高性能计算服务环境应用编程接口

高性能计算服务环境主要面向用户、科研团队提供高性能计算服务.随着环境接入的超算中心以及应用社区和业务平台越来越多,超算中心以及社区和业务平台的用户希望能够使用原有账号登录高性能计算环境使用资源.高性能计算服务环境目前提供的应用编程接口仅支持通过LDAP认证的网格账号.为使得应用社区和业务平台用户使用自己原有的登录方式认证通过后就可访问高性能计算服务环境,我们重新设计开发了高性能计算服务环境应用编程接口.本文着重介绍新版应用编程接口的结构与部署实现,并通过用例来说明如何调用新版接口.新版接口为社区和业务平台接入高性能计算环境提供了更方便且安全地支撑.     

PETSc库在网格环境下的应用研究

网格计算的推广应用,需要各种资源和服务的支持,在自强2000集群系统上,采用基于OGSI的GT3网格技术。实现PETSc的网格服务,提供PETSc源程序的编译及PETSc并行作业的管理功能,用于在网格环境为远程用户解决各种复杂的科学计算问题。     

一种面向服务网格的通用框架及服务访问模型

网格资源的表示、组织、部署、发现、创建、使用和撤销是网格计算的重要研究问题,随着Webservices技术和服务网格理念的逐步成熟,以“服务”的方式来包装网格资源已经成为了一种趋势,并得到了网格界的一致认同。由于网格资源的“充足性”及“共享性”,采用池的方式来组织网格资源,以及把网格资源包装成服务,是一种很合理的方式。用户对网格的一次访问过程包括访问场景的创建,访问的实施,以及实施完成后的撤销,具有生命期的特征,而这正是虚拟组织所具有的功能,基于虚拟组织来设计服务访问模型是很合理的。基于物理资源池、服务池以及虚拟组织的思想,文章提出了面向服务网格的通用框架模型及服务访问模型VSP,VSP模型被用于指导HowU信息处理平台的设计。     

基于SAML和XACML的Web服务访问控制模型

Web服务采用了通用的协议和技术,便于用户访问,已成为了分布式计算的研究热点,但这种方便也带来了安全性的隐患。提出了一个基于SAML和XACML的Web服务访问控制模型,利用SAML协议实现单点登录,采用XACML策略描述语言对用户进行访问控制。模型在扩展SAML协议的基础上,把XACML引入Web服务能够更好地对服务端受保护资源进行控制,从而实现Web服务的安全访问控制。     

A high performance grid-web service framework for the identification of ‘conserved sequence tags’

The continuous increasing of computing power in biological research places a threshold to the single host use and suggests an approach based on distributed computing. An emerging solution is grid technology, which allows organization to make better use of existing computing resources by providing them with a single, transparent, aggregated source of computing power. Equally, bioinformatics analysis often involves many web services, allowing shared access to information and helping the biologist to design, describe, record complex experiments. A new generation of grid infrastructure, where web services are building blocks, allow managent of a web services workflow.This work shows a tool for the identification and functional annotation of ‘Conserved Sequence Tags’ (CSTs) through cross-species genome comparisons, deployed on a Grid System Architecture, based on Web Services concepts and technologies.     

基于Apache的动态Web内容缓存模块的实现

Web提供了访问远程信息资源便捷的方式,衡量Web服务质量的一个重要指标就是检索和获取信息所花费的时间。通过缓存服务器产生的动态内容可以避免对数据库重复的查询,减少用户对原始资源的访问密度,从而提高服务器的响应时间。文章介绍了Web服务器动态内容缓存模块的概念,优点,原理以及具体模块的实现流程。     

国家高性能计算环境资源评价规范研究

高性能计算资源作为科技创新的重要手段,是当代科技竞争的战略制高点,能集中体现一个国家的综合实力。国家高性能计算环境聚合了国内优秀的高性能计算资源,面向用户提供高效、便捷的高性能计算服务。为加强环境建设、提高服务质量,本文提出了一套可以量化网络服务水平和集群计算服务水平的规范,为高性能计算环境的准入提供理论依据,支持和引导用户合理使用资源,形成全局统筹的资源布局。本文首先提出对高性能计算资源服务水平的评价标准,针对资源的性能、可用性、安全性、可靠性、需求管理、技术支持和服务响应这些内容分别展开介绍。然后介绍了这些评价标准的计算方法,为评价标准的确立提供理论基础。最后以提出的资源评价标准为依据,对资源的分级标准进行制定并提出高性能计算环境的准入标准。     

Tasks of providing information security in distributed computing networks

The issue of providing information security for data and computing resources in grid networks is reviewed. Specific features of architecture of distributed computing networks based on grid platforms are analyzed. Security threats specific for grid systems are typified. The available measures ensuring security for grid systems are considered, and their drawbacks are indicated. The set of applied issues associated with ensuring grid protection from unauthorized access is defined.     

