The Bus Goes Wireless: Routing-Free Data Collection with QoS Guarantees in Sensor Networks

Abstract—We present the low-power wireless bus (LWB), a new communication paradigm for QoS-aware data collection in lowpower sensor networks. The LWB maps all communication onto network floods by using Glossy, an efficient flooding architecture for wireless sensor networks. Therefore, unlike current solutions, the LWB requires no information of the network topology, and inherently supports networks with mobile nodes and multiple data sinks. A LWB prototype implemented in Contiki guarantees bounded end-to-end communication delay and duplicate-free, inorder packet delivery—key QoS requirements in many control and mission-critical applications. Experiments on two testbeds demonstrate that the LWB prototype outperforms state-of-theart data collection and link layer protocols, in terms of reliability and energy efficiency. For instance, we measure an average radio duty cycle of 1.69 % and an overall data yield of 99.97 % in a typical data collection scenario with 85 sensor nodes on Twist. I

A cross layer framework for WLANs: joint radio propagation and MAC protocol

This paper proposes a cross-layer design (CLD) framework called channel-aware buffer unit multiple access (C-BUMA) for improving wireless local area network (WLAN) performance. In the framework, the radio propagation (i.e. PHY layer) is combined with the medium access control (MAC) protocol for packet transmissions. By sharing channel information with the MAC protocol, the approach reduced unnecessary packet transmissions and hence improved system performance. Through performance evaluation, we demonstrate that our CLD can significantly improve network throughput and packet delay. The proposed C-BUMA is simple and can easily be implemented in 802.11 networks without changing hardware infrastructure and no additional costs. In this paper we describe C-BUMA and present two algorithms for the implementation of the framework

A Source-Initiated On-Demand Routing Algorithm Based on the Thorup-Zwick Theory for Mobile Wireless Sensor Networks

The unreliability and dynamics of mobile wireless sensor networks make it hard to perform end-to-end communications. This paper presents a novel source-initiated on-demand routing mechanism for efficient data transmission in mobile wireless sensor networks. It explores the Thorup-Zwick theory to achieve source-initiated on-demand routing with time efficiency. It is able to find out shortest routing path between source and target in a network and transfer data in linear time. The algorithm is easy to be implemented and performed in resource-constrained mobile wireless sensor networks. We also evaluate the approach by analyzing its cost in detail. It can be seen that the approach is efficient to support data transmission in mobile wireless sensor networks

A Review of Quality of Service Issues in Internet of Vehicles (IoV)

Recent years compared to the current scenario, the explosive growth of devices connected and controlled by internet is the major significance of internet of things (iot). One such big example is automotive industry. This industry has the potential to become an iot champion among other industries and fuel the iot cloud services adoption among car owners and walkers alike. Vehicles are progressively being associated with the internet of things which empower them to give universal access to data to drivers and travellers while moving. As the connectivity of vehicles keeps increasing in numbers, traditional concepts of vehicles has to be introduced with new layers which includes versatile data transfer among vehicles, consistency, security, toughness, humans and roadside frameworks of vehicular systems shall be taken into consideration. In this unique situation, the first idea of vehicular ad-hoc networks(vanets) is being changed into another idea called internet of vehicles(iov).the advent of iot has changed the traditional vehicular networks in to intelligent vehicular networks called internet of vehicles. Each entity in iov is connected to the internet. In iov, each vehicle is responsible for transmitting and receiving the information. In an environment where vehicles are mobile and at the same time exchanging information to ensure safe driving on the roads and to minimize road accidents. It is very necessary to provide better services within the limited accessibilities. Hence qos plays a vital role in iov. This paper addresses the qos challenges and its significance in iov. Also, this paper also discusses the measurement parameters that could deliberately effect the performance of iov

Software-defined routing protocol for mobile cognitive radio networks : a cross-layer perspective

