Quality of Information in Wireless Sensor Networks: A Survey 1 (Completed paper)

Abstract: In Wireless Sensor Networks (WSNs) the operating conditions and/or user requirements are often desired to be evolvable, whether driven by changes of the monitored parameters or WSN properties of configuration, structure, communication capacities, node density, and energy among many others. While considering evolvability, delivering the required information with the specified quality (accuracy, timeliness, reliability etc) defined by the user constitutes a key objective of WSNs. Most existing research efforts handle fluctuations of operation conditions in order to deliver information with the highest possible specified quality. In this paper, we take these aspects into consideration and survey existing work on Quality of Information (QoI). As a contribution, we categorize WSN information into a set of abstract classes for generality across varied application types. Our survey shows that currently QoI is usually addressed in isolation by focusing on discrete data processing operations/building blocks such as raw data collection, in-network processing (compression, aggregation), information transport and sink operations for decision making. This survey comprehensively explains the different views of QoI on attributes, metrics and WSN functional operations mapped with existing approaches. The survey also forms the basis for specifying needed QoI research issues

Enabling IoT ecosystems through platform interoperability

Today, the Internet of Things (IoT) comprises vertically oriented platforms for things. Developers who want to use them need to negotiate access individually and adapt to the platform-specific API and information models. Having to perform these actions for each platform often outweighs the possible gains from adapting applications to multiple platforms. This fragmentation of the IoT and the missing interoperability result in high entry barriers for developers and prevent the emergence of broadly accepted IoT ecosystems. The BIG IoT (Bridging the Interoperability Gap of the IoT) project aims to ignite an IoT ecosystem as part of the European Platforms Initiative. As part of the project, researchers have devised an IoT ecosystem architecture. It employs five interoperability patterns that enable cross-platform interoperability and can help establish successful IoT ecosystems.Peer ReviewedPostprint (author's final draft

