Wide Area Network Connectivity Research Articles

5G- Analysis and Characteristics in Comparison with Previous Generations

This paper explores the architecture and remarkable advantages of 5G technology in the current industry of wireless communication. The paper covers details of the recently developed 5th generation of networks and how its benefits overpower its drawbacks, majorly being its impact on health and environment. This study helps understanding 5G and highlights how this recent advancement has better chances of helping with wide area network connectivity, latency, economic growth, enhanced security features etc. While advancements in the cellular network technology continue to be one of the most important developments in the economic, telecom and healthcare sector among many others, many common beliefs about 5G which can be listed as its “drawbacks” have been brought to people’s attention recently, and with proper facts and studies, it can be easily proved how 5G, till this date, has no significant harm to any area, and simply has a few complexities which are natural with any advancement in technology. The paper covers the characteristics of the 5G network, and addresses common misconceptions and concerns surrounding health, security, and infrastructure.

Sublessor: A Cost-Saving Internet Transit Mechanism for Cooperative MEC Providers in Industrial Internet of Things

Mobile edge computing (MEC) is becoming increasingly popular due to its remarkable computing capacities in close proximity to end users or devices. With the widespread use of Industrial Internet of Things, more and more cloud service providers move their services to the edge of the network for a better quality of service and become MEC providers. These MEC providers require to rent wide area network (WAN) connections to transfer industrial data, which is a considerable expense. In this article, we propose a framework called <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Sublessor</i> to reduce the WAN transmission cost for a group of cooperative MEC providers. The key idea of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Sublessor</i> is allowing some specific MEC providers to act as Internet transit brokers, transmitting not only their own network traffic but also the traffic of their partners under a reasonable reselling price. This article formulates the problem as a mixed integer programming and finds the most suitable broker number and corresponding reselling price without damaging the profit of both brokers and partners by a deep-reinforcement-learning-based algorithm. Experimental results show that our algorithm can significantly reduce the traffic transmission cost by up to 35%.

Falcon: Fair and Efficient Online File Transfer Optimization

Research networks provide high-speed wide-area network connectivity between research and education institutions to facilitate large-scale data transfers. However, scalability issues of legacy transfer applications such as scp and FTP hinder the effective utilization of these networks. Although researchers extended the legacy transfer applications to increase their performance by exploiting I/O and network parallelism, these solutions necessitate users to fine-tune parallelism level, a task that is challenging even for experienced users due to the dynamic nature of networks. In this paper, we propose an online optimization algorithm, Falcon, to tune the degree of parallelism for file transfers to maximize transfer throughput while keeping system overhead at a minimum. As research networks are shared infrastructures, we introduce a game theory-inspired novel utility function to evaluate the performance of various parallelism levels such that competing transfers are guaranteed to converge to a fair and stable solution. We assessed the performance of Falcon in isolated and production high-speed networks and found that it can discover optimal transfer parallelism in as little as 20 seconds and outperform the state-of-the-art solutions by more than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$2\times$</tex-math></inline-formula> . Moreover, Falcon is guaranteed to converge to Nash Equilibrium when multiple transfers compete for the same resources with the help of its game theory-inspired utility function. Finally, we demonstrate that Falcon can also be used as a central transfer scheduler to speed up convergence time, increase stability, and enforce system/user-level resource limitations in shared networks.

Medium Access Control Techniques for Massive Machine-Type Communications in Cellular IoT Networks

A key component of the Internet of things (IoT) ecosystem is wide-area network connectivity, for which cellular network technologies are a promising option through their support of massive machine-type communications (mMTC). However, numerous devices transmitting sporadically small data packets in a highly synchronized way can generate overload on the radio access network. This situation leads to a shortage of resources, especially those associated with the random access procedure for contention, control, and data transmission, causing preamble collision, control message blocking, and data collision. As a result, mMTC traffic can jeopardize the provisioning of quality of service (QoS) to end-devices, decrease the network efficiency, and increase access latency and device energy consumption. This paper proposes medium access control (MAC) techniques for addressing problems related to the support of mMTC in cellularnetworks. First, a solution for allocating control resources with QoS provisioning and access differentiation is provided, including a resource management model, a scheduling algorithm, and a message prioritization policy. Second, a mechanism for reducing data collisions is also proposed. This solution comprises a protocol in which every device with scheduled retransmission uses a probabilistic policy to decide whether to retransmit, a novel method at the device to estimate the number of nodes trying random access, and two different retransmission policies employing this estimation. Results show that the proposals support QoS, decrease access latency, decrease the device energy consumption, and increase resource utilization under massive random access.&#x0D;