PGSW-OS: a novel approach for resource management in a semantic web operating system based on a P2P grid architecture

A web operating system is an operating system that users can access from any hardware at any location. A peer-to-peer (P2P) grid uses P2P communication for resource management and communication between nodes in a grid and manages resources locally in each cluster, and this provides a proper architecture for a web operating system. Use of semantic technology in web operating systems is an emerging field that improves the management and discovery of resources and services. In this paper, we propose PGSW-OS (P2P grid semantic Web OS), a model based on a P2P grid architecture and semantic technology to improve resource management in a web operating system through resource discovery with the aid of semantic features. Our approach integrates distributed hash tables (DHTs) and semantic overlay networks to enable semantic-based resource management by advertising resources in the DHT based upon their annotations to enable semantic-based resource matchmaking. Our model includes ontologies and virtual organizations. Our technique decreases the computational complexity of searching in a web operating system environment. We perform a simulation study using the Gridsim simulator, and our experiments show that our model provides enhanced utilization of resources, better search expressiveness, scalability, and precision.     

飞行器外型设计遗传优化算法的网格实现

飞行器外型设计遗传优化算法网格计算系统是基于网格技术的。该系统由一组网格服务所构成。遗传算法中的流场计算模块（CFD)在该系统中是以服务的方式提供并可运行在各种计算机上。在该系统中,能够动态地发现和利用计算机资源,这些资源可以是异构的机型,可以是不同操作系统,井且这些资源的位置也可以是广域分布的。这个系统,为飞行器外型设计提供了更加灵活的设计手段,比如对设计过程的监控和控制,多用户协作设计等。     

Context-aware service roaming for heterogeneous embedded devices over cloud

Cloud computing advocates a promising paradigm that facilitates the access within heterogeneous services, platforms, and end users. However, platforms (or host servers) have confined to devices which require a considerable computing resources. In this case, solutions concerning the efficient use of pervasive devices with constrained resources become an open issue. This study investigates the seamless connection between embedded devices and cloud resources to enhance the capability of computing and furthermore provide context-aware services. A method for wireless program dissemination and boot loading is proposed to transfer necessary information and resources between service and target device(s). The experiment results on time delay and energy cost demonstrate the feasibility and performance.     

用于教育资源管理的网格文件系统

基于Internet的远程教育是当今及未来教育的一种重要途径,它需要管理大量的教育资源及用户。在这样一个网格环境下,需要有一个具有高可扩展性、具有动态复制的分布式文件共享途径。该文在回顾了文件共享方面的相关工作之后,提出了一种基于Web的分布式文件管理架构——网格文件系统(GridFS)。描述了它的拓扑结构及文件访问服务和元信息服务。GridFS对许多网格应用、数字图书馆的互联和多级Web Cache系统是有益的。     

云计算系统可靠性研究综述

云计算作为一种新型计算模式,已经受到了学术界和工业界的广泛关注.基于资源虚拟化技术,云计算能够以按需使用、按使用量付费的方式为用户提供基础设施、平台、软件等服务.因此,越来越多的企业和组织选择云计算来部署他们的科学或商业应用.然而,随着用户数量的不断增加,数据中心的规模在迅速扩大、架构变得日益复杂,导致云计算系统的运行故障频繁发生,造成了巨大的损失.因此在规模巨大、架构复杂的云计算系统中,如何保障系统的可靠性已经成为一个极具挑战性的问题.针对云计算可靠性问题,概述了云计算系统中常见的各种故障,并详细描述了目前云计算中提高可靠性关键的故障管理技术;由于故障管理技术的应用会不可避免地增加系统的能耗,因此介绍了云计算中可靠性与能耗权衡问题的研究现状;最后列举了当前云计算可靠性研究中存在的主要挑战.     

