基于云计算的教学管理信息系统研究

教学管理信息系统是教育信息化的重要组成部分。教育信息化向云端发展,在移动中应用是未来发展的趋势。云计算为教学管理信息系统提供了一个全新的平台,文章在教学管理信息系统功能分析的基础上,结合云计算技术特点,提出一种基于云计算的教学管理信息系统的架构,并讨论其实现方案。     

Multi-tenant Verification-as-a-Service (VaaS) in a cloud

Formal methods and verification technique are often used to develop mission-critical systems. Cloud computing offers new computation models for applications and the new model can be used for formal verification. But formal verification tools and techniques may need to be updated to exploit the cloud architectures. Multi-Tenant Architecture (MTA) is a design architecture used in SaaS (Software-as-a-Service) where a tenant can customize its applications by integrating either services already stored in the SaaS database or newly supplied services. This paper proposes a new concept VaaS (Verification-as-a-Service), similar to SaaS, by leveraging the computing power offered by a cloud environment with automated provisioning, scalability, and service composition. A VaaS hosts verification software in a cloud environment, and these services can be called on demand, and can be composed to verify a software model. This paper presents a VaaS architecture with components, and ways that a VaaS can be used to verify models. Bigragh is selected as the modeling language for illustration as it can model mobile applications. A Bigraph models can be verified by first converting it to a state model, and the state model can be verified by model-checking tools. The VaaS services combination model and execution model are also presented. The algorithm of distributing VaaS services to a cloud is given and its efficiency is evaluated. A case study is used to demonstrate the feasibility of a VaaS.     

Efficient application scheduling in mobile cloud computing based on MAX–MIN ant system

Combining the advantages of mobile computing and cloud computing, Mobile Cloud Computing (MCC) greatly enriches the types of applications on mobile devices and enhances the quality of service of the applications. Under various circumstances, researchers have put forward several MCC architectures. However, it still remains a challenging task of how to design a reasonable mobile cloud model with efficient application processing structure for some particular environment. This paper firstly presents a Hybrid Local Mobile Cloud Model (HLMCM) with detailed application scheduling structure. Secondly, a scheduling algorithm for HLMCM based on MAX–MIN Ant System is put forward. Finally, the effectiveness and suitability of our proposed algorithms are evaluated through a series of simulation experiments.     

IC cloud: Enabling compositional cloud

Cloud computing has attracted great interest from both academic and industrial communities. Different paradigms, architectures and applications based on the concept of cloud have emerged. Although many of them have been quite successful, efforts are mainly focusing on the study and implementation of particular setups. However, a generic and more flexible solution for cloud construction is missing. In this paper, we present a composition-based approach for cloud computing (compositional cloud) using Imperial College Cloud (IC Cloud) as a demonstration example. Instead of studying a specific cloud computing system, our approach aims to enable a generic framework where various cloud computing architectures and implementation strategies can be systematically studied. With our approach, cloud computing providers/adopters are able to design and compose their own systems in a quick and flexible manner. Cloud computing systems will no longer be in fixed shapes but will be dynamic and adjustable according to the requirements of different application domains.     

云环境中Web应用的微服务架构评估

云计算为我们提供了一种全新、高效的方式来部署可扩展的Web应用,这种方式使企业的应用可以按需对计算资源进行分配.微服务架构用于将庞大复杂的应用系统拆分为一系列可独立开发、测试、部署、运行、升级的服务模块.微服务架构为大批互联网企业实现云环境中的应用扩展、降低应用开发复杂度、实现敏捷开发提供了更加有效地方法.本文分析并测试了微服务架构模式,通过一个具体案例——在云环境中开发和部署的企业级应用系统,对两种架构模式实现（单体架构模式和微服务架构模式）进行性能测试,得出评估结果,这些结果对解决企业级应用微服务化中可能遇到的问题具有一定指导意义.     

CGMP: cloud-assisted green multimedia processing

With continued advancements of mobile computing and communications, emerging novel multimedia services and applications have attracted lots of attention and been developed for mobile users, such as mobile social network, mobile cloud medical treatment, mobile cloud game. However, because of limited resources on mobile terminals, it is of great challenge to improve the energy efficiency of multimedia services. In this paper, we propose a cloud-assisted green multimedia processing architecture (CGMP) based on mobile cloud computing. Specifically, the tasks of multimedia processing with energy-extensive consumption can be offloaded to the cloud, and the face recognition algorithm with improved principal component analysis and nearest neighbor classifier is realized on CGMP based cloud platform. Experimental results show that the proposed scheme can effectively save the energy consumption of the equipment.     

