Adoption of vehicular ad hoc networking protocols by networked robots

This paper focuses on the utilization of wireless networking in the robotics domain. Many researchers have already equipped their robots with wireless communication capabilities, stimulated by the observation that multi-robot systems tend to have several advantages over their single-robot counterparts. Typically, this integration of wireless communication is tackled in a quite pragmatic manner, only a few authors presented novel Robotic Ad Hoc Network (RANET) protocols that were designed specifically with robotic use cases in mind. This is in sharp contrast with the domain of vehicular ad hoc networks (VANET). This observation is the starting point of this paper. If the results of previous efforts focusing on VANET protocols could be reused in the RANET domain, this could lead to rapid progress in the field of networked robots. To investigate this possibility, this paper provides a thorough overview of the related work in the domain of robotic and vehicular ad hoc networks. Based on this information, an exhaustive list of requirements is defined for both types. It is concluded that the most significant difference lies in the fact that VANET protocols are oriented towards low throughput messaging, while RANET protocols have to support high throughput media streaming as well. Although not always with equal importance, all other defined requirements are valid for both protocols. This leads to the conclusion that cross-fertilization between them is an appealing approach for future RANET research. To support such developments, this paper concludes with the definition of an appropriate working plan

Classification of Routing Algorithms in Volatile Environment of Underwater Wireless Sensor Networks

The planet earth is basically a planet of water with less than 30% land mass available for humans to live on. However, the areas covered with water are important to mankind for the various resources which have been proven to be valuable. Such resources are gas, oil, marine products which can be used as food, and other minerals. In view of the vast area in which these resources can be found, a network of sensors is necessary so that they can be explored. However, sensor networks may not be helpful in the exploration of these resources if they do not have a sufficiently good routing mechanism. Over the past few decades, several methods for routing have been suggested to address the volatile environment in underwater communications. These continue researches; have enhanced the performance along with time. Meanwhile, there are still challenges to deal with for a better and efficient routing of data packets. Large end-to-end delays, high error channel rates, limited bandwidth, and the consumption of energy in sensor network are some such challenges. A comprehensive survey of the various routing methods for the partially connected underwater communication environment are presented in this paper

Part 1: acceptance test and administration of a farm of servers. Part 2: improving TCP performance in underwater wireless sensor networks

