“网络计算模式与Java技术”的应用前景

“网络计算模式”对信息科学和技术的发展，甚至人类社会生活都产生了无法估量的影响，而Ｊａｖａ技术的应用更使得网络计算模式如虎添翼。此外，文中还阐述了在Ｉｎｔｅｒｎｅｔ上进行多层次研究与开发的思路。     

Java安全机制下移动Agent系统的安全性问题

移动Agent作为分布式网络计算的一种新形式,可以降低网络传输量,异步地完成任务。但在复杂的网络环境下,移动Agent对安全性提出了特殊的要求。文中先大致介绍了移动Agent所带来的安全隐患,然后深入地研究了Java语言的安全机制,最后给出了一个安全模型的参考实现,并讨论如何结合Java的安全模型来解决移动Agent的安全性问题。虽然Java的安全模型本身存在一些不完善的地方,但随着其进一步改进,安全模型参考实现也将为移动Agent的应用提供更有力的保障。     

移动中间件：移动无线Internet的将来

移动计算正成为一个迅速发展的领域。然而由于移动环境的种种限制,为开发移动应用带来巨大的挑战。文章讨论解决此问题的一种新兴技术：移动中间件技术,并提出一个移动中间件的实际应用体系结构,为移动终端设备提供一种简单、安全的方法访问已存在的分布式对象系统。     

Java移动代码的授权访问研究

Java移动代码是一种可以通过网络从一台计算机传珐另一台计算机上运行的Ｊava程序,在现代网络计算及电子商务中具有广泛应用,Ｊava的这一显著特性也蕴藏着授权管理上的不足,未授权者可以很容易地非法使用这些程序,针对Ｊava移动代码的这些不足之处,分别对Ｊava Applet及Ｊava Applet及Ｊava Servlet提出了基于数字签名算法的授权与访问控制方案,安全,有效地解决了这种新兴的授权与访问控制问题。     

基于 REST 风格的科学计算环境 Web服务 API

基于 Web 页面的计算门户提供了简单易用的用户使用界面,这些门户需要访问异构的计算机群。本文研究和实现基于 REST 风格的科学计算环境 Web 服务 API (SCEAPI-REST),其核心思想是充分利用 Web 服务在复杂系统中的集成优势以及 REST 风格的 API 跨平台和跨编程语言的特性,为开发者提供简单易用的计算机群开发接口,包括用户管理、资源查询、作业管理和文件传输等功能。基于 SCEAPI-REST,开发人员不再需要解决机群访问的繁杂问题,只需要专心构建面向科学计算的终端软件。该 API 已经应用到计算化学、材料科学、生物信息等多个领域的专业社区和工具软件。     

From smart to autonomous phones

As smart phones offer more options, driving new applications development, we need to establish appropriate new standards. Here, we review existing related standards, focusing on two missing features that fully autonomous phones will require. The common Java standard for building enterprise class applications is the Java 2 platform, Enterprise Edition. J2EE supports a rich set of APIs, and many vendors provide implementations of those APIs for programming Web services.     

Provisioning of energy consumption information for mobile ads

Advertisement-embedded mobile applications have been reported to consume a non-trivial amount of energy. Although a few studies have focused on the energy consumption of mobile advertisements (ads), no previous work has addressed the mobile ad ecosystem, which consists of users, application developers, and ad providers. In this paper, we define the advertisement energy information (AEI) required for the mobile ad ecosystem, and we propose a set of application programming interfaces (APIs) to provide AEI that considers various requirements of the underlying ecosystem. To realize the APIs, we developed a system service in Android to collect the AEI accurately and with low overhead. The experiment results show the validity of the proposed scheme, and the case studies demonstrate the usefulness of the proposed APIs.     

Network Application Programming Interface over Session Initiation Protocol,a novel approach to the global roaming environment

Session Initiation Protocol (SIP) is the most favorable candidate as the mobility management protocol in mobile computing. However, both the application and its developer suffer from inconveniences in utilizing SIP due to lack of a universal interface of SIP. In this paper, the Network Application Programming Interface over Session Initiation Protocol (NAPISIP) is proposed to facilitate using SIP in applications. The NAPISIP has the advantages of supporting concurrent mobility, avoiding application modification, saving application developers from burdens of learning to use SIP, and freeing operating systems from requirements of supporting sophisticated services or Application Programming Interfaces (APIs) to get communication handoff information. The NAPISIP is implemented on Windows 2000 and given experiments. In the experiments with legacy computers, the NAPISIP not only shows a promising performance but also has no drawbacks in Mobile IP when mobile hosts roam through networks.     

结合生活知识辅助计算机网络理论教学的方法

结合生活知识辅助"计算机网络"理论教学,是一种新的教学尝试。把计算机网络中计算机之间的通信过程类比人类的通信过程,可以让学生深刻理解计算机网络的理论知识,取得事半功倍的效果。本文给出结合生活知识辅助计算机网络理论教学的思路,探讨内容包括网络协议层次与人类通信所使用协议层次的类比、身边计算机网络协议与层次在哪里、RIP路由协议水平分割的教学设计、三层交换技术的教学设计,收到良好的教学效果。     

Teaching secure programming

Computer users, managers, and developers agree that we need software and systems that are "more secure". Such efforts require support from both the education and training communities to improve software assurance -particularly in writing secure code.     