Eine verallgemeinerte Broadcast-Methode für mobile Ad-Hoc-Netze

Broadcasting is a major communication primitive required by many applications and protocols in Mobile Ad Hoc Networks (MANETs). It is frequently deployed for content distribution, service discovery or advertisement, and sensor data dissemination. Broadcast protocols are also a fundamental building block to realize principal middleware functionalities such as replication, group management and consensus. Broadcasting in MANETs has therefore been an active area of research recently. Most of the research conducted on broadcasting in MANETs has primarily focused only on carefully selected application and evaluation scenarios. Consequently, the developed broadcasting schemes do not yield good performance for other scenarios. Different comparative studies show that the existing broadcasting techniques are tailored to only one class of MANETs with respect to node density and node mobility, and are unfortunately not likely to operate well in other classes. Node spatial distribution is a key issue for the performance of broadcast protocols, since it determines the connectivity of the MANET. Our survey of potential MANET application scenarios shows a wide range of possible node spatial distributions and node mobilities. This leads to that a MANET generally shows a continuously changing network connectivity over space and time. Therefore, a generalized solution for broadcasting that accounts for the requirements of the various applications and adapts to the heterogeneous and evolving node spatial distribution and mobility is a major contribution. In this thesis, we present hypergossiping, a novel generalized broadcasting technique for MANETs. Hypergossiping integrates two adaptive schemes and efficiently switches between them depending on local node density. The first scheme is adaptive gossiping, which distributes messages within connected parts of the MANET. We adapted gossiping as follows. First, we established an analytical model for gossiping through adopting the SI mathematical model from the epidemiology. Then, we used the model to adapt the gossiping forwarding probability to local node density. As a result, we provide a simple analytical expression that nodes use to set the appropriate forwarding probability depending on the current number of neighbors. Simulation results showed that adaptive gossiping efficiently propagates messages within a network partition independent of the node spatial distribution and node mobility in that network partition. The second scheme is a broadcast repetition method, which detects partition joins using an efficient and localized heuristic and efficiently repeats the needed broadcasts upon detection of a partition join. Our approach is mobility-assisted since it exploits the mobility of nodes to efficiently deliver messages in frequently partitioned scenarios. We defined mobility metrics that simplify the design of mobility-assisted concepts, and used some of them to design a mobility-aware buffering strategy, which can significantly reduce the buffer overhead of hypergossiping. Simulation results in the standard network simulator ns-2 show that hypergossiping outperforms all existing strategies. Hypergossiping significantly increases the delivery ratio for a broad range of MANETs with respect to node density, node mobility and network load while providing high efficiency and scalability.Broadcast ist eine wichtige Kommunikationsprimitive, die für die Realisierung zahlreicher Anwendungen und Protokolle in Mobilen Ad-Hoc-Netzen (MANETs) essentiell ist. Broadcast ist ein grundsätzlicher Baustein, um Middleware-Funktionalitäten wie Replikation, Gruppenkommunikation und Konsensus zu realisieren. Außerdem wird Broadcast dazu verwendet, Ressourcen zu finden und bereitzustellen, und Informationen wie beispielsweise Warnungen oder Meldungen auf alle Netzwerk-Knoten zu verteilen. Broadcast ist folglich ein sehr aktiver Forschungsbereich in MANETs in den letzten Jahren geworden. Die meisten, existierenden MANET-Broadcast-Methoden sind hauptsächlich für sorgfältig ausgewählte Anwendungsszenarien entwickelt worden. Infolgedessen sind diese Methoden nur für spezifische Szenarien optimiert. Unterschiedliche, vergleichende Studien haben gezeigt, daß die existierenden Verfahren sich nur für eine Klasse von MANET-Szenarien bezüglich der Kontendichte und Knotenmobilität eignen. Vorherige Arbeiten haben gezeigt, daß die räumliche Knotenverteilung einen klaren Einfluß auf die Performanz von MANET-Broadcast-Protokollen hat. Aufgrund möglicher Knotenmobilität weisen MANETs eine sehr stark variierende, räumliche Knotenverteilung und folglich eine ständig variierende Konnektivität über Zeit und Raum auf. Die Vielfalt der möglichen Anwendungsszenarien für MANETs erhöhen diese Dynamik und weiten außerdem die Bandbreite der möglichen Netzwerkgrößen und folglich die Raumverteilung der Knoten aus. Deshalb ist eine verallgemeinerte, adaptive Broadcast-Methode erforderlich, die mit den ständig variierenden MANET-Eigenschaften und Anwendungsanforderungen ohne explizite Vorkonfiguration funktioniert. In dieser Arbeit präsentieren wir Hypergossiping, eine neue, verallgemeinerte Broadcast-Methode für MANETs. Hypergossiping integriert zwei adaptive Methoden und wechselt zwischen ihnen in Abhängigkeit von der Knotendichte. Die erste Methode ist adaptives Gossiping, welches Nachrichten innerhalb einer Netzwerkpartition effizient verteilt. Wir adaptieren Gossiping an die lokale Knotendichte wie folgt: Zuerst entwickeln wir ein analytisches Modell für Gossiping durch das Anpassen des mathematischen SI-Modells aus der Epidemiologie. Dann benutzten wir das Modell, um die optimale Gossiping-Weiterleitungswahrscheinlichkeit in Abhängigkeit von der lokalen Knotendichte zu bestimmen. Infolgedessen stellen wir einen einfachen analytischen Ausdruck zur Verfügung, welchen die Knoten verwenden, um die passende Weiterleitungswahrscheinlichkeit in Abhängigkeit von der aktuellen Anzahl der Nachbarn zu wählen. Die Simulationsergebnisse zeigen, daß das adaptive Gossiping Nachrichten innerhalb einer Netzwerkpartition unabhängig von der Knotendichte und Knotenmobilität zuverlässig und effizient verteilt. Die zweite Methode ist die effiziente Broadcast-Wiederholung bei Partitionsfusionierungen. Unser Ansatz besteht aus einer effizienten Heuristik zur Erkennung der Partitionsfusionierungen und aus einem Protokoll zur Wiederholung des Gossipings von benötigten Nachrichten. Hierfür speichern die Knoten die Broadcast-Nachrichten in einem lokalen Puffer zwischen. Für die Broadcast-Wiederholung spielt die Mobilität auf einer großen Zeitskala eine Schlüsselrolle, deshalb definieren wir neue Mobilitätsmetriken, die wir verwenden, um eine effiziente mobilitätsbewußte Pufferung für Hypergossiping zu entwerfen. Simulationen in ns-2 haben gezeigt, daß Hypergossiping alle vorhandenen Broadcast-Methoden an Performanz übertrifft. Hypergossiping vergrößert die Zustellungsrate auf effiziente und skalierbare Weise und für eine breite Reihe von MANETs in Bezug auf die Knotendichte, Knotenmobilität und Netzlast