Long-Range Wide Area Network (LoRa-WAN) Connectivity and Range Evaluation in a Rural Setting

Long-Range Wide Area Network (LoRa-WAN) Connectivity and Range Evaluation in a Rural Setting

Self-Sufficient Sensor Node Embedding 2D Visible Light Positioning through a Solar Cell Module

Nowadays, indoor positioning (IP) is a relevant aspect in several scenarios within the Internet of Things (IoT) framework, e.g., Industry 4.0, Smart City and Smart Factory, in order to track, amongst others, the position of vehicles, people or goods. This paper presents the realization and testing of a low power sensor node equipped with long range wide area network (LoRaWAN) connectivity and providing 2D Visible Light Positioning (VLP) features. Three modulated LED (light emitting diodes) sources, the same as the ones commonly employed in indoor environments, are used. The localization feature is attained from the received light intensities performing optical channel estimation and lateration directly on the target to be localized, equipped with a low-power microcontroller. Moreover, the node exploits a solar cell, both as optical receiver and energy harvester, provisioning energy from the artificial lights used for positioning, thus realizing an innovative solution for self-sufficient indoor localization. The tests performed in a ~1 m2 area reveal accurate positioning results with error lower than 5 cm and energy self-sufficiency even in case of radio transmissions every 10 min, which are compliant with quasi-real time monitoring tasks.

Data Backup Approach using Software-defined Wide Area Network

Over the past several years, the traditional approaches of managing and utilizing hybrid Wide Area Network (WAN) connections, between sites across geographical regions, have posed many challenges to enterprises. Software-Defined Wide Area Network (SD-WAN) has emerged as a new paradigm that can overcome the traditional WAN challenges like the lack of visibility for WAN bandwidth utilization and the inefficient usage of expensive WAN resources. The flexibility and agility brought to WAN by applying the SD-WAN paradigm helped to improve the efficiency of bandwidth utilization and to address the surge of bandwidth demands. The SD-WAN capabilities become essential for meeting the heavy inter-data center's traffic exchange required for business continuity and disaster recovery operations. In this paper, a data backup approach is introduced using SD-WAN that makes the network centrally programmable. This will leverage the ability to make fine-grained traffic engineering for different data flows over WAN to optimize the bandwidth utilization of the expensive WAN resources by balancing the traffic load across network links between data centers and to minimize the time required to transfer backup data to disaster recovery sites. The proposed approach proved its efficiency according to the bandwidth utilization if it is compared to the other related works.

Experimental Evaluation of Desktop Operating Systems Networking Performance

The rapid advancement of network, communication and Internet technology resulted with always-on, always-connected, device-independent and remote online working, business, education and entertainment environment. Consequently, users are searching for solutions and technologies that enable fast and reliable wide area network connection and the typical solution is through using personal computers connected with ethernet cable to network equipment and infrastructure that supports gigabit ethernet connection. Besides the complex network infrastructure that can influence performance, the bottleneck can also be caused by insufficient hardware, operating system and software resources on clients’ machines. Therefore, in this paper a networking performance evaluation of three globally most common and most used versions of Windows operating systems; namely Windows 7TM, Windows 8.1TM and Windows 10TM, on two identical computer systems, is conducted. Networking performance measurements are performed with three different benchmarks: namely iPerf, D-ITG and NetStress. Performance evaluation results showed that a newer versions of an operating system bring certain networking performance improvements but by sacrificing other performances.

Solar+ Optimizer: A Model Predictive Control Optimization Platform for Grid Responsive Building Microgrids

With the falling costs of solar arrays and battery storage and reduced reliability of the grid due to natural disasters, small-scale local generation and storage resources are beginning to proliferate. However, very few software options exist for integrated control of building loads, batteries and other distributed energy resources. The available software solutions on the market can force customers to adopt one particular ecosystem of products, thus limiting consumer choice, and are often incapable of operating independently of the grid during blackouts. In this paper, we present the “Solar+ Optimizer” (SPO), a control platform that provides demand flexibility, resiliency and reduced utility bills, built using open-source software. SPO employs Model Predictive Control (MPC) to produce real time optimal control strategies for the building loads and the distributed energy resources on site. SPO is designed to be vendor-agnostic, protocol-independent and resilient to loss of wide-area network connectivity. The software was evaluated in a real convenience store in northern California with on-site solar generation, battery storage and control of HVAC and commercial refrigeration loads. Preliminary tests showed price responsiveness of the building and cost savings of more than 10% in energy costs alone.

