一种SOA云服务平台架构研究与应用

在完美SOA分布式系统架构平台基础上,面向服务进行云架构模式的分析,建立以云端用户、云服务平台中心和云服务提供者构成的云架构模式,实现SOA云平台体系架构,将云服务提供者分成云服务接口层、云服务调度管理层、云计算服务层和云物理服务层。经过改进提高了云平台的服务能力和执行效率,并给出了提高该云平台调度效率的调度算法。通过数字校园云进行了云平台实例演示,显示了SOA云服务平台的架构和调度算法的快速服务响应能力。     

SOA与云计算的融合

云计算是一种新型的网络服务计算模式,作为对SOA的继承与发展,现如今已成为网络研究领域的热点. 本文在介绍了SOA和云计算特征的基础上,对SOA与云计算之间的可融合性进行了分析,并提出了一种基于SOA的云计算体系架构模型. 最后通过数字图书馆进行平台实例应用,显示了基于SOA的云计算体系架构的可行性.     

基于云的MIS开放式体系结构

为了解决企业的MIS向云计算转移过程中的问题,在对SOA与云计算的特征进行综述的基础上,分析了SOA与云计算之间的互补关系,提出采用SOA架构方法来构造基于云的MIS开放式体系结构,深入地阐述了相关概念,并且详述了服务请求者与服务提供者之间的交互过程,服务注册机制以及服务治理过程。最后,根据该体系结构模型,构造基于云的景区客流量预测系统,并对该系统的客流量预测服务的调用与修改进行详细说明,初步说明该体系结构的可行性和有用性。     

基于“云计算”的数字电视业务管理系统的研究

针对广电系统中数字电视媒体在业务的持续发展和广电系统运营维护管理方面的各种困境,综合了基于服务的SOA系统架构和"云计算"技术的商业运行模式,运用"云计算"的虚拟化、分布式、并行计算等技术,提出了基于"云计算"技术开发数字电视业务管理系统的方法,为今后广电行业实施的三网融合提供了一种新的设计思路。结合某市数字电视业务云架构的解决方案,说明"云计算"在广电系统构建数字电视业务管理系统中的应用。     

企业云服务体系结构设计框架

云计算应用和企业私有云建设不是简单的虚拟化和传统意义上的主机托管.为了着力提升企业信息资源的重用性、敏捷性和快速服务响应水平,以国防部体系结构框架DoDAF V2.0的服务视图模型为主体,提出一个基于面向服务体系结构（SOA）的企业云服务体系结构设计框架.通过服务视图模型间约束关系的研究和融合云计算模式的面向服务体系解析,建立相应的企业云服务体系结构设计规范和企业云计算应用实施环境.最后,提出了一个基于松耦合SOA的云应用解决方案,从而支持企业云服务体系结构设计和云计算应用技术实施.     

Mobile agent middleware for mobile computing

Mobile computing requires an advanced infrastructure that integrates suitable support protocols, mechanisms, and tools. This mobility middleware should dynamically reallocate and trace mobile users and terminals and permit communication and coordination of mobile entities. In addition, open and untrusted environments must overcome system heterogeneity and grant the appropriate security level. Solutions to these issues require compliance with standards to interoperate with different systems and legacy components and a reliable security infrastructure based on standard cryptographic mechanisms and tools. Many proposals suggest using mobile agent technology middleware to address these issues. A mobile agent moves entities in execution together with code and achieved state, making it possible to upgrade distributed computing environments without suspending service. We propose three mobile computing services: user virtual environment (UVE), mobile virtual terminal (MVT), and virtual resource management (VRM). UVE provides users with a uniform view of their working environments independent of current locations and specific terminals. MVT extends traditional terminal mobility by preserving the terminal execution state for restoration at new locations, including active processes and subscribed services. VRM permits mobile users and terminals to maintain access to resources and services by automatically requalifying the bindings and moving specific resources or services to permit load balancing and replication     

基于GAE云计算的区域移动医疗服务平台

针对医疗信息化与互联网应用现状, 提出面向区域移动医疗网络服务平台概念. 在分析移动医疗及其发展现状、云计算及其关键技术和Android平台应用开发模式的基础上, 首先提出基于云计算的移动医疗服务平台整体架构, 并分别从信息资源提供层、云计算平台层、医疗服务层和移动应用层等四个方面进行阐述; 然后在研究Google App Engine云服务平台的基础上, 对基于GAE的移动医疗服务平台的服务器端与客户端技术、数据模型等关键技术进行详细描述; 最后给出基于GAE的移动医疗服务平台的系统实现, 分别从平台服务器端和移动客户端两方面进行描述, 其中客户端实现基于Android移动操作系统, 为普通用户提供专家门诊信息、医药用品信息及其他功能.     