Dissertação de mestrado, Engenharia Informática, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2017Abstract 1 During the last decades, companies and organizations have focused on how to provide to the end-users or clients with web services or applications to make them more closer and involved to the activity. Therefore, many enterprises through their direction of the IT service, propose varieties of applications that allow to the stakeholders to perform what they need. The aim of this report is to present what the application integration job is and to report the missions that I have been able to carry out such as application integration, application qualification, and acceptance tests. This represents in total: - 19 qualified applications, - 33 administrated serversResumo 1 Ao longo das últimas décadas, as empresas e as organizações concentraram-se na forma de fornecer aos usuários finais ou clientes, serviços Web ou aplicativos para torná-los mais próximos e envolvidos na actividade. Portanto, muitas empresas através da sua direcção do serviço de Tecnólogia da Informação TI, propõem variedades de aplicativos que permitem às partes interessadas realizar o que necessitam. O objectivo deste relatório é apresentar o que é o trabalho de integração de aplicativos e as missões que fui capaz de executar, como a integração de aplicativos, a qualificação de aplicativos e testes de aceitação. Isto representa no total: - 19 aplicações qualificadas, - 33 servidores administradosAbstract 2 Underwater wireless sensor networks (UWSNs) are becoming popular due to their important role in different applications, such as offshore search and underwater monitoring. However, the data transmission in this underwater environment is impacted by various aspects such as bandwidth usage limitation, surrounding noise and large acoustic propagation delays. Therefore, communication itself is an outstanding challenge. The well-known traditional transmission control protocol (TCP), one of the most used transport protocol on the internet, is not suitable to enable this technology. Even though TCP variants for the wireless network are not foolproof in an underwater environment, their use could probably be more difficult in such a multi-hop communication system. We have chosen Newreno for our study. This variant is a modern implementation that includes the four congestion control algorithms. These algorithms have proved to be effective when it comes to terrestrial networks which could be a basis for our study. In addition, Newreno is known for its algorithm of recovery of several segments lost within the same sending window. In this dissertation, we have conducted a general study of UWSN technology and examined methods to improve TCP performance in a multi-hop UWSN. And then, we propose Underwater-Newreno (U-Newreno) our enhanced version of Newreno to improve TCP performance in UWSN. U-Newreno consists of two major modifications: controlling the maximum size of the congestion window and the adaptation of the round trip time (RTT) timeout. The results of simulations carried out with the Aquasim simulator show improvements of performances in terms of gain of: packets delivery Retransmission ratio of packets delivery.Resumo 2 As redes de sensores sem fio subaquáticos (Underwater Wireless Sensor Networks- UWSN) estão-se a tornar cada vez mais populares devido à sua importância em diferentes aplicações, como a pesquisa offshore e monitoramento subaquático. No entanto, a transmissão de dados neste ambiente subaquático sofre devido a vários factores, como a limitação do uso da largura de banda, o ruído envolvente e grandes atrasos de propagação acústica. Portanto, a comunicação é um desafio problemático. O familiar transmission control protocol (TCP) tradicional, um dos protocolos de transporte mais utilizados na internet, não é adequado para habilitar esta tecnologia. Mesmo que as variantes TCP para a rede sem fio não sejam infalíveis num ambiente subaquático, o seu uso provavelmente pode ser mais difícil num sistema de comunicação de múltiplos saltos. Nós escolhemos o Newreno para o nosso estudo. Esta variante é uma implementação moderna que inclui os quatro algoritmos de controle de congestionamento. Estes algoritmos demonstraram a sua eficácia em redes terrestres que poderiam ser uma base para o nosso estudo. Além disso, Newreno é conhecido pelo seu algoritmo de recuperação de vários segmentos perdidos dentro da mesma janela de envio. Nesta dissertação, realizamos um estudo geral da tecnologia UWSN e examinamos métodos para melhorar o desempenho do TCP num UWSN de vários saltos. E então, propomos a U-Newreno (Underwater-Newreno), a nossa versão melhorada do Newreno para melhorar o desempenho do TCP no UWSN. O U-Newreno consiste em duas modificações principais: controlar o tamanho máximo da janela de congestionamento e a adaptação do tempo limite “Round Trip Time”(RTT). Os resultados das simulações realizadas com o simulador Aquasim mostram melhorias nos desempenhos em termos de ganho de: • entrega de pacotes • Taxa de retransmissão da entrega de pacotes

Self-organizing Fast Routing Protocols for Underwater Acoustic Communications Networks