An Efficient Polar Coding Scheme for Uplink Data Transmission in Narrowband Internet of Things Systems

Narrowband Internet of Things (NB-IoT) is an emerging IoT cellular-based wireless technology that builds based on the existing LTE standard to extend its network coverage suited for Low Power Wide Area Network (LPWAN) connectivity. In the NB-IoT system, LTE turbo codes and Cyclic Redundancy Check (CRC) codes are adopted as the main channel coding technique for Narrowband Physical Uplink Shared Channel (NPUSCH). However, turbo codes require iterative decoding algorithm at the expense of high computation complexity of decoding hence is crucial to achieving the LPWAN requirement of NB-IoT systems. Polar codes are best suited in this regard due to its capacity approaching and complexity reduction in short block length code. In this paper, we proposed an efficient polar coding technique using the Belief Propagation (BP) decoding algorithm for uplink data transmission on the NPUSCH channel. Furthermore, the BP algorithm is incorporated with the CRC stoppage criterion to decrease the number of decoding iteration and reduce computational complexity. In this scheme, single-tone numerology of NPUSCH using 3.75 kHz and 15 kHz subcarrier spacing is adopted. Then, the encoded data is generated with different NPUSCH resources. The theoretical formulation and simulation demonstrate that the proposed scheme provides better error rate performance over the adopted LTE turbo codes and other polar decoding algorithms while reducing the computational complexity.

Gap analysis on open data interconnectivity for disaster risk research

ABSTRACTOpen data strategies are being adopted in disaster-related data particularly because of the need to provide information on global targets and indicators for implementation of the Sendai Framework for Disaster Risk Reduction 2015–2030. In all phases of disaster risk management including forecasting, emergency response and post-disaster reconstruction, the need for interconnected multidisciplinary open data for collaborative reporting as well as study and analysis are apparent, in order to determine disaster impact data in timely and reportable manner. The extraordinary progress in computing and information technology in the past decade, such as broad local and wide-area network connectivity (e.g. Internet), high-performance computing, service and cloud computing, big data methods and mobile devices, provides the technical foundation for connecting open data to support disaster risk research. A new generation of disaster data infrastructure based on interconnected open data is evolving rapidly. There are two levels in the conceptual model of Linked Open Data for Global Disaster Risk Research (LODGD) Working Group of the Committee on Data for Science and Technology (CODATA), which is the Committee on Data of the International Council for Science (ICSU): data characterization and data connection. In data characterization, the knowledge about disaster taxonomy and data dependency on disaster events requires specific scientific study as it aims to understand and present the correlation between specific disaster events and scientific data through the integration of literature analysis and semantic knowledge discovery. Data connection concepts deal with technical methods to connect distributed data resources identified by data characterization of disaster type. In the science community, interconnected open data for disaster risk impact assessment are beginning to influence how disaster data are shared, and this will need to extend data coverage and provide better ways of utilizing data across domains where innovation and integration are now necessarily needed.

Software-Defined WAN via Open APIs

Cloud applications require the ability to customize bandwidth and network policies for desired wide area network (WAN) connections. Unfortunately, currently widely used virtual private network is difficult to achieve such customization where sophisticated manual configurations and operator expertise are required. Software-defined network (SDN) creates the opportunities to provide this ability. In this paper, we design Grace, a SDN-based system to provide diverse connections with flexible bandwidth and customized policies, implementing WAN as a service. Our contributions can be listed as follows: 1) We introduce open APIs for customers by abstracting WAN connections based on connection types, bandwidth, latency sensitivity, and policy-related information; 2) We develop an effective conflict detection algorithm considering both resource reservation and safety guarantee; 3) We propose a linear programming -based bandwidth algorithm for latency-sensitive connections by dynamic scheduling of time and bandwidth, and design a pricing scheme for various connection demands to address the case that network cannot fulfill all the connection requests. A prototype implementation and extensive evaluations show that Grace provides the ability to customize WAN connections without policy conflicts, allocates required bandwidth optimally, translates them into low-level configurations for underlying network devices, and successfully deploys WAN in a short time.

