em termos de quebra de pacotes, recepção de pacotes ou consumo de energia

    Smart Wireless Sensor Networks

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    The recent development of communication and sensor technology results in the growth of a new attractive and challenging area - wireless sensor networks (WSNs). A wireless sensor network which consists of a large number of sensor nodes is deployed in environmental fields to serve various applications. Facilitated with the ability of wireless communication and intelligent computation, these nodes become smart sensors which do not only perceive ambient physical parameters but also be able to process information, cooperate with each other and self-organize into the network. These new features assist the sensor nodes as well as the network to operate more efficiently in terms of both data acquisition and energy consumption. Special purposes of the applications require design and operation of WSNs different from conventional networks such as the internet. The network design must take into account of the objectives of specific applications. The nature of deployed environment must be considered. The limited of sensor nodes� resources such as memory, computational ability, communication bandwidth and energy source are the challenges in network design. A smart wireless sensor network must be able to deal with these constraints as well as to guarantee the connectivity, coverage, reliability and security of network's operation for a maximized lifetime. This book discusses various aspects of designing such smart wireless sensor networks. Main topics includes: design methodologies, network protocols and algorithms, quality of service management, coverage optimization, time synchronization and security techniques for sensor networks

    Contributions to IEEE 802.11-based long range communications

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    The most essential part of the Internet of Things (IoT) infrastructure is the wireless communication system that acts as a bridge for the delivery of data and control messages between the connected things and the Internet. Since the conception of the IoT, a large number of promising applications and technologies have been developed, which will change different aspects in our daily life. However, the existing wireless technologies lack the ability to support a huge amount of data exchange from many battery-driven devices, spread over a wide area. In order to support the IoT paradigm, IEEE 802.11ah is an Internet of Things enabling technology, where the efficient management of thousands of devices is a key function. This is one of the most promising and appealing standards, which aims to bridge the gap between traditional mobile networks and the demands of the IoT. To this aim, IEEE 802.11ah provides the Restricted Access Window (RAW) mechanism, which reduces contention by enabling transmissions for small groups of stations. Optimal grouping of RAW stations requires an evaluation of many possible configurations. In this thesis, we first discuss the main PHY and MAC layer amendments proposed for IEEE 802.11ah. Furthermore, we investigate the operability of IEEE 802.11ah as a backhaul link to connect devices over possibly long distances. Additionally, we compare the aforementioned standard with previous notable IEEE 802.11 amendments (i.e. IEEE 802.11n and IEEE 802.11ac) in terms of throughput (with and without frame aggregation) by utilizing the most robust modulation schemes. The results show an improved performance of IEEE 802.11ah (in terms of power received at long range while experiencing different packet error rates) as compared to previous IEEE 802.11 standards. Additionally, we expose the capabilities of future IEEE 802.11ah in supporting different IoT applications. In addition, we provide a brief overview of the technology contenders that are competing to cover the IoT communications framework. Numerical results are presented showing how the future IEEE 802.11ah specification offers the features required by IoT communications, thus putting forward IEEE 802.11ah as a technology to cater the needs of the Internet of Things paradigm. Finally, we propose an analytical model (named e-model) that provides an evaluation of the RAW onfiguration performance, allowing a fast adaptation of RAW grouping policies, in accordance to varying channel conditions. We base the e-model in known saturation models, which we adapted to include the IEEE 802.11ah’s PHY and MAC layer modifications and to support different bit rate and packet sizes. As a proof of concept, we use the proposed model to compare the performance of different grouping strategies,showing that the e-model is a useful analysis tool in RAW-enabled scenarios. We validate the model with existing IEEE 802.11ah implementation for ns-3.La clave del concepto Internet de las cosas (IoT) es que utiliza un sistema de comunicación inalámbrica, el cual actúa como puente para la entrega de datos y mensajes de control entre las "cosas" conectadas y el Internet. Desde la concepción del IoT, se han desarrollado gran cantidad de aplicaciones y tecnologías prometedoras que cambiarán distintos aspectos de nuestra vida diaria.Sin embargo, las tecnologías de redes computacionales inalámbricas existentes carecen de la capacidad de soportar las características del IoT, como las grandes cantidades de envío y recepción de datos desde múltiples dispositivos distribuidos en un área amplia, donde los dispositivos IoT funcionan con baterías. Para respaldar el paradigma del IoT, IEEE 802.11ah, la cual es una tecnología habilitadora del Internet de las cosas, para el cual la gestión eficiente de miles de dispositivos es una función clave. IEEE 802.11ah es uno de los estándares más prometedores y atractivos, desde su concepción orientada para IoT, su objetivo principal es cerrar la brecha entre las redes móviles tradicionales y la demandada por el IoT. Con este objetivo en mente, IEEE 802.11ah incluye entre sus características especificas el mecanismo de ventana de acceso restringido (RAW, por sus siglas en ingles), el cual define un nuevo período de acceso al canal libre de contención, reduciendo la misma al permitir transmisiones para pequeños grupos de estaciones. Nótese que para obtener una agrupación óptima de estaciones RAW, se requiere una evaluación de las distintas configuraciones posibles. En esta tesis, primero discutimos las principales mejoras de las capas PHY y MAC propuestas para IEEE 802.11ah. Además, investigamos la operatividad de IEEE 802.11ah como enlace de backhaul para conectar dispositivos a distancias largas. También, comparamos el estándar antes mencionado con las notables especificaciones IEEE 802.11 anteriores (es decir, IEEE 802.11n y IEEE 802.11ac), en términos de rendimiento (incluyendo y excluyendo la agregación de tramas de datos) y utilizando los esquemas de modulación más robustos. Los resultados muestran mejores resultados en cuanto al rendimiento de IEEE 802.11ah (en términos de potencia recibida a largo alcance, mientras se experimentan diferentes tasas de error de paquetes de datos) en comparación con los estándares IEEE 802.11 anteriores.Además, exponemos las capacidades de IEEE 802.11ah para admitir diferentes aplicaciones de IoT. A su vez, proporcionamos una descripción general de los competidores tecnológicos, los cuales contienden para cubrir el marco de comunicaciones IoT. También se presentan resultados numéricos que muestran cómo la especificación IEEE 802.11ah ofrece las características requeridas por las comunicaciones IoT, presentando así a IEEE 802.11ah como una tecnología que puede satisfacer las necesidades del paradigma de Internet de las cosas.Finalmente, proponemos un modelo analítico (denominado e-model) que proporciona una evaluación del rendimiento utilizando la característica RAW con múltiples configuraciones, el cual permite una rápida adaptación de las políticas de agrupación RAW, de acuerdo con las diferentes condiciones del canal de comunicación. Basamos el e-model en modelos de saturación conocidos, que adaptamos para incluir las modificaciones de la capa MAC y PHY de IEEE 802.11ah y para poder admitir diferentes velocidades de transmisión de datos y tamaños de paquetes. Como prueba de concepto, utilizamos el modelo propuesto para comparar el desempeño de diferentes estrategias de agrupación, mostrando que el e-model es una herramienta de análisis útil en escenarios habilitados para RAW. Cabe mencionar que también validamos el modelo con la implementación IEEE 802.11ah existente para ns-3
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