To address this problem, in this thesis we propose a cross-layer proactive routing initialization mechanism that does not require additional measurements and, at the same time, is energy efficient. Two routing protocols are proposed: Self-Organized Fast Routing Protocol for Radial Underwater Networks (SOFRP) for radial topology and Self-organized Proactive Routing Protocol for Non-uniformly Deployed Underwater Networks (SPRINT) for a randomly deployed network. SOFRP is based on the algorithm to recreate a radial topology with a gateway node, such that packets always use the shortest possible path from source to sink, thus minimizing consumed energy. Collisions are avoided as much as possible during the path initialization. The algorithm is suitable for 2D or 3D areas, and automatically adapts to a varying number of nodes. In SPRINT the routing path to the gateway is formed on the basis of the distance, measured by the signal strength received. The data sending node prefers to choose the neighbor node which is closest to it. It is designed to achieve high data throughput and low energy consumption of the nodes. There is a tradeoff between the throughput and the energy consumption: more distance needs more transmission energy, and more relay nodes (hops) to the destination node affects the throughput. Each hop increases the packet delay and decreases the throughput. Hence, energy consumption requires nearest nodes to be chosen as forwarding node whereas the throughput requires farthest node to be selected to minimize the number of hops. Fecha de lectura de Tesis Doctoral: 11 mayo 2020Underwater Wireless Sensor Networks (UWSNs) constitute an emerging technology for marine surveillance, natural disaster alert and environmental monitoring. Unlike terrestrial Wireless Sensor Networks (WSNs), electromagnetic waves cannot propagate more than few meters in water (high absorption rate). However, acoustic waves can travel long distances in underwater. Therefore, acoustic waves are preferred for underwater communications, but they travel very slow compare to EM waves (typical speed in water is 1500 m/s against 2x10^8 m/s for EM waves). This physical effect makes a high propagation delay and cannot be avoided, but the end-to-end packet delay it can be reduced. Routing delay is one of the major factors in end-to-end packet delay. In reactive routing protocols, when a packet arrives to a node, the node takes some time to select the node to which the data packet would be forwarded. We may reduce the routing delay for time-critical applications by using proactive routing protocols. Other two critical issues in UWSNs are determining the position of the nodes and time synchronization. Wireless sensor nodes need to determine the position of the surrounding nodes to select the next node in the path to reach the sink node. A Global Navigation Satellite System (GNSS) cannot be used because of the very short underwater range of the GNSS signal. Timestamping to estimate the distance is possible but the limited mobility of the UWSN nodes and variation in the propagation speed of the acoustic waves make the time synchronization a challenging task. For these reasons, terrestrial WSN protocols cannot be readily used for underwater acoustic networks

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Channel-aware routing for underwater wireless networks

Abstract-This paper presents a new cross layer routing protocol for underwater wireless sensor networks. The solution, termed CARP for Channel-aware Routing Protocol, exploits link quality information for cross layer relay determination. Nodes are selected as relays if they have a (recent) history of successful transmissions to their neighbors. CARP combines link quality with simple topology information (hop count), thus being able to route around connectivity voids and shadow zones. The protocol is also designed to take advantage of power control for selecting robust links. The performance of CARP has been evaluated through ns2-based simulations, and compared to the performance of two previously proposed routing protocols, namely, FBR and DBR. Our results show that CARP robust relay selection mechanism enables it to achieve throughput efficiency that is up to twice the throughput of FBR and almost three times that of DBR. CARP also obtains remarkable performance improvements over FBR and DBR with respect to end-to-end packet latency and energy consumption. Index Terms-Underwater acoustic networks, cross layer design, MAC and routing protocols

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Analysis of performance in Depth Based Routing for Underwater Wireless Sensor Networks

In the last decade, Underwater Wireless Sensor Networks (UWSNs) have been widely studied because of their peculiar aspects that distinguish them from common wireless terrestrial networks. In fact, most UWSNs use acoustic instead of radio-frequency based communications, and nodes are subject to high mobility caused by water currents. As a consequence, specialized routing algorithms have been developed to tackle this challenging scenario. Depth based Routing (DBR) is one of the first protocols that have been developed to this aim, and is still widely adopted in actual implementations of UWSNs. In this paper we propose a stochastic analysis that aims at evaluating the performance of UWSNs using DBR in terms of expected energy consumption and expected end-to-end delay. Under a set of assumptions, we give expressions for these performance indices that can be evaluated efficiently, and hence they can be adopted as the basis for optimizing the configuration parameters of the protocol

Desenvolupament, proves de camp i anàlisi de resultats en una xarxa de sensors

The objective of this master thesis is to describe the problems of the underwater acoustic sensor network and make some experiments. The experiments carried out try to characterize the communication in underwater environments in order to be able to develop underwater sensor networks. In the first chapter we describe the motivations, features of aquatic environment, the difficulties of underwater acoustic channels, and the open questions in mobile underwater sensor network design. In the second chapter we try to describe the experiments, show the results and try to explain these results. And finally in the third chapter we explain the conclusions and the further works of this master thesis