Cost-Efficient Placement of Communication Connections for Transmission Line Monitoring

For overhead transmission line monitoring, wireless sensor networks offer a low-cost solution to connect sensors on towers with the control center. However, these networks cannot meet stringent quality of service (QoS) requirements, in terms of packet delivery ratio and delay. Also, it is necessary to ensure robustness such that data can be delivered when a tower fails. In view of the QoS and robustness requirements, wide area network (WAN) connections, such as cellular and satellite network are needed, on top of wireless sensor networks. Different WAN connections have different characteristics in terms of availability, performance, and cost. We have proposed a novel scheme, called optimal placement for QoS and robustness (OPQR), which uses the canonical genetic algorithm to determine the numbers, locations, and types of WAN connections to be deployed to minimize cost while satisfying the QoS and robustness requirements. Evaluation results confirm that OPQR can indeed fulfil the desired requirements at minimum cost, and it is a very useful tool in cost-efficient communication network planning for transmission line monitoring. Specifically, OPQR can maintain cost below USD50 per day for a transmission line that has 80 towers spanning across 32 km, while maintaining the packet delay below 100 ms, packet delivery ratio above 99.99%, and each flow has two node-disjoint paths to the control center.

Towards more stable operation of the Tokyo Tier2 center

The Tokyo Tier2 center, which is located at the International Center for Elementary Particle Physics (ICEPP) in the University of Tokyo, was established as a regional analysis center in Japan for the ATLAS experiment. The official operation with WLCG was started in 2007 after the several years development since 2002. In December 2012, we have replaced almost all hardware as the third system upgrade to deal with analysis for further growing data of the ATLAS experiment. The number of CPU cores are increased by factor of two (9984 cores in total), and the performance of individual CPU core is improved by 20% according to the HEPSPEC06 benchmark test at 32bit compile mode. The score is estimated as 18.03 (SL6) per core by using Intel Xeon E5-2680 2.70 GHz. Since all worker nodes are made by 16 CPU cores configuration, we deployed 624 blade servers in total. They are connected to 6.7 PB of disk storage system with non-blocking 10 Gbps internal network backbone by using two center network switches (NetIron MLXe-32). The disk storage is made by 102 of RAID6 disk arrays (Infortrend DS S24F-G2840-4C16DO0) and served by equivalent number of 1U file servers with 8G-FC connection to maximize the file transfer throughput per storage capacity. As of February 2013, 2560 CPU cores and 2.00 PB of disk storage have already been deployed for WLCG. Currently, the remaining non-grid resources for both CPUs and disk storage are used as dedicated resources for the data analysis by the ATLAS Japan collaborators. Since all hardware in the non-grid resources are made by same architecture with Tier2 resource, they will be able to be migrated as the Tier2 extra resource on demand of the ATLAS experiment in the future. In addition to the upgrade of computing resources, we expect the improvement of connectivity on the wide area network. Thanks to the Japanese NREN (NII), another 10 Gbps trans-Pacific line from Japan to Washington will be available additionally with existing two 10 Gbps lines (Tokyo to New York and Tokyo to Los Angeles). The new line will be connected to LHCONE for the more improvement of the connectivity. In this circumstance, we are working for the further stable operation. For instance, we have newly introduced GPFS (IBM) for the non-grid disk storage, while Disk Pool Manager (DPM) are continued to be used as Tier2 disk storage from the previous system. Since the number of files stored in a DPM pool will be increased with increasing the total amount of data, the development of stable database configuration is one of the crucial issues as well as scalability. We have started some studies on the performance of asynchronous database replication so that we can take daily full backup. In this report, we would like to introduce several improvements in terms of the performances and stability of our new system and possibility of the further improvement of local I/O performance in the multi-core worker node. We also present the status of the wide area network connectivity from Japan to US and/or EU with LHCONE.

Optimal configuration of fault-tolerance parameters for distributed replicated server access

Server replication is a common fault-tolerance strategy to improve transaction dependability for services in communications networks. In distributed architectures, fault-diagnosis and recovery are implemented via the interaction of the server replicas with the clients and other entities such as enhanced name servers. Such architectures provide an increased number of redundancy configuration choices. The influence of a (wide area) network connection can be quite significant and induce trade-offs between dependability and user-perceived performance. This paper develops a quantitative stochastic model using stochastic activity networks (SAN) for the evaluation of performance and dependability metrics of a generic transaction-based service implemented on a distributed replication architecture. The composite SAN model can be easily adapted to a wide range of client-server applications deployed in replicated server architectures. In order to obtain insight into the system behaviour, a set of relevant environment parameters and controllable fault-tolerance parameters are chosen and the dependability/performance trade-off is evaluated.