Analyzing, modeling and evaluating dynamic adaptive fault tolerance strategies in cloud computing environments

Failures are normal rather than exceptional in cloud computing environments, high fault tolerance issue is one of the major obstacles for opening up a new era of high serviceability cloud computing as fault tolerance plays a key role in ensuring cloud serviceability. Fault tolerant service is an essential part of Service Level Objectives (SLOs) in clouds. To achieve high level of cloud serviceability and to meet high level of cloud SLOs, a foolproof fault tolerance strategy is needed. In this paper, the definitions of fault, error, and failure in a cloud are given, and the principles for high fault tolerance objectives are systematically analyzed by referring to the fault tolerance theories suitable for large-scale distributed computing environments. Based on the principles and semantics of cloud fault tolerance, a dynamic adaptive fault tolerance strategy DAFT is put forward. It includes: (i) analyzing the mathematical relationship between different failure rates and two different fault tolerance strategies, which are checkpointing fault tolerance strategy and data replication fault tolerance strategy; (ii) building a dynamic adaptive checkpointing fault tolerance model and a dynamic adaptive replication fault tolerance model by combining the two fault tolerance models together to maximize the serviceability and meet the SLOs; and (iii) evaluating the dynamic adaptive fault tolerance strategy under various conditions in large-scale cloud data centers and consider different system centric parameters, such as fault tolerance degree, fault tolerance overhead, response time, etc. Theoretical as well as experimental results conclusively demonstrate that the dynamic adaptive fault tolerance strategy DAFT has high potential as it provides efficient fault tolerance enhancements, significant cloud serviceability improvement, and great SLOs satisfaction. It efficiently and effectively achieves a trade-off for fault tolerance objectives in cloud computing environments.     

Ontology-based access control model for security policy reasoning in cloud computing

There are many security issues in cloud computing service environments, including virtualization, distributed big-data processing, serviceability, traffic management, application security, access control, authentication, and cryptography, among others. In particular, data access using various resources requires an authentication and access control model for integrated management and control in cloud computing environments. Cloud computing services are differentiated according to security policies because of differences in the permitted access right between service providers and users. RBAC (Role-based access control) and C-RBAC (Context-aware RBAC) models do not suggest effective and practical solutions for managers and users based on dynamic access control methods, suggesting a need for a new model of dynamic access control that can address the limitations of cloud computing characteristics. This paper proposes Onto-ACM (ontology-based access control model), a semantic analysis model that can address the difference in the permitted access control between service providers and users. The proposed model is a model of intelligent context-aware access for proactively applying the access level of resource access based on ontology reasoning and semantic analysis method.     

基于云计算的信息系统数据采集分析系统的研究与设计

从云计算三个层次的服务模式出发,提出了一种基于云计算平台的分布式并行信息系统数据采集分析系统.首先,通过Hadoop云计算平台提供的分布式文件系统提升数据的存取速度,增强系统的容错性.在此基础上,利用MapReduce编程模型并行化数据流系综分类算法,提高数据的分类挖掘效率.最后,采用Web Service技术构建了SOA服务体系架构,从而整合了技术平台.测试结果表明,检测系统运行高效,并且检测精度高,具有一定的实用性和推广价值.     

面向服务的C2系统集成实现方式比较

分别简要概括了目前指控系统集成中主流的SOA实现方式,从实现方法、互操作性和服务质量等方面比较了CORBA、DCOM、RMI、Jini以及DDS实现方式在指控系统集成中的特点.分析了指控系统服务化实现的特点和需求,指出了当前各种实现方式在指控系统服务化集成中的优劣.提出了一种适用于分布式实时大容量数据交互环境下集成方式.     

Modeling a Dynamic Data Replication Strategy to Increase System Availability in Cloud Computing Environments

Failures are normal rather than exceptional in the cloud computing environments. To improve system avai- lability, replicating the popular data to multiple suitable locations is an advisable choice, as users can access the data from a nearby site. This is, however, not the case for replicas which must have a fixed number of copies on several locations. How to decide a reasonable number and right locations for replicas has become a challenge in the cloud computing. In this paper, a dynamic data replication strategy is put forward with a brief survey of replication strategy suitable for distributed computing environments. It includes: 1) analyzing and modeling the relationship between system availability and the number of replicas; 2) evaluating and identifying the popular data and triggering a replication operation when the popularity data passes a dynamic threshold; 3) calculating a suitable number of copies to meet a reasonable system byte effective rate requirement and placing replicas among data nodes in a balanced way; 4) designing the dynamic data replication algorithm in a cloud. Experimental results demonstrate the efficiency and effectiveness of the improved system brought by the proposed strategy in a cloud.     

基于云计算的IPTV业务平台架构设计及应用

随着云计算技术的飞速发展,特别是虚拟化技术、分布式存储系统的引入,催生了各种各样的服务及应用.本文首先介绍云计算的关键技术,包括虚拟化技术、分布式存储系统、分布式数据库.提出基于云计算的IPTV业务平台系统架构,分析其功能、技术优势及发展趋势.引入云计算技术,使得IPTV业务平台具有高可靠性、动态负载均衡能力和良好的扩展性,满足其业务快速增长的需求.     

