检索结果-南通市图书馆

Energy-efficient Virtual Machine Allocation Technique Using Flower Pollination Algorithm in Cloud datacenter:A Panacea to Green Computing

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2019年第2期16卷 354-366页

作者： Mohammed Joda Usman Abdul Samad Ismail Hassan Chizari Gaddafi Abdul-Salaam Ali Muhammad Usman Abdulsalam Yau Gital Omprakash Kaiwartya Ahmed Aliyu Department of Maths Bauchi State University GadauBauchi 81007Nigeria Department of Computer Science Universiti Teknology MalaysiaSkudai Johor 81310Malaysia School of Computing and Technology Park CampusUniversity of Gloucestershire Cheltenham GL50 4SHUK Department of Computer Science Kwame Nkrumah University of Science and TechnologyKumasi 00233Ghana Department of Maths and Computer Federal College of Education Technical GombeGombe 072158Nigeria Department of Maths Abubakar Tafawa Balewa University BauchiBauchi 81027Nigeria Department of Computer and Information Technology Northumbria UniversityNewcastle NE1SSTUK

Cloud computing has attracted significant interest due to the increasing service demands from organizations offloading computationally intensive tasks to ***,datacenter infrastructure comprises hardware resources that consume high amount of energy and give out carbon emissions at hazardous *** cloud datacenter,Virtual Machines(VMs)need to be allocated on various Physical Machines(PMs)in order to minimize resource wastage and increase energy *** allocation problem is *** finding an exact solution is complicated especially for large-scale *** this con text,this paper proposes an Energy-oriented Flower Pollination Algorithm(E-FPA)for VM allocation in cloud datacenter environments.A system framework for the scheme was developed to enable energy-oriented allocation of various VMs on a *** allocation uses a strategy called Dynamic Switching Probability(DSP).The framework finds a near optimal solution quickly and balances the exploration of the global search and exploitation of the local *** considers a processor,storage,and memory constraints of a PM while prioritizing energy-oriented allocation for a set of *** performed on MultiRecCloudSim utilizing planet workload show that the E-FPA outperforms the Genetic Algorithm for Power-Aware(GAPA)by 21.8%,Order of Exchange Migration(OEM)ant colony system by 21.5%,and First Fit Decreasing(FFD)by 24.9%.Therefore,E-FPA significantly improves datacenter performance and thus,enhances environmental sustainability.

关键词： virtualization green computing cloud datacenter energy optimization

On Meeting Deadlines in datacenter Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2013年第3期18卷 273-285页

作者： Li Chen Baochun Li Bo Li the Department of Electrical and Computer Engineering University of Toronto the Department of Computer Science Hong Kong University of Science and Technology

datacenters have become increasingly important to host a diverse range of cloud applications with mixed workloads. Traditional applications hosted by datacenters are throughput-oriented without delay requirements, but newer generations of cloud applications, such as web search, recommendations, and social networking, typically employ a tree-based Partition-Aggregate structure, which may incur bursts of traffic. As a result, flows in these applications have stringent latency requirements, i.e., flow deadlines need to be met in order to achieve a satisfactory user experience. To meet these flow deadlines, research efforts in the recent literature have attempted to redesign flow and congestion control protocols that are specific to datacenter networks. In this paper, we focus on the new array of deadline-sensitive flow control protocols, thoroughly investigate their underlying design principles, analyze the evolution of their designs, and evaluate the tradeoffs involved in their design choices.

关键词： datacenter transport protocols design principles

Is Minimizing Flow Completion Time the Optimal Way in Meeting Flow's Deadline in datacenter Networks

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

China Communications 2016年第S1期13卷 6-15页

作者： XU Yakun LUO Hongbin REN Fei National Engineering Laboratory for Next Generation Internet Technologies School of Electronic and Information Engineering Beijing Jiaotong University