Building mobile multimedia services: a hybrid cloud computing approach

Mobile multimedia services are in high demand, but their development comes at high costs. The emergent computing paradigm cloud computing has great potential to embrace these issues. In fact, we are at the early stage of the coalescence of cloud computing, mobile multimedia and the Web. Motivated by the tremendous success story of the Web based on its simplicity principles, we argue for a comprehensive review on current practices of web and mobile multimedia cloud computing techniques for avoiding frictions. We draw on experience from the development of advanced collaborative multimedia web applications utilizing multimedia metadata standards like MPEG-7 and real-time communication protocols like XMPP. We propose our i5CLoud, a hybrid cloud architecture, which serves as a substrate for scalable and fast time-to-market mobile multimedia services. This paper demonstrates the applicability of emerging cloud computing concepts for mobile multimedia.     

基于TrustZone的可信移动终端云服务安全接入方案

可信云架构为云计算用户提供了安全可信的云服务执行环境,保护了用户私有数据的计算与存储安全. 然而在移动云计算高速发展的今天, 仍然没有移动终端接入可信云服务的安全解决方案. 针对上述问题, 提出了一种可信移动终端云服务安全接入方案, 方案充分考虑了移动云计算应用背景, 利用ARM TrustZone硬件隔离技术构建可信移动终端, 保护云服务客户端及安全敏感操作在移动终端的安全执行, 结合物理不可克隆函数技术, 给出了移动终端密钥与敏感数据管理机制. 在此基础之上, 借鉴可信计算技术思想, 设计了云服务安全接入协议, 协议兼容可信云架构, 提供云服务端与移动客户端间的端到端认证. 分析了方案具备的6种安全属性, 给出了基于方案的移动云存储应用实例, 实现了方案的原型系统. 实验结果表明, 可信移动终端TCB较小, 方案具有良好的可扩展性和安全可控性, 整体运行效率较高.     

云计算在电子政务系统中的应用研究

云计算是指IP技术架构下的网络计算,云计算技术将不仅提供传统意义的IT资源和应用服务,而且将支持包括IT、通信、电视、移动和物联等一切互联网技术融合后的资源使用和业务应用。本文着重介绍云计算数据库的基本思想和实现过程中需要解决的基本问题,论述利用云计算构建电子政务系统的模型和实现方案。云计算以其安全可靠的数据存储和强大的计算能力,必将对电子政务系统的信息化建设产生积极的影响。     

Technologies for Web and cloud service interaction: a survey

The evolution of Web and service technologies has led to a wide landscape of standards and protocols for interaction between loosely coupled software components. Examples range from Web applications, mashups, apps, and mobile devices to enterprise-grade services. Cloud computing is the industrialization of service provision and delivery, where Web and enterprise services are converging on a technological level. The article discusses this technological landscape and, in particular, current trends with respect to cloud computing. The survey focuses on the communication aspect of interaction by reviewing languages, protocols, and architectures that drive today’s standards and software implementations applicable in clouds. Technological advances will affect both client side and service side. There is a trend toward multiplexing, multihoming, and encryption in upcoming transport mechanisms, especially for architectures, where a client simultaneously sends a large number of requests to some service. Furthermore, there are emerging client-to-client communication capabilities in Web clients that could establish a foundation for upcoming Web-based messaging architectures.     

云计算体系结构及应用实例分析

云计算包含两个方面的基本内容：一、描述用于构造应用程序的基础架构;二、描述建立在这种基础架构之上的应用和扩展服务;针对云计算的体系结构及应用实例,剖析其背后的技术含义以及当前云计算平台所采用的实现方法,进而评析当前云计算的发展状况,探讨实现云计算的技术方案。     

A fault‐tolerant dynamic scheduling method on hierarchical mobile edge cloud computing

