140 research outputs found
Low-power wide-area networks : design goals, architecture, suitability to use cases and research challenges
Previous survey articles on Low-Powered Wide-Area Networks (LPWANs) lack a systematic analysis of the design goals of LPWAN and the design decisions adopted by various commercially available and emerging LPWAN technologies, and no study has analysed how their design decisions impact their ability to meet design goals. Assessing a technology's ability to meet design goals is essential in determining suitable technologies for a given application. To address these gaps, we have analysed six prominent design goals and identified the design decisions used to meet each goal in the eight LPWAN technologies, ranging from technical consideration to business model, and determined which specific technique in a design decision will help meet each goal to the greatest extent. System architecture and specifications are presented for those LPWAN solutions, and their ability to meet each design goal is evaluated. We outline seventeen use cases across twelve domains that require large low power network infrastructure and prioritise each design goal's importance to those applications as Low, Moderate, or High. Using these priorities and each technology's suitability for meeting design goals, we suggest appropriate LPWAN technologies for each use case. Finally, a number of research challenges are presented for current and future technologies. © 2013 IEEE
Adaptive Square-Shaped Trajectory-Based Service Location Protocol in Wireless Sensor Networks
In this paper we propose an adaptive square-shaped trajectory (ASST)-based service location method to ensure load scalability in wireless sensor networks. This first establishes a square-shaped trajectory over the nodes that surround a target point computed by the hash function and any user can access it, using the hash. Both the width and the size of the trajectory are dynamically adjustable, depending on the number of queries made to the service information on the trajectory. The number of sensor nodes on the trajectory varies in proportion to the changing trajectory shape, allowing high loads to be distributed around the hot spot area
Parallel Processing Method for Airborne Laser Scanning Data Using a PC Cluster and a Virtual Grid
In this study, a parallel processing method using a PC cluster and a virtual grid is proposed for the fast processing of enormous amounts of airborne laser scanning (ALS) data. The method creates a raster digital surface model (DSM) by interpolating point data with inverse distance weighting (IDW), and produces a digital terrain model (DTM) by local minimum filtering of the DSM. To make a consistent comparison of performance between sequential and parallel processing approaches, the means of dealing with boundary data and of selecting interpolation centers were controlled for each processing node in parallel approach. To test the speedup, efficiency and linearity of the proposed algorithm, actual ALS data up to 134 million points were processed with a PC cluster consisting of one master node and eight slave nodes. The results showed that parallel processing provides better performance when the computational overhead, the number of processors, and the data size become large. It was verified that the proposed algorithm is a linear time operation and that the products obtained by parallel processing are identical to those produced by sequential processing
An Efficient Routing Algorithm for Mesh-Hypercube (M-H) Networks
Proceedings of the International Conference on Parallel and Distributed Processing
Techniques and Applications (PDPTA'08, ISBN Set # 1-60132-084-1),
Editors: Hamid R. Arabnia and Youngsong Mun, 2008.This paper presents an efficient routing algorithm for the Mesh-Hypercube (M-H) network. The M-H network is one of the new interconnection networking techniques use to build high performance parallel computers. The combination of M-H networks offers high connectivity among multiple nodes, fault-tolerance, and load scalability. However, the performance of M-H networks may degrade significantly in the presence of frequent link or node failures. When a link or node failure occurs, neither the hardware schemes nor point to point and multistage routing algorithms can be used without adding extra links. This paper presents an efficient single bit store and forward (SBSF) routing algorithm for MH network that based on the round robin scheduling algorithm. Simulation and numerical results suggest that the proposed routing algorithm improves the overall performance of M-H network by both reducing the transmission delay and increasing the total data throughput even in the presence of faulty nodes.http://www.world-academy-of-science.org
Low-Power Wide-Area Networks: A Broad Overview of its Different Aspects
Low-power wide-area networks (LPWANs) are gaining popularity in the research community due to their low power consumption, low cost, and wide geographical coverage. LPWAN technologies complement and outperform short-range and traditional cellular wireless technologies in a variety of applications, including smart city development, machine-to-machine (M2M) communications, healthcare, intelligent transportation, industrial applications, climate-smart agriculture, and asset tracking. This review paper discusses the design objectives and the methodologies used by LPWAN to provide extensive coverage for low-power devices. We also explore how the presented LPWAN architecture employs various topologies such as star and mesh. We examine many current and emerging LPWAN technologies, as well as their system architectures and standards, and evaluate their ability to meet each design objective. In addition, the possible coexistence of LPWAN with other technologies, combining the best attributes to provide an optimum solution is also explored and reported in the current overview. Following that, a comparison of various LPWAN technologies is performed and their market opportunities are also investigated. Furthermore, an analysis of various LPWAN use cases is performed, highlighting their benefits and drawbacks. This aids in the selection of the best LPWAN technology for various applications. Before concluding the work, the open research issues, and challenges in designing LPWAN are presented.publishedVersio
Evaluation of Scalability and Communication in MMOGs
Massively Multiplayer Online Games (MMOGs) can involve millions of synchronous players scattered across the world and participating with each other within a single shared game. One of the most significant issues in MMOGs is scalability and it is impact on the responsiveness and the quality of the game. In this paper, we propose a new architecture to increase the scalability without affecting the responsiveness of the game, using a hybrid Peer-to-Peer system. This mechanism consists of central servers to control and manage the game state, as well as super-peer and clone-super-peer to control and manage sub-networks of nodes sharing common regions of the game world. We use the OPNET Modeler to simulate the system and compare the results with client/server system to show the difference in delay and traffic received for various applications such as remote login, database, HTTP, and FTP sessions which are all part of an MMOG system. We use four scenarios for each system to evaluate the scalability of the system with different number of peers (i.e.125, 250, 500, and 1000 peers). The results show that the hybrid P2P system is more scalable for MMOGs when compared with client/server system
- …