In modern datacenters, the most common method to solve the network latency problem is to minimize flow completion time during the transmission process. Following the soft real-time nature, the optimization of transport latency is relaxed to meet a flow's deadline in deadline-sensitive services. However, none of existing deadline-sensitive protocols consider deadline as a constraint condition of *** can only simplify the objective of meeting a flow's deadline as a deadline-aware mechanism by assigning a higher priority for tight-deadline constrained flows to finish the transmission as soon as possible, which results in an unsatisfactory effect in the condition of high fan-in degree. It drives us to take a step back and rethink whether minimizing flow completion time is the optimal way in meeting flow's deadline. In this paper, we focus on the design of a soft real-time transport protocol with deadline constraint in datacenters and present a flow-based deadline scheduling scheme for datacenter networks(FBDS).FBDS makes the unilateral deadline-aware flow transmission with priority transform into a compound centralized single-machine deadlinebased flow scheduling decision. In addition, FBDS blocks the flow sets and postpones some flows with extra time until their deadlines to make room for the new arriving flows in order to improve the deadline meeting rate. Our simulation resultson flow completion time and deadline meeting rate reveal the potential of FBDS in terms of a considerable deadline-sensitive transport protocol for deadline-sensitive interactive services.

关键词： datacenter networks deadline preemptive scheduling flow completion time

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

惠普全方位服务datacenter

互联网世界 2001年第11期 79-79页

作者：怡然

Harmonia: Explicit Congestion Notification and Credit-Reservation Transport Converged Congestion Control in datacenters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2021年第5期36卷 1071-1086页

作者： Ding-Huang Hu De-Zun Dong Yang Bai Shan Huang Ze-Jia Zhou Zi-Hao Wei Xiang-Ke Liao College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Bursty traffic and thousands of concurrent flows incur inevitable network congestion in datacenter networks(DCNs)and then affect the overall *** transport protocols are developed to mitigate the network congestion,including reactive and proactive *** schemes use different congestion signals,such as explicit congestion notification(ECN)and round trip time(RTT),to handle the network congestion after congestion ***,with the growth of scale and link speed in datacenters,reactive schemes encounter a significant problem of slow responding to *** the contrary,proactive protocols(e.g.,credit-reservation protocols)are designed to avoid congestion before it occurs,and they have the advantages of zero data loss,fast convergence and low buffer *** credit-reservation protocols have not been widely deployed in current DCNs(e.g.,Microsoft,Amazon),which mainly deploy ECN-based protocols,such as data center transport control protocol(DCTCP)and data center quantized congestion notification(DCQCN).And in an actual deployment scenario,it is hard to guarantee one protocol to be deployed in every server at one *** credit-reservation protocol is deployed to DCNs step by step,the network will be converted to multi-protocol state and will face the following fundamental challenges:1)unfairness,2)high buffer occupancy,and 3)heavy tail ***,we propose Harmonia,aiming for converging ECN-based and credit-reservation protocols to fairness with minimal *** the best of our knowledge,Harmonia is the first to address the trouble of harmonizing proactive and reactive congestion *** the common ECN-based protocols-DCTCP and DCQCN,Harmonia leverages forward ECN and RTT to deliver real-time congestion information and redefines feedback *** the evaluation,the results show that Harmonia effectively solves the unfair link allocation,eliminating the timeouts and addressing the buffer overflow.

关键词： datacenter credit-reservation protocol ECN-based(explicit congestion notification based)protocol multiprotocol converging

Enhancing Security by Using GIFT and ECC Encryption Method in Multi-Tenant datacenters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2023年第5期75卷 3849-3865页

作者： Jin Wang Ying Liu Shuying Rao R.Simon Sherratt Jinbin Hu School of Computer&Communication Engineering Changsha University of Science&TechnologyChangsha410004China School of Systems Engineering The University of ReadingRG66AYUK

Data security and user privacy have become crucial elements in multi-tenant data *** traffic types in the multi-tenant data center in the cloud environment have their characteristics and *** the data center network(DCN),short and long flows are sensitive to low latency and high throughput,*** traditional security processing approaches,however,neglect these characteristics and *** paper proposes a fine-grained security enhancement mechanism(SEM)to solve the problem of heterogeneous traffic and reduce the traffic completion time(FCT)of short flows while ensuring the security of multi-tenant traffic ***,for short flows in DCN,the lightweight GIFT encryption method is *** Intra-DCN long flows and Inter-DCN traffic,the asymmetric elliptic curve encryption algorithm(ECC)is *** NS-3 simulation results demonstrate that SEM dramatically reduces the FCT of short flows by 70%compared to several conventional encryption techniques,effectively enhancing the security and anti-attack of traffic transmission between DCNs in cloud computing ***,SEM performs better than other encryption methods under high load and in largescale cloud environments.

