Using Java applets and CORBA for multi-user distributedapplications

The Java language environment, World Wide Web, and Common Object Request Broker Architecture are complementary software technologies, which when used together provide a powerful set of tools for developing and deploying multi-user distributed applications. We describe an approach to building reasonably sophisticated and easy-to-use client software as WWW-downloadable Java applets, which use CORBA to interact effectively with remote server software and thus coordinate and control access to a set of shared resources. We used this approach to reimplement a portion of an existing multi-user distributed application that had been built using the WWW Common Gateway Interface (CGI), then evaluated the differences between the two approaches. We found our method of combining Java applets and CORBA not only practical but in many ways superior to the widely used CGI approach, as well as to a conventional CORBA approach that does not exploit the WWW     

Secure execution of Java applets using a remote playground

Mobile code presents a number of threats to machines that execute it. We introduce an approach for protecting machines and the resources they hold from mobile code and describe a system based on our approach for protecting host machines from Java 1.1 applets. In our approach, each Java applet downloaded to the protected domain is rerouted to a dedicated machine (or set of machines), the playground, at which it is executed. Prior to execution, the applet is transformed to use the downloading user's Web browser as a graphics terminal for its input and output, and so the user has the illusion that the applet is running on his own machine. In reality, however, mobile code runs only in the sanitized environment of the playground, where user files cannot be mounted and from which only limited network connections are accepted by machines in the protected domain. Our playground thus provides a second level of defense against mobile code that circumvents language-based defenses. This paper presents the design and implementation of a playground for Java 1.1 applets and discusses extensions of it for other forms of mobile code, including Java 1.2     

Distributed Java applets for project management on the Web

The rapid evolution of our data communications infrastructure is making distributed projects increasingly viable. Without a common infrastructure, computer-supported collaborative tools for distributed teams have been prohibitively expensive to build and maintain. However, the increasing availability of the Internet is enabling companies to develop cost-effective collaborative solutions. Traditional desktop project management software is designed as a single-user tool that lets the project manager track tasks, milestones and deliverables. As teams spread over geographic distances with multiple centers of control, the communication, coordination, and tracking of ongoing project activity become key issues for project success. This article looks beyond the traditional planning focus of project management applications to a network-centric focus on collaboration. It describes the implementation of ActionPlan, a 100 percent Java-based application from Netmosphere that supports real-time collaboration among Java thin clients to facilitate distributed project management     

Merging ring-structured overlay indices: toward network-data transparency

Peer-to-peer index structures distributed and managed over the planet, commonly known as structured overlays (e.g., distributed hash tables) have been touted to play the role of a fundamental building block for internet-scale distributed systems. Traditional designs consider incremental or possibly even parallelized construction of a single overlay, which implicitly assumes global control and coordination to enforce the construction of an unique overlay. However, if merger of originally isolated overlays is made possible, then one can realize decentralized bootstrapping of overlays. So to say, smaller overlays can be constructed using any of the traditional mechanisms, which can then organically coalesce to form a larger overlay. Such self-organizational attributes of decentralized bootstrapping and organic growth are of paramount importance for large scale systems. In our previous works, we explained the challenges of merging important families of (tree and ring) structured overlays (Datta and Aberer in international workshop on self-organizing systems, 2006), and identified that tree structured overlays are relatively easier to merge in a transparent manner (Datta in IEEE international conference on self-adaptive and self-organizing systems, 2007). In this paper we investigate how ring structured overlays can be merged, both in terms of the necessary algorithms, as well as how it performs during the merger process, taking into account not only the ‘network’ merger process, but also looking into how and whether this process is ‘transparent’ for applications/end-users accessing and using the overlay as an index. We introduce interesting new metrics to evaluate the merger process and carry out asymptotic analysis for estimating the same, besides conducting simulation experiments to validate the theory as well as measure other aspects of the overlays’ performance under merger.     

Global teleporting with Java: toward ubiquitous personalizedcomputing

The essence of mobile computing is having your personal computing environment available wherever you happen to be. Traditionally, this is achieved by physically carrying a computing device (say, a laptop or PDA) which may have some form of intermittent network connectivity, either wireless or tethered. However, at the Olivetti and Oracle Research Laboratory, we have introduced another form of mobility in which it is the user's applications that are mobile. Users do not carry any computing platform but instead bring up their applications on any nearby machine exactly as they appeared when last invoked. We call this form of mobility teleporting, and it has been used continuously and fruitfully by many members of our laboratory. We are extending this idea from our LAN to the entire Internet using Java as the common interface. It is still our personal X sessions that are made mobile, but now they can appear anywhere on the Internet within any Java-enabled browser     

From objects to services: toward a stepwise migration approach for Java applications

Migrating legacy applications toward service-oriented systems is a hard task complicated by the lack of appropriate approaches and tools. In this paper, a stepwise approach is proposed to migrate a Java application into an equivalent application composed of a set of Web services invoked by an orchestrator. In each migration step, a portion of the target application is identified and migrated into a Web service. In this approach, the role of testing is central since after each migration step the new service-oriented application is tested with the aim of checking “its equivalence” with the original version. An experiment based on four Java applications has been conducted to tune the approach and evaluate applicability and effort involved in the migration process. The obtained results confirm the viability of the proposed approach and highlight some encountered SOA migration difficulties.     

Developing a Trojan applets in a smart card

This paper presents a method to inject a mutable Java Card applet into a smart card. This code can on demand parse the memory in order to search for a given pattern and eliminate it. One of these key features is to bypass security checks or retrieve secret data from other applets. We evaluate the countermeasures against this attack and we show how some of them can be circumvented and we propose to combine this attack with others already known.     