The growing demand for wireless applications, combined with inefficient spectrum use, necessitates developing a new wireless communication paradigm that focuses on dynamic spectrum access rather than the fixed spectrum using cognitive radio technology. The unlicensed user, known as secondary user or cognitive user, uses cognitive radio technology to grow opportunistic communication over licensed spectrum bands and improve spectrum management performance. The routing protocol in Cognitive Radio Networks (CRNs) serves as a communication backbone, allowing data packets to transfer between cognitive user nodes through multiple paths and channels. However, the problem of routing in CRNs is to create a robust-stable route over higher channel availability. The previously developed protocols missed opportunities to exploit the time-variant channel estimation technique, which selects the best route using the cross-layer routing decision engine to track the adverse impact of cognitive user mobility and primary user activity. This study aims to construct a robust routing path while limiting interference with primary user activity, delaying routing, and maximizing routing throughput. Here, a new routing framework is created in this study to explore new extended routing functions and features from the lower layers (Physical layer and Data Link layer) feedback to improve routing performance. Then, the link-oriented channel availability and channel quality have been developed based on two reliable metrics, which are channel availability probability and channel quality, to estimate and select a channel that maximizes link-throughput. Furthermore, this study proposes a novel cross layer routing protocol, namely, the Software-Defined Routing Protocol. It is a cross-layer method to combine the lower layer (Physical layer and Data Link layer) sensing derived from the channel estimation model. It periodically updates the routing table for optimal route decision making. The output simulation of the channel estimation method has shown that it has produced a powerful channel selection strategy to maximize the average rate of link throughput and achieved a channel estimate under the time-variant effect. Extensive simulation experiments have been performed to evaluate the proposed protocol in compression with the existing benchmark protocols, namely, dual diversity cognitive Ad-hoc routing protocol and cognitive Ad-hoc on-demand distance vector. The proposed protocol outperforms the benchmarks, resulting in increasing the packet delivery ratio by around (11.89%-12.80%), reducing delay by around (2.74%-4.05%), reducing overhead by around (14.31%-18.36%), and increasing throughput by around (23.94%-28.35%). The software-defined routing protocol, however, lacks the ability to determine the better idle channel at high-speed node mobility. In conclusion, the cross-layer routing protocol successfully achieves high routing performance in finding a robust route, selecting high channel stability, and reducing the probability of interference with primary users for continued communication

AVISS: Aplicación Adaptativa de Streaming de Vídeo

En este trabajo presentamos AVISS (Adaptive VIdeo-Streaming Application), una aplicación para la transmisión adaptativa de streaming de vídeo en redes móviles ad-hoc (MANET, Mobile Ad-hoc Networks). AVISS pretende ofrecer una mejor Calidad de Experiencia (QoE, Quality of Experience) al usuario final mediante la auto-adaptación a las condiciones cambiantes de operación de la red. Para medir la calidad del vídeo recibido, también se ha definido una nueva métrica llamada Calidad del GoP (QoG, Quality of GoP). Esta métrica se calcula en el destino final en tiempo real y depende de la cantidad y tipo de cuadros de vídeo recibidos por cada GoP (Group of Pictures) transmitido, por lo que está relacionada con la QoE que el usuario final podría percibir. AVISS ha sido implementado utilizando la versión de RTP/RTCP del simulador de redes NCTUns, y sus prestaciones se han evaluado bajo diferentes condiciones de operación en redes MANET, reconocidas por ser altamente dinámicas.------ In this paper we present AVISS (Adaptive VIdeo-Streaming Application), an adaptive Client-Server application for video-streaming over Mobile Ad-hoc NETworks (MANETs). AVISS pretends to offer a better Quality of Experience (QoE) to the end user of the video-streaming system by adapting itself to time-varying operating conditions of the network. In order to measure the quality of the received video, we also define a new metric called Quality of GoP (QoG), which is easy to measure at the destination node, it does not require the original transmitted video as reference and it is related to the QoE end-user could perceive. As a proof of concept, AVISS has been implemented over a modified version of the RTP/RTCP implementation included with the NCTU network simulator (NCTUns) and we have evaluated its performance on simulated MANETs under several different operating conditions.Peer ReviewedPostprint (published version

Hop-by-hop routing in wireless mesh networks with bandwidth guarantees

Wireless Mesh Network (WMN) has become an important edge network to provide Internet access to remote areas and wireless connections in a metropolitan scale. In this paper, we study the problem of identifying the maximum available bandwidth path, a fundamental issue in supporting quality-of-service in WMNs. Due to interference among links, bandwidth, a well-known bottleneck metric in wired networks, is neither concave nor additive in wireless networks. We propose a new path weight which captures the available path bandwidth information. We formally prove that our hop-by-hop routing protocol based on the new path weight satisfies the consistency and loop-freeness requirements. The consistency property guarantees that each node makes a proper packet forwarding decision, so that a data packet does traverse over the intended path. Our extensive simulation experiments also show that our proposed path weight outperforms existing path metrics in identifying high-throughput paths. © 2012 IEEE.published_or_final_versio