关键词： Multi-tenant datacenter user privacy transmission security GIFT ECC

Two-Phase Provisioning for HPC Tasks in Virtualized datacenters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Two-Phase Provisioning for HPC Tasks in Virtualized Datacent...

A Genetic Based Leader Election Algorithm for IoT Cloud Data Processing

International Conference on Emerging Trends in Computer and Electronics Engineering(ICETCEE’2012);International Conference on Advancements in Electrical and Power Engineering(ICAEPE’2012);International Conference on Trends in Industrial and Mechanical Engineering(ICTIME’2012);International Conference on Advances in Biological and Pharmaceutical Sciences (ICABPS’2012);International Conference on Chemical,Civil and Environment engineering(ICCEE’2012);International Conference on Management,Applied and Social Sciences(ICMASS’2012)

作者： Nawfal A. Mehdi Hussam Ali Ali Amer Ziyad.T.Abdul-Mehdi Univeristy Putra Malaysia department of computer science Baghdad University

This paper deals with running the lowest number of virtualized datacenter machines with the least completion time and efficient consumption of *** computing is based on the concept of offering computation services that are executed in datacenters. These datacenters require huge amount of power if they are at the peak load or the tasks are not distributed efficiently in their machines. Reducing power consumption has been an essential requirement for cloud resource providers not only to decrease operating costs, but also to improve the system *** paper addresses the issue of minimizing power consumption in datacenter servers and improving their load balancing simultaneously. An algorithm for task scheduling in virtualized datacenters is presented, that works in two phases;firstly lowering the number of running machines to decrease power consumption and secondly reducing the total datacenter load. An empirical study was done to simulate the proposed algorithm using a discrete events simulator. The results show an improvement in the datacenter load and power consumption.

关键词： datacenter Power consumption virtualization HPC.

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第8期68卷 2469-2486页

作者： Samira Kanwal Zeshan Iqbal Aun Irtaza Rashid Ali Kamran Siddique Department of Computer Science University of Engineering and TechnologyTaxila47050Pakistan School of Intelligent Mechatronics Engineering Sejong UniversitySeoulKorea School of Electrical and Computer Engineering Department of Information and Communication TechnologyXiamen University MalaysiaSepang43900Malaysia

In IoT networks,nodes communicate with each other for computational services,data processing,and resource *** of the time huge data is generated at the network edge due to extensive communication between IoT ***,this tidal data is transferred to the cloud data center(CDC)for efficient processing and effective data *** CDC,leader nodes are responsible for higher performance,reliability,deadlock handling,reduced latency,and to provide cost-effective computational services to the ***,the optimal leader selection is a computationally hard problem as several factors like memory,CPU MIPS,and bandwidth,etc.,are needed to be considered while selecting a leader amongst the set of available *** existing approaches for leader selection are monolithic,as they identify the leader nodes without taking the optimal approach for leader ***,for optimal leader node selection,a genetic algorithm(GA)based leader election(GLEA)approach is presented in this *** proposed GLEA uses the available resources to evaluate the candidate nodes during the leader election *** the first phase of the algorithm,the cost of individual nodes,and overall cluster cost is computed on the bases of available *** the second phase,the best computational nodes are selected as the leader nodes by applying the genetic operations against a cost function by considering the available *** GLEA procedure is then compared against the Bees Life Algorithm(BLA).The experimental results show that the proposed scheme outperforms BLA in terms of execution time,SLA Violation,and their utilization with state-of-the-art schemes.

关键词： IoT cloud computing datacenter leader election algorithm machine learning genetic algorithm

基于STEP协议的证券行情分析系统（LEVEL-2）的研究与实现

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于STEP协议的证券行情分析系统（LEVEL-2）的研究与实现

作者：刘成德贵州大学

学位级别：硕士

中国经济高速发展,中国证券市场越来越受到国家的重视,中国证券市场变得壮大和成熟,证券市场的技术也得到了很大的发展。然而我国证券市场行情的分析还存在着很大的问题。沪深证券交易所和券商和其他机构间都采用各自设计的非标准化的接... 详细信息