移动云计算

在延伸云到网络边缘（终端）的趋势下,移动云计算正在成为一个新兴的云服务模型。它包括许多与用户密切相关移动设备。它们直接参与到很多云的工作中,使得云边界直接延伸到了整个物理网络系统中。在这篇文章中,我们将介绍什么是移动云计算,包括其范围,目前的发展和研究的挑战。     

Collaborative learning in the clouds

Cloud computing has emerged as one of the most highly discussed topics both in the academic community and in the computing industry. While most of the work that has been conducted to explore this field focuses either on establishing the basis for cloud computing or almost exclusively on the issues surrounding security and data privacy, this paper takes the first exploratory step into exploring the actual internal working of cloud computing and demonstrates its viability for organizations, more specifically educational establishments . The paper starts by introducing the most important key clouds computing concepts, including virtualization technologies, Web services and Service Oriented Architectures (SOA), and distributed computing. Light will be then shed on the impact and potential benefits of cloud computing on teaching and learning in educational institutions. The paper closes by describing building a private cloud inside educational institution and highlights its offerings for students, staff and lecturers.     

基于业务抽象规划的分布式动态服务组合算法

异构系统间难以实现计算资源的灵活共享,制约分布式信息系统性能的提升,基于面向服务架构的Web服务技术,为异构系统计算资源共享提供了有效手段。为此,针对Web服务组合在集中式发布架构下单点故障和性能瓶颈问题,提出一种基于业务抽象规划的分布式动态服务组合算法。该算法根据组合规划结果对业务抽象规划库进行动态扩充,快速组合出满足需求的服务,逐步提高服务组合响应率。仿真结果表明,该算法在分布式环境下可减少服务请求过程中交互的信息量,降低请求响应时间,提高服务组合效率。     

A new paradigm of cloud-based predictive maintenance for intelligent manufacturing

Advances in cloud computing reshape the manufacturing industry into dynamically scalable, on-demand service oriented, and highly distributed cost-efficient business model. However it also poses challenges such as reliability, availability, adaptability, and safety on machines and processes across spatial boundaries. To address these challenges, this paper investigates a cloud-based paradigm of predictive maintenance based on mobile agent to enable timely information acquisition, sharing and utilization for improved accuracy and reliability in fault diagnosis, remaining service life prediction, and maintenance scheduling. In the new paradigm, a low-cost cloud sensing and computing node is firstly developed with embedded Linux operating system, mobile agent middleware, and open source numerical libraries. Information sharing and interaction is achieved by mobile agent to distribute the analysis algorithms to cloud sensing and computing node to locally process data and share analysis results. Comparing to the commonly used client–server paradigm, the mobile agent approach enhances the system flexibility and adaptability, reduces raw data transmission, and instantaneously responds to dynamic changes of operations and tasks. Finally, the presented cloud-based paradigm of predictive maintenance is validated on a motor tested system.     

面向服务的云数据挖掘引擎的研究

数据挖掘算法处理海量数据时,扩展性受到制约。在商业和科学研究的各个领域,知识发现的过程和需求差异较大,需要有效的机制来设计和运行各种类型的分布式数据挖掘应用。提出了一种面向服务的云数据挖掘引擎的框架CloudDM。不同于基于网格的分布式数据挖掘框架,CloudDM利用开源云计算平台Hadoop处理海量数据的能力,以面向服务的形式支持分布式数据挖掘应用的设计和运行,并描述面向服务的云数据挖掘引擎系统的关键部件和实现技术。依据面向服务的软件体系结构和基于云平台的数据挖掘引擎,可以有效解决海量数据挖掘中的海量数据存储、数据处理和数据挖掘算法互操作性等问题。     

Dynamic cloud resource management for efficient media applications in mobile computing environments

Single-instruction-set architecture (Single-ISA) heterogeneous multi-core processors (HMP) are superior to Symmetric Multi-core processors in performance per watt. They are popular in many aspects of the Internet of Things, including mobile multimedia cloud computing platforms. One Single-ISA HMP integrates both fast out-of-order cores and slow simpler cores, while all cores are sharing the same ISA. The quality of service (QoS) is most important for virtual machine (VM) resource management in multimedia mobile computing, particularly in Single-ISA heterogeneous multi-core cloud computing platforms. Therefore, in this paper, we propose a dynamic cloud resource management (DCRM) policy to improve the QoS in multimedia mobile computing. DCRM dynamically and optimally partitions shared resources according to service or application requirements. Moreover, DCRM combines resource-aware VM allocation to maximize the effectiveness of the heterogeneous multi-core cloud platform. The basic idea for this performance improvement is to balance the shared resource allocations with these resources requirements. The experimental results show that DCRM behaves better in both response time and QoS, thus proving that DCRM is good at shared resource management in mobile media cloud computing.     

一种利用云环境实现Web服务组合容错的方法

随着Web服务迅猛发展,基于SOA的服务组合容错性研究成为了业界关注的焦点.服务组合中组件的失效,会导致整个组合执行失败,而资源不足、服务器负载过重是引发组件失效的主要原因之一.云计算作为一种新的计算泛型,其资源整合、动态分配的特点为解决传统SOA下因资源受限而引发的失效提供了新的容错思路.FTEL层将中间件技术应用到服务组合容错上,借助云环境完成服务替换,对传统SOA下较难解决的由于资源问题引起的组件失效进行了容错.