基于WebGIS信息整合与利用的林业电子政务

林业电子政务要向社会公众提供专业服务。面向服务的架构和万维网地理信息系统是处理林业电子政务信息资源整合和利用的重要技术工具。文章以林业电子政务中森林火点检测的应用流程为例展示上述技术的运用方法。工作流程可以利用分布式的遥感数据、矢量辅助数据资源、森林火点检测算法和万维网地图发布服务,通过一个网格的基础架构把这些资源集成起来形成林业专业应用。文章展示的试验床用Web服务技术封装了专业算法。网格中间件采用的是自主研制的SIRGE,调度资源的工作流中间件采用的是自主研制的SIGApp,它们的专长是可以处理空间数据。用于通过这个试验床可以访问基于不同来源数据和服务得到的森林火点信息,为林业电子政务服务。     

Editorial: Internetware of the Age

While the infrastructure of computing shifting from isolated computers to Internet-linked resources, the software industry transfers its focus from computing products to dependable services. That''s one of the reasons why pervasive computing, grid computing, service computing and cloud computing are introduced on the open and dynamic Internet-linked platform. The communication abilities it introduced enable various resources exchanging and sharing freely, and participating in the community in the social network. There are three layers in such a platform: computing infrastructure, software services and information web. The underline layer, computing infrastructure, provides computing and communication facilities, and the surface layer, information web, is full of information recombination and consuming. The layer of software services serves as a factory to process constantly emerging and heterogeneous dynamic information using distributed, autonomous, and evolvable computing facilities. Therefore, services provided by such software systems should be adaptive, situational, trustworthy, autonomous and etc. To achieve flexible objectives, these services can be coordinated in various styles such as integration, cooperation, orchestration and etc. A portmanteau term \Internetware" is used     

一种基于Linux容器技术的大规模遥感数据云服务平台

遥感数据云服务平台是基于云计算技术,整合大规模遥感数据的存储资源和计算资源,实现资源共享和按需使用的服务模式的地理信息处理服务平台。我们基于分布式存储技术实现遥感数据的高效存储、Linux 容器技术实现快速部署和资源隔离、ownCloud 私有云技术实现高效共享和 IPythonnotebook 交互式技术实现方便易用交互,设计了一种稳定、高效的地理信息云服务平台。用户可通过Web的方式方便的访问大规模遥感数据,并利用云主机的计算、存储资源对所需的遥感数据进行分析和处理。     

A specification model for context-based collaborative applications

This paper presents a model for building context-based systems in pervasive computing environments from high level specifications. A pervasive computing environment is viewed as a collaboration space consisting of mobile users, system services, and sensors and resources embedded in the physical environment. The approach presented here is developed for building collaborative activities in which users and environment services cooperate towards some shared objectives and tasks. The specification model allows expression of policies related to context-based discovery and secure access of resources, and role-based interactions among users and environmental services. Using several examples we illustrate the capabilities of our specification model for expressing various kinds of context-based requirements for resource access and user interactions.     

Integrate software agents and CORBA in computational grid

This paper presents an Agent-based Computational Grid (ACG), which applies the concept of CORBA and agent to computational grid. The ACG system is used to implement a uniform higher level management of the computing resources and services on the Grid, and provide users with a consistent and transparent interface for accessing such services. In ACG grid, grid services are implemented by CORBA or by grid agent. Grid agents and CORBA objects will interact with each other to achieve user's service request. Our solution is the creation of a bridge between the CORBA and grid agents. The solution provides with the opportunity of considering an agent as a CORBA service and accessing CORBA services even from a grid agent. Thus, in AGC grid, existing legacy systems can be easily exploited as grid services. In this paper, firstly, the features of ACG grid are described, and then the design and implementation are given. Finally, some conclusions are given.     

一种基于Web浏览器的分布式应用系统的构造方法

文章提出了一种利用Web浏览器插入程序(Plug-in)构造紧耦合的分布式应用系统的方法.该 方法适合于开发在因特网上或企业网内部运行的以数据处理为主的分布式应用系统.它充分 利用Web浏览器的功能,使得用户可以利用本地结点计算资源,方便地访问并加工远程结点或 本地结点的数据.文章通过举例说明了构造这类系统的方法.     

Wireless network extension using mobile IP

Over the last two decades, we have seen a dramatic shift in computing systems, away from the monolithic mainframe and toward increasingly distributed, client-server systems. One of the key elements enabling the success of the distributed computing environment was the interconnecting network technology. High-speed, reliable network hardware and protocols evolved to support client-server applications. Network technology has now progressed to the point that applications are being written to specifically exploit the capabilities of the network. The explosion of World Wide Web applications is the latest example of the fact that the network is now the focus of the distributed computing environment. In a concurrent development, personal computing platforms placed increasingly powerful systems in ever smaller form factors. Users have embraced these advances: Mobile computers, in the form of laptops, palmtops, and personal digital assistants (PDAs), are a significant element of the current computing environment. However, to be fully productive, the mobile computer user requires access to the network. Further, access to a network is not sufficient. Mobile users need access to the same network-the same resources and services and communications capabilities-that they would if they were at their desktops. We refer to this concept of providing home network access to the mobile user as network extension. Addressing many requirements for practical wireless access, this Internet technology aids the development of advanced data services for wireless networks, including the integrated dispatch enhanced network