Mobile edge cloud computing has been a promising computing paradigm, where mobile users could offload their application workloads to low‐latency local edge cloud resources. However, compared with remote public cloud resources, conventional local edge cloud resources are limited in computation capacity, especially when serve large number of mobile applications. To deal with this problem, we present a hierarchical edge cloud architecture to integrate the local edge clouds and public clouds so as to improve the performance and scalability of scheduling problem for mobile applications. Besides, to achieve a trade‐off between the cost and system delay, a fault‐tolerant dynamic resource scheduling method is proposed to address the scheduling problem in mobile edge cloud computing. The optimization problem could be formulated to minimize the application cost with the user‐defined deadline satisfied. Specifically, firstly, a game‐theoretic scheduling mechanism is adopted for resource provisioning and scheduling for multiprovider mobile applications. Then, a mobility‐aware dynamic scheduling strategy is presented to update the scheduling with the consideration of mobility of mobile users. Moreover, a failure recovery mechanism is proposed to deal with the uncertainties during the execution of mobile applications. Finally, experiments are designed and conducted to validate the effectiveness of our proposal. The experimental results show that our method could achieve a trade‐off between the cost and system delay.     

基于ILS-PSO算法的移动云计算DAG图的任务调度研究与应用

移动云计算已经深入到人们工作和生活的各个方面,同时也对移动设备的续航时间、计算能力,存储容量和安全性提出了更高的要求。移动云计算网络中的移动设备由于资源有限、通信受限,无法满足复杂应用的要求。为了解决移动云计算环境下复杂应用的有效使用问题,对移动设备网络和DAG任务图进行深入研究,将复杂应用分解成多个不相交的集合分配给移动设备并行执行,满足移动设备电池容量的约束下,提出了粒子群优化(PSO)算法求解最优调度方案的方法,并且应用迭代局部搜索(ILS)策略,保证了全局和局部搜索的平衡。     

移动边缘网络中计算迁移与内容缓存研究综述

随着移动设备数量的爆炸性增长以及许多新兴应用的出现,移动网络的流量呈指数级增长.传统的集中式网络架构由于回程链路负载过重、时延较长,无法满足移动用户的需求.因此,提出了将网络能力从核心网开放至边缘网的新体系结构,即移动边缘计算（MEC）.移动边缘计算能够在移动蜂窝网络的边缘提供轻量级的云计算和存储能力.对移动边缘计算相关的最新研究成果进行了详尽的回顾：首先,概述了移动边缘计算的发展历程、关键问题和支撑技术;然后,针对MEC架构、计算迁移、边缘缓存和服务编排这4个关键研究问题进行了全面的综述,并讨论了增强现实、虚拟现实、动态内容交付、车联网和物联网等移动边缘计算中的典型应用案例;最后,从移动边缘计算功能增强、服务质量保障和安全可用性这3个方面展望了移动边缘计算的开放式研究挑战和未来的发展趋势.     

SAaaS: a cloud computing service model using semantic‐based agent

Cloud computing, a common business model, provides cloud resources on demand to consumers over the Internet. However, because cloud computing lacks a uniform method of representing knowledge, which can offer customers a comprehensive solution for managing and developing cloud applications, cloud computing has low reuse potential. This work proposes a Semantic Agent as a Service (SAaaS), which was developed using Unified Modeling Language modelling. The SAaaS architecture is based on research into Cloud Computing, Semantic Web and Multi‐Agent Systems. The architecture can be combined with existing cloud service models, such as Software as a Service, Platform as a Service and Infrastructure as a Service, to design intelligent cloud computing applications. To demonstrate the efficacy of SAaaS, a Semantic‐based Project Resources Sharing Platform, an intelligent cloud computing application based on the SAaaS framework, is implemented to provide project resources on demand, consistent with the needs of project members.     

Media Cloud: When Media Revolution Meets Rise of Cloud Computing

Media content has become the major traffic of Internet and will keep on increasing rapidly. Various innovative media applications, services, devices have emerged and people tend to consume more media contents. We are meeting a media revolution. But to maintain the sustainability of the tremendous media consumption, it requires great capability of media processing, which demands huge amount of computing resources. Meanwhile cloud computing has emerged as a prosperous technology and the cloud computing platform has become a fundamental facility providing various services, great computing power, massive storage and bandwidth with modest cost. The integration of cloud computing and media processing is therefore a natural choice for both of them, and hence comes forth the media cloud. In this paper we make a comprehensive overview on the recent media cloud research work. We first discuss the challenges of the media cloud, and then summarize its architecture, the processing, and its storage, delivery and resource management mechanisms. As the result, we propose a new architecture for the media cloud. At the end of this paper, we make suggestions on building media clouds and propose several future research topics as the conclusion.     