DCaaS: Data Consistency as a Service for Managing Data Uncertainty on the Clouds

Ensuring data correctness over partitioned distributed database systems is a classical problem. Classical solutions proposed to solve this problem are mainly adopting locking or blocking techniques. These techniques are not suitable for cloud environments as they produce terrible response times; due to the long latency and faultiness of wide area network connections among cloud datacenters. One way to improve performance is to restrict access of users-bases to specific datacenters and avoid data sharing between datacenters. However, conflicts might appear when data is replicated between datacenters; nevertheless change propagation timeliness is not guaranteed. Such problems created data uncertainty on cloud environments. Managing data uncertainty is one of the main obstacles for supporting global distributed transactions on the clouds. To overcome this problem, this paper proposes an quota-based approach for managing data uncertainty on the clouds that guarantees global data correctness without global locking or blocking. To decouple service developers from the hassles of managing data uncertainty, we propose to use a new platform service (i.e. Data Consistency as a Service (DCaaS)) to encapsulate the proposed approach. DCaaS service also ensures SaaS services cloud portability, as it works as a cloud adapter between SaaS service instances. Experiments show that proposed approach realized by the DCaaS service provides much better response time when compared with classical locking and blocking techniques.

An empirical analysis of serendipitous media sharing among campus-wide wireless users

Contemporary systems use centralized as well as peer-to-peer mechanisms for the large scale distribution of media objects. In this work, we investigate a serendipitous mechanism for directly sharing media objects among a local community of wireless users. This localized sharing is attractive when wide area network connectivity is undesirable, expensive or unavailable; especially when the shared media objects are large. With some restrictions, such localized sharing of media objects is also acceptable to content owners. However, localized sharing has to contend with far fewer media providers who may also not offer the variety of objects available from wide-area services. We collected empirical data from the widely deployed Apple iTunes application for our analysis. We showed that users are already making a significant amount of media objects available for serendipitous sharing. Our analysis showed that the shared object annotations exhibited a Zipfian long tail distribution. The availability patterns of wireless iTunes users and the object annotations makes serendipitous sharing inappropriate for scenarios that require access to a specific object. Instead, mechanisms that allow the user to specify classes of interesting objects are better suited for such users. Also, given the smaller scale of these systems, serendipitous sharing can benefit from approaches that allow users to disseminate a compact representation of their shared objects. Though the wireless user availability rates was not as high as what was observed in a corporate desktop setting, a large fraction of the users showed high temporal consistency. This allows for high availability with reasonable replication during weekday daytime hours. We answer important questions regarding the viability of a campus-wide media sharing system.

Telemetry Via Wi-Fi: A Case Study

Telemetry Via Wi-Fi: A Case Study

Self-Adaptive Configuration of Visualization Pipeline Over Wide-Area Networks

Next-generation scientific applications require the capability to visualize large archival data sets or on-going computer simulations of physical and other phenomena over wide-area network connections. To minimize the latency in interactive visualizations across wide-area networks, we propose an approach that adaptively decomposes and maps the visualization pipeline onto a set of strategically selected network nodes. This scheme is realized by grouping the modules that implement visualization and networking subtasks and mapping them onto computing nodes with possibly disparate computing capabilities and network connections. Using estimates for communication and processing times of subtasks, we present a polynomial-time algorithm to compute a decomposition and mapping to achieve minimum end-to-end delay of the visualization pipeline. We present experimental results using geographically distributed deployments to demonstrate the effectiveness of this method in visualizing data sets from three application domains.

CORBA-based solution for remote participation in SST-1 tokamak control and operation

The steady state superconducting tokamak (SST-1) central control system is a distributed heterogeneous process communication system built on socket programming. It consists of machine, experiment and discharge control plus timing and a database. The software controls and monitors SST-1 subsystems: water-cooling, power supplies, cryogenics and vacuum over a local area network (LAN). The SST-1 control room is the place where all the activities like session announcement, machine control, experiment control, discharge control and monitoring are performed. We have realized that, instead of having a single monitoring place, we should have multiple monitoring points and it should be made possible to control the experiment from any PC over the LAN. In order to meet such requirements for remote participation in tokamak operation, we are upgrading the existing software. The upgraded software is based on Common Object Request Broker Architecture (CORBA) technology. The software is utilizing CORBA-services such as event service, naming services, interface repository and security services. The inherent features of CORBA make the software, platform and language independent. The software supports a variety of communication paradigms including publish–subscribe, peer-to-peer, and request–reply. Based on this software, one can participate in SST-1 tokamak operation from the LAN, or a wide area network (WAN) connection anywhere on the Internet. Each user can customize plasma parameters and diagnostics data that he wants to monitor, at any time without any change in the software and a copy of these parameters will be available to him. This paper focuses on the publish–subscribe communication paradigm and its application for a machine monitoring system.