Cooperative robots and sensor networks 2014

This book is the second volume on Cooperative Robots and Sensor Networks. The primary objective of this book is to provide an up-to-date reference for cutting-edge studies and research trends related to mobile robots and wireless sensor networks, and in particular for the coupling between them. Indeed, mobile robots and wireless sensor networks have enabled great potentials and a large space for ubiquitous and pervasive applications. Robotics and wireless sensor networks have mostly been considered as separate research fields and little work has investigated the marriage between these two technologies. However, these two technologies share several features, enable common cyber-physical applications and provide complementary support to each other. The book consists of ten chapters, organized into four parts. The first part of the book presents three chapters related to localization of mobile robots using wireless sensor networks. Two chapters presented new solutions based Extended Kalman Filter and Particle Filter for localizing the robots using range measurements with the sensor network. The third chapter presents a survey on mobility-assisted localization techniques in wireless sensor networks. The second part of the book deals with cooperative robots and sensor networks applications. One chapter presents a comprehensive overview of major applications coupling between robots and sensor networks and provides real-world examples of their cooperation. Two other chapters present applications for underwater robots and sensor networks

Cooperative robots and sensor networks

Mobile robots and Wireless Sensor Networks (WSNs) have enabled great potentials and a large space for ubiquitous and pervasive applications. Robotics and WSNs have mostly been considered as separate research fields and little work has investigated the marriage between these two technologies. However, these two technologies share several features, enable common cyber-physical applications and provide complementary support to each other. The primary objective of book is to provide a reference for cutting-edge studies and research trends pertaining to robotics and sensor networks, and in particular for the coupling between them. The book consists of five chapters. The first chapter presents a cooperation strategy for teams of multiple autonomous vehicles to solve the rendezvous problem. The second chapter is motivated by the need to improve existing solutions that deal with connectivity prediction, and proposed a genetic machine learning approach for link-quality prediction. The third chapter presents an architecture for indoor navigation using an Android smartphone for guiding a variety of users, from sighted to the visually impaired, to their intended destination. In chapter four, the authors deal with accurate prediction modeling of ocean currents for underwater glider navigation. In chapter five, the authors discuss the challenges and limitations of RSS-based localization mechanisms and propose, EasyLoc, an autonomous and practical RSS-based localization technique that satisfies ease of deployment and implementation.  

Gossiping: Adaptive and Reliable Broadcasting in

Abstract. Given the frequent topology changes in Mobile Ad Hoc Networks (MANET), the choice of appropriate broadcasting techniques is crucial to ensure reliable delivery of messages. The spreading of broadcast messages has a strong similarity with the spreading of infectious diseases. Applying epidemiological models to broadcasting allows an easy evaluation of such strategies depending on the MANET characteristics, e.g. the node density. In this paper, we develop an epidemic model for gossiping, which is a flooding-based probabilistic broadcasting technique. We analytically investigate the impact of node density and forwarding probability on the quality of gossiping. The result of our investigation is to enable mobile nodes for dynamically adapting their forwarding probability depending on the local node density. Simulation results in ns-2 show the reliability, efficiency and scalability of adaptive gossiping

Cooperative Robots and Sensor Networks

X, 98 p. 51 illus.online resource

MAP++:support for map-based WSN modeling and design with OMNeT++.

Wireless Sensor Networks (WSN) are receiving growing attention in the research community. As simulation is a frequently used to test and validate the different approaches, the flexibility of the simulation environments to support the varied WSN schema is desirable. The multitude works regarding WSN in general [7, 8], and OMNeT++ [1, 2, 5, 6] in particular, confirm the rising interest in providing the simulation environment for WSNs. As map based design is most appropriate for WSN[3], unfortunately, no project within the WSN community investigates map paradigms for simulations. The map paradigm builds on the region principle and therefore, provides excellent modeling primitives for WSNs. Global maps are created for the sake of network monitoring [3, 10] or of event detection [3, 9