Architecting cloud‐enabled systems: a systematic survey of challenges and solutions

The literature on the challenges of and potential solutions to architecting cloud‐based systems is rapidly growing but is scattered. It is important to systematically analyze and synthesize the existing research on architecting cloud‐based software systems in order to build a cohesive body of knowledge of the reported challenges and solutions. We have systematically identified and reviewed 133 papers that report architecture‐related challenges and solutions for cloud‐based software systems. This paper reports the methodological details, findings, and implications of a systematic review that has enabled us to identify 44 unique categories of challenges and associated solutions for architecting cloud‐based software systems. We assert that the identified challenges and solutions classified into the categories form a body of knowledge that can be leveraged for designing or evaluating software architectures for cloud‐based systems. Our key conclusions are that a large number of primary studies focus on middleware services aimed at achieving scalability, performance, response time, and efficient resource optimization. Architecting cloud‐based systems presents unique challenges as the systems to be designed range from pervasive embedded systems and enterprise applications to smart devices with Internet of Things. We also conclude that there is a huge potential of research on architecting cloud‐based systems in areas related to green computing, energy efficient systems, mobile cloud computing, and Internet of Things. Copyright © 2016 John Wiley & Sons, Ltd.     

基于组件的嵌入式移动数据库系统架构

移动计算环境下网络连接和配置的动态变化,使得嵌入式移动数据库需要有效处理各种不同性质的事务。这种数据库应该具有通用性,可以高效地使用资源,快捷地裁减和移植于各种嵌入式系统中,适用于多种移动嵌入式应用。简要介绍了目前已出现的商业嵌入式移动数据库的体系结构,分析了其在功能配置和适应移动计算环境动态需求方面的不足。运用组件思想设计一种完整的可配置嵌入式移动数据库系统架构,解决由移动计算环境所引入的一些结构性问题。     

Quantitative survivability evaluation of three virtual machine-based server architectures

Virtual machine-based services have become very popular in data centers and cloud computing in recent years. Efficient redundancy technology of virtual machine provides good availability for services; thus, it has become possible to provide continuous services even if the system suffers intrusions. So far, many intrusion tolerant server architectures have been developed based on virtual machine technology in academia and industry. Unfortunately, to the best of our knowledge, there is very little work done on evaluating the survivability of virtual machine-based server architectures in the literature.In this paper, we focus on analyzing and evaluating the survivability of three virtual machine-based architectures, which are load balance server architecture (LBSA), isolated component server architecture (ICSA), and Byzantine fault tolerant server architecture (BFTSA). As a reference, a traditional server cluster without virtual machines is also analyzed and compared. We model different architectures with Continuous Time Markov Chain (CTMC). We analyze the transient behaviors and steady states of different virtual machine-based architectures. Furthermore, the costs of the traditional server cluster and the virtual machine-based architectures are compared in terms of processing costs, memory costs, communication costs, and fail-safe fault tolerance. The results show that BFTSA has better survivability than LBSA and ICSA, but with longer time to reach the steady states and higher communication costs.     

Matrix based proactive resource provisioning in mobile cloud environment

Mobile cloud computing is a dynamic, virtually scalable and network based computing environment where mobile device acts as a thin client and applications run on remote cloud servers. Mobile cloud computing resources required by different users depend on their respective personalized applications. Therefore, efficient resource provisioning in mobile clouds is an important aspect that needs special attention in order to make the mobile cloud computing a highly optimized entity. This paper proposes an adaptive model for efficient resource provisioning in mobile clouds by predicting and storing resource usages in a two dimensional matrix termed as resource provisioning matrix. These resource provisioning matrices are further used by an independent authority to predict future required resources using artificial neural network. Independent authority also checks and verifies resource usage bill computed by cloud service provider using resource provisioning matrices. It provides cost computation reliability for mobile customers in mobile cloud environment. Proposed model is implemented on Hadoop using three different applications. Results indicate that proposed model provides better mobile cloud resources utilization as well as maintains quality of service for mobile customer. Proposed model increases battery life of mobile device and decreases data usage cost for mobile customer.