Java中的嵌入式SQL技术:SQLJ

SQLJ是访问数据库的一种技术，与JDBC相比，它具有很多优势，本文首先介绍了SQLJ的语法要点，然后分析了SQLJ程序的开发应用过程，最后对SQLJ与JDBC进行了比较，总结了各自的优点和不足。     

Leveraging human factors in cybersecurity: an integrated methodological approach

Cognition, Technology & Work - Computer and Information Security (CIS) is usually approached adopting a technology-centric viewpoint, where the human components of sociotechnical systems are...     

Security through Diversity: Leveraging Virtual Machine Technology

Biologists have long recognized the dangers of the lack of diversity or monocultures in biological systems. Recently, it has been noted that much of the fragility of our networked computing systems can be attributed to the lack of diversity or monoculture of our software systems. The problem is severe. Because it is virtually inevitable that software will ship with flaws, our software monoculture leaves systems open to large-scale attacks by knowledgeable adversaries. Inspired by the resilience of diverse biological systems, the authors developed the Genesis Software Development Toolchain. An innovative aspect of Genesis is the use of an application-level virtual machine technology that enables the application of diversity transforms at any point in the software toolchain. Using Genesis, they authors demonstrated that diversity, when judiciously applied, is a practical and effective defense against two widely used types of attacks—return-to-libc and code injection.     

State-set branching: Leveraging BDDs for heuristic search

In this article, we present a framework called state-set branching that combines symbolic search based on reduced ordered Binary Decision Diagrams (BDDs) with best-first search, such as A* and greedy best-first search. The framework relies on an extension of these algorithms from expanding a single state in each iteration to expanding a set of states. We prove that it is generally sound and optimal for two A* implementations and show how a new BDD technique called branching partitioning can be used to efficiently expand sets of states. The framework is general. It applies to any heuristic function, evaluation function, and transition cost function defined over a finite domain. Moreover, branching partitioning applies to both disjunctive and conjunctive transition relation partitioning. An extensive experimental evaluation of the two A* implementations proves state-set branching to be a powerful framework. The algorithms outperform the ordinary A* algorithm in almost all domains. In addition, they can improve the complexity of A* exponentially and often dominate both A* and blind BDD-based search by several orders of magnitude. Moreover, they have substantially better performance than BDDA*, the currently most efficient BDD-based implementation of A*.     

Easy Java Simulations: a software tool to create scientific simulations in Java

We introduce Easy Java Simulations, Ejs, a tool created by science teachers to help teach and learn science. Ejs allows users to create simulations using their knowledge of the scientific model. The author needs to supply a small amount of code for the model; the tool provides a graphical drag-and-drop interface to build the program. The resulting Ejs generated program is an independent, high quality Java application or applet ready to be published on a Web server. Ejs can serve as an effective teaching and learning tool if used in an appropriate pedagogical setting; for instance, to help students create their own simulations in order to express their conceptions on how a given scientific process works.The Ejs program and documentation can be freely downloaded from the site http://fem.um.es/Ejs.     

Leveraging resources in global software development

Leveraging global resources for software development is rapidly becoming the norm at Motorola, which has over 25 software development centers worldwide. Our project, called the 3G Trial (Third Generation Cellular System), was the first of its scope and significance developed by a global engineering team at Motorola. Staffing was the most significant issue we encountered in the 3G Trial. We had only about 20 percent of the required staff available at our division headquarters in Burlington Heights, Ill., US, and needed to find the other 80 percent to successfully complete the project. Early on, we concluded that our only means to staff the project was to rely on software development engineers from Motorola's worldwide software centers. We developed the system with staffing from six different countries. Next, we had to integrate the people into a team. While addressing this challenge, we identified key risk factors and developed approaches to reduce them. We separated the project risk factors into the five categories Carmel (1999) describes as the centrifugal forces that pull global projects apart. To pass on the lessons we learned from this project, this article sets out the global development issues we faced, our approaches to resolving them, and our findings compared to other research     

Leveraging parallel computing in multibody dynamics

At a time when sequential computing is limited to marginal year-to-year gains in speed, multi- and many-core architectures provide teraflop-grade performance to cost-conscious users. The ongoing shift to parallel computing spurs new research into solution methods that emphasize algorithmic concurrency. It also provides an opportunity to revisit complex real-life applications whose solutions have been until recently infeasible due to prohibitively heavy computational burdens. This paper concentrates on the use of commodity parallel computing in the field of multibody dynamics by illustrating how many-body frictional-contact dynamics, fluid–solid interaction analysis, and proximity computation have benefited from parallel computing. Preliminary results are encouraging and show one to two orders of magnitude reductions in simulation times. A set of open questions and final remarks round up the contribution.     

Java 3D—Java语言的三维图形解决方案

Java 3D是一种新型的三维图形编程方案,结合Java语言,在开发Internet及WWW上的三维图形网络应用有极大优势。本文介绍了Java3D API的特点,并结合一个利用Java 3D开发的实例说明其结构与编程模式。     

Bringing Java to the enterprise: Oracle on its Java server strategy

Java is becoming the predominant language for defining and deploying complex business logic across all tiers of the enterprise. Java is uniquely suited to distributed information systems, and clearly critical to the success of Oracle's network computing initiative. No other language combines the features required in these environments. This paper surveys five aspects of our Java product strategy. Unless otherwise stated, these components are included in the Oracle 8.1 software development kit, SDK2, which is under test at a small number of sites. Over the past 20 years, SQL has become the “shape” of the world's store of data. In many ways, Java represents a practical, ubiquitous means for augmenting this structure with the arbitrarily complex operational semantics that only a general-purpose, object-oriented programming language can provide. Such logic is inherently distributed, and may be freely deployed on any network computing tier. The combination of ubiquitous SQL data and Java behavior will generalize relational database management systems into the information servers that are so critical to the future of network computing