Cooperative distributed antenna systems have drawn considerable attention in recent years due to their potential enhance both the coverage and spectral efficiency of mobile communication systems. In this article conceptual description a cooperative DAS for communications is presented together with key techniques DASs, including multiple- input multiple-output single multiple users, handover, transmit power allocation. Furthermore, theoretical simulation results on or DASs are given compared...

软件定义网络(software-defined networking,简称SDN)技术分离了网络的控制平面和数据平面,为研发网络新应用和未来互联网技术提供了一种新的解决方案.综述了基于OpenFlow 的SDN 技术发展现状,首先总结了逻辑控制和数据转发分离架构的研究背景,并介绍了其关键组件和研究进展,包括OpenFlow交换机、控制器和SDN技术,然后从4 个方面分析了基于OpenFlow 技术目前所面临的问题和解决思路.结合近年来的发展现状,归纳了在校园网、数据中心以及面向网络管理和网络安全方面的应用,最后探讨了未来的研究趋势.;The control and data planes are decoupled in software-defined networking, which provide a new solution for research on network applications future Internet technologies. The development status of OpenFlow-based SDN...

With the deep integration of information and communication technology, network performance existing switched Ethernet cannot meet growing control management demands industrial production. To solve time-delay sub-network transmission balance problem, a multiobjective nondominated sorting genetic algorithm based on mapping matrix is proposed, in which new topology model established to reflect flexible format. Meanwhile, an adjacency introduced as code embody actual structure several special...

Abstract Graph neural networks (GNNs) have emerged as a forefront in deep learning, notably influencing research mechanical fault diagnosis. Transfer particularly through domain adaptation (DA) techniques, has found application machinery diagnosis by training models under one working condition and deploying them another. While efforts been made to integrate GNNs with DA techniques alleviate data distribution discrepancies investigating the inter-sample relationships, challenges persist:...

The impact and influence that a religious tradition can have amongst culturally out-group populations be quite unexpected even “boomerang” back home in equally unpredictable ways. This article explores one example of Chinese religion’s cultural within the Western psychiatric community using Daoism its appropriation by analytical psychologist Carl Jung. Although elements Daoism, such as Daoist Internal Alchemy or Yijing, integrated into system practices, was not straightforward. It will...

The Distributed Denial of Service (DDoS) attack has seriously harmed network availability over decades and there is still no effective defense mechanism. emerging software-defined networking (SDN) gives a new way to rethink the DDoS attacks. In this paper, we first modeled attacks from perspective architecture. Then security mechanism (SDSNM) was proposed remove or restrict these necessary conditions which were summarized model. SDSNM mainly implemented at edge SDN networks as well inherits...

The control and data planes are decoupled in software-defined networking (SDN), which enables both to evolve independently, brings about many advantages such as high flexibility, programmability, rapid implementation of new network protocols. However, order improve the scalability plane at present, some functionalities added plane, is probably impact on generality plane. key challenge adding strike a careful balance between We propose basic principles that should comply with, based...

Wireless sensor network is a kind of self-organization wireless which taking the data as center. The node in intensive, huge quantity and covering large area. Aiming at characters wide range area, amount information, complexity real-time transmission rural district, this paper developed system based on ZigBee technology for greenhouse consists nodes, cluster, clustering nodes task management nodes. Since energy efficiency one most decisive factors designing node, new protocol managing slots...

Monarch is a globally-distributed in-memory time series database system in Google. runs as multi-tenant service and used mostly to monitor the availability, correctness, performance, load, other aspects of billion-user-scale applications systems at Every second, ingests terabytes data into memory serves millions queries. has regionalized architecture for reliability scalability, global query configuration planes that integrate regions unified system. On top its distributed architecture,...

There are trade-offs among performance, energy, and device endurance for storage systems. Designs optimized one dimension or workload often suffer in another. Therefore, it is important to study the enable adaptation workloads dimensions. As Flash SSD has emerged, hybrid drives have been studied more closely. However, hybrids mainly designed high throughput, efficient energy consumption, improving endurance—leaving quantitative on unexplored. Past studies also lack a concrete model help...

Detecting large flows in a software-defined network accurately is important for many applications. However, due to the constraints of measurement resources such as TCAMs, existing solutions often suffer from feasibility and accuracy issues. In this letter, by combining advantages sampling flow counting, we propose FlowMon, sample fetch-based two-stage detection mechanism. FlowMon first captures suspicious through coarse-grained method, then notifies SDN controller determine true these ones...

The Information-Centric Networking (ICN) paradigm is proved to have the advantages of decreasing data delivery latency, enhancing user mobility, etc. However, current implementations ICN require changing infrastructure Internet, which hinders its deployment and development. Meanwhile, Software Defined (SDN) emerges as a viable solution facilitate new network without disrupting production traffic by decoupling control plane from forwarding plane. In this paper, essential properties reflect...

A medical system based on wireless sensor network technology is established. Firstly, the structure of a two-tiered embedded Web Server for collecting and analyzing examination data presented. Then designs software hardware systems physiological node base station (sink node) are The communication between nodes, sink nodes remote central server connected in one following ways, including Internet, GSM(Global System Mobile Communications) short message, telephone modem. idea this work to make...

Network function virtualization (NFV) is a promising network paradigm that enables the design and implementation of novel services with lower cost, increased agility, faster time-to-value. However, anomalies caused by software malfunction, hardware failure, mis-configuration, or cyber attacks can greatly degrade performance NFV networks. A few matrix decomposition-based methods have shown their effectiveness in finding existence network-wide anomalies. little attention has been paid to...

The availability is an important issue of software-defined networking (SDN). In this paper, the experiments based on a SDN testbed showed that resource utilization data plane and control changed drastically when DDoS attacks happened. This mainly because send large number fake flows to network in short time. Based observation analysis, defense mechanism legitimate source destination IP address database proposed paper. Firstly, each flow abstracted as source-destination pair (LSDIAD)...

This paper presents a vegetated flow and sediment transport model for investigating flow–vegetation–sediment interactions. Vegetation-induced turbulence is simulated by k−ε closure, in which shear stem-scale wake turbulent kinetic energies are solved separately. The simulates both unidirectional oscillatory flows as well structures reasonably with the skill greater than 0.8 coefficient of determination 0.95, better agreements between simulations measurements observed cases large stem...