城域网考试系统发布方式研究

本文综合ActiveX、Java Applet、Java Web Start以及一些知名公司的软件发布方法．提出了新的城域网考试系统发布策略,使城域网考试系统的发布大大简化．采用三层发布技术和替代容器,使网络带宽占用减少90%以上,并且客户端可以脱离浏览器运行。对于开发高效率B／S体系的应用程序的发布来说,很有参考价值和借鉴意义。     

Network Resource Awareness and Control in Mobile Applications

As mobile devices become increasingly capable of simultaneously using various kinds of wireless and fixed networks, developers must match mobile application needs to network resource dynamics. The authors' network resource model and network abstraction layer (NAL) software offer an extensible network resource abstraction to applications running on mobile devices. The NAL service can be used in conjunction with well-known APIs, such as the Socket API, which provide access to these resources; it also accommodates support for mobility-management facilities, such as mobile IP, if available     

Klava: a Java package for distributed and mobile applications

Highly distributed networks have now become a common infrastructure for wide‐area distributed applications whose key design principle is network awareness, namely the ability to deal with dynamic changes of the network environment. Network‐aware computing has called for new programming languages that exploit the mobility paradigm as a basic interaction mechanism. In this paper we present the architecture of KLAVA , an experimental Java package for distributed applications and code mobility. We describe how KLAVA permits code mobility by relying on Java and present a few distributed applications that exploit mobile code programmed in KLAVA . Copyright © 2002 John Wiley & Sons, Ltd.     

基于工作过程的计算机网络技术专业课程体系建设与改革探索

针对目前计算机网络技术专业学生对专业课程学习存在迷惑性认识而导致的学习动力不足,为提高计算机网络技术专业学生就业率,对计算机网络技术专业课程体系建设进行了基于工作过程导向1的改革尝试,经过三年的努力,取得了初步的成效。．     

移动智能终端平台基于行为的远程证明方案

移动智能终端平台集通信、社交、网上购物、娱乐等众多功能于一身,恶意程序对相关服务的破坏可能威胁到用户财产和个人隐私的安全. 远程证明是可信计算的核心功能之一,它使得移动智能终端能向远程服务提供方证明平台运行状态的安全性. 传统的远程证明方案主要应用于计算机平台,无法很好的适应软件频繁更新、多方服务共同运行的移动智能终端环境. 针对移动智能终端环境的特点,本文设计了一种基于行为的远程证明方案,通过软件开发人员定义软件行为列表,终端系统强制实施行为限制,服务提供方自定义策略对终端环境进行验证的方式,满足了服务提供方保障其服务安全运行的需求. 方案原型的实现和评估表明本文方案兼具较强的安全能力和较高的性能.     

Wireless security's future

Standards bodies and industry organizations are spending a great deal of time and money on developing and deploying next-generation solutions that address growing wireless network security problems. The 802.11i IEEE draft standard provides next-generation authentication, authorization, and encryption capabilities. The WiFi Alliance, a wireless industry organization, has jumped the gun and created the WiFi Protected Access (WPA) standard, a subset of the 802.11i draft. These new standards are more complicated than their predecessors but are more scalable and secure than existing wireless networks. They also dramatically raise the bar for attackers and administrators. The new standards will employ a phased adoption process because of the large installed base of 802.11 devices. Proper migration to 802.11i and mitigating the legacy wireless risks will be a bumpy road. However, the end result will provide users a secure base for mobile computing needs.     

Internet Network Resource Information Model

The foundation of any network management systems is a database that contains information about the network resources relevant to the management tasks.A network information model is an abstraction of network resources,including both managed resources and managing resources,In the SNMP-based management framework,management information is defined almost exclusively from a “Device“ viewpoint,namely managing a network is equivalent to managing a collection of individual nodes.Aiming at making use of recent advances in distributed computing and in object-oriented analysis and design,the Internet management architecture can also be based on the Open Distributed Processing Reference Model(RM-ODP).The purpose of this article is to provide an Internet Network Resource Information Model.First,a layered management information architecture will be discussed.Then the Internet Network resource information model is presented.The information model is specified using object-Z.     

基于普适计算的文化网格

普适计算是一种将嵌入式系统、网络计算、移动计算技术相结合形成一个以人为本的信息服务智慧空间环境,人们能够在智慧空间中自由活动,享受无所不在的信息服务。网格计算的目标是使得网络上的各种资源能象电力网络一样将计算和信息的使用变得简单易用。在普适计算与网格计算的支持下,智慧空间可以不断拓展成为按需服务的信息文化基础设施网格,即文化网格。探讨了文化网格的体系结构、层次模型及关键技术。