中国经济高速发展,中国证券市场越来越受到国家的重视,中国证券市场变得壮大和成熟,证券市场的技术也得到了很大的发展。然而我国证券市场行情的分析还存在着很大的问题。沪深证券交易所和券商和其他机构间都采用各自设计的非标准化的接口,数据信息交换模式不统一,编码方式不统一,接口定义不统一,业务数据流程不统一,存在对业务创新的适应性较差、适应成本高,不同市场间难于有效交换信息等问题。交易系统的改革也带动了行情分析系统的改革和提高,证券市场需要一个高质量、快速、大信息量的行情分析系统。这就需要引入国际化的信息交换协议。在国外,一些成熟的证券市场和银行系统已经有90%在使用FIX(Financial InformationExchange金融信息交换)协议,纽约交易所、泛欧交易所(EURONEXT)、墨西哥交易所、芝加哥期权交易所(CBOE)、新加坡交易所、澳大利亚交易所等均支持FIX协议。可以说FIX协议已经相当完善、成熟、安全的。中国证监会从1998年开始就计划和讨论证券行业的电子信息交换标准化,历经8年的研究,终于推出了适合我国证券市场的一种基于FIX4.4协议的STEP协议。STEP协议:(Securities Trading Exchange Protocol)证券交易数据交换协议,该协议是在国际上通用的金融信息交换协议FIX4.4的基础上结合我国证券市场的实际情况制定出来的标准协议,是国家金融“十五”科技攻关任务。于2004年2月,STEP通过了国家金融标准化委员会专家会议审核,正式成为国家标准,并定名为《证券交易数据交换协议》。证券行情分析系统的架构目前可以分为下面三种类型:A):基于Client/Service模式的架构C/S模式的优势是所占用的资源较少,速度快,传输质量较高。B):基于Brower/Service模式的架构B/S模式的优势是分布广,简单易用,可供大量的人同时使用。其劣势是对服务器端机器性能要求比较高。C):基于Mobile/Service模式的架构M/S模式的优势是容易普及,使用方便,但是其致命的劣势是成本太高、速度慢、信息量小。本文采用C/S架构模式,基于国家标准STEP协议,在通信过程中采用TCP/IP、UDP协议,详细地介绍了证券行情分析系统的整体架构、系统软件体系结构、系统内部进程间通信设计、服务器端的布局和架设、客户端设计和结构及服务器端和客户端通信、功能模块的划分等,成功实现了新一代行情分析系统(LEVEL-2),该系统已经在市场上成功的应用。本文所做的主要工作、技术难点与创新点如下:1.对国家标准JR╱T0022-2004 STEP(Securities Trading Exchange Protocol)协议进行了分析和研究。2.对上证所提供的STEP引擎进行了分析和研究,并且对Fix(Financial InformationExchange)协议的开放源代码进行研究,参考FIX协议的源代码开发出了适合自己的基于STEP协议的Level2DCD转码机,对上证所传来的行情进行解析、存盘、发布。3.对证券行情分析系统服务器端的架构进行了研究,服务器架设在不同的区域,如何协调认证服务器、均衡服务器和数据服务器,达到流量的最大化和通信的最优化是一个很重要的问题。4.参与了证券行情分析系统客户端的架构设计、功能模块的划分,并编写了部分代码、对代码进行了优化。使系统具有灵活性、可配置性、可扩展性,重用性,从系统设计的角度实现设计的模块化和可扩展的开放性。5.高效的进程池模式设计:针对系统的特点,即系统在生产过程中存在大量的数据访问请求,系统通过建立进程缓冲池,来减少创建及销毁时的资源消耗,提高系统效率。6.网络通讯接口API的封装:基于系统体系结构设计的考虑,为了实现软件体系结构的层次化,通讯层、应用层及业务层分开,系统对基于TCP/IP协议的socket底层通讯的网络接口进行了合理封装,封装后作为系统底层库函数提供给应用层程序调用,自己对Socket包的打包和拆包的处理。***下网络编程:设计基于TCP╱IP协议的通讯平台。由于系统设计过程中采用多服务模式,所以需要搭建一个专门用于各个服务之间交换信息的通讯平台,通讯方式选用异步通讯模式来实现。同时要考虑是使用长连接还是短连接。如果使用长连接,发送前需要考虑是否连接问题。根据系统不同业务的需求和性能指标的规定来确定具体采用那种连接方式。8.心跳包的设计:证券行情服务器端和客户端要保持长时间的通信,很难判断客户端由于某种故障和服务器端断开链接,因此采用了如QQ、MSN通用的通信检测方

关键词： STEP协议 STEP引擎证券行情行情分析系统 LEVEL-2 TCP/IP UDP Level2DCD datacenter 视图网络消息 K线图 Socket