The SATIN component system - a metamodel for engineering adaptable mobile systems

Mobile computing devices, such as personal digital assistants and mobile phones, are becoming increasingly popular, smaller, and more capable. We argue that mobile systems should be able to adapt to changing requirements and execution environments. Adaptation requires the ability-to reconfigure the deployed code base on a mobile device. Such reconfiguration is considerably simplified if mobile applications are component-oriented rather than monolithic blocks of code. We present the SATIN (system adaptation targeting integrated networks) component metamodel, a lightweight local component metamodel that offers the flexible use of logical mobility primitives to reconfigure the software system by dynamically transferring code. The metamodel is implemented in the SATIN middleware system, a component-based mobile computing middleware that uses the mobility primitives defined in the metamodel to reconfigure both itself and applications that it hosts. We demonstrate the suitability of SATIN in terms of lightweightedness, flexibility, and reusability for the creation of adaptable mobile systems by using it to implement, port, and evaluate a number of existing and new applications, including an active network platform developed for satellite communication at the European space agency. These applications exhibit different aspects of adaptation and demonstrate the flexibility of the approach and the advantages gaine

Migration from client/server architecture to internet computing architecture

The Internet Computing Architecture helps in providing a object-based infrastructure that can be used by the application developers to design, develop, and deploy the ntiered enterprise applications and services. For years of distributed application development, the Internet Computing Architecture has helped in providing various techniques and infrastructure software for the successful deployment of various systems, and established a foundation for the promotion of re-use and component oriented development. Object-oriented analysis is at the beginning of this architecture, which is carried through deploying and managing of finished systems. This architecture is multi-platform, multi-lingual, standards-based, and open that offers unparalleled integration capability. And for the development of mission critical systems in record time it has allowed for the reuse of the infrastructure components. This paper provides a detailed overview of the Internet Computing Architecture and the way it is applied to designing systems which can range from simple two-tier applications to n-tier Web/Object enterprise systems. Even for the best software developers and managers it is very hard to sort through alternative solutions in today\u27s business application development challenges. The problems with the potential solutions were not that complex now that the web has provided the medium for large-scale distributed computing. To implement an infrastructure for the support of applications architecture and to foster the component-oriented development and reuse is an extraordinary challenge. Further, to scale the needs of large enterprises and the Web/Internet the advancement in the multi-tiered middleware software have made the development of object-oriented systems more difficult. The Internet Computing Architecture defines a scaleable architecture, which can provide the necessary software components, which forms the basis of the solid middleware foundation and can address the different application types. For the software development process to be component-oriented the design and development methodologies are interwoven. The biggest advantage of the Internet Computing Architecture is that developers can design object application servers that can simultaneously support two- and three-tier Client/Server and Object/Web applications. This kind of flexibility allows different business objects to be reused by a large number of applications that not only supports a wide range of application architectures but also offers the flexibility in infrastructure for the integration of data sources. The server-based business objects are managed by runtime services with full support for application to be partitioned in a transactional-secure distributed environment. So for the environments that a supports high transaction volumes and a large number of users this offers a high scaleable solution. The integration of the distributed object technology with protocols of the World Wide Web is Internet Computing Architecture. Alternate means of communication between a browser on client machine and server machines are provided by various web protocols such as Hypertext Transfer Protocol and Internet Inter-ORB Protocol [NOP]. Protocols like TCP/IP also provides the addressing protocols and packetoriented transport for the Internet and Intranet communications. The recent advancements in the field of networking and worldwide web technology has promoted a new network-centric computing structure. World Wide Web evolves the global economy infrastructure both on the public and corporate Internet\u27s. The competition is growing between technologies to provide the infrastructure for distributed large-scale applications. These technologies emerge from academia, standard activities and individual vendors. Internet Computing Architecture is a comprehensive, open, Network-based architecture that provides extensibility for the design of distributed environments. Internet Computing Architecture also provides a clear understanding to integrate client/server computing with distributed object architectures and the Internet. This technology also creates the opportunity for a new emerging class of extremely powerful operational, collaboration, decision support, and e-commerce solutions which will catalyze the growth of a new networked economy based on intrabusiness, business -to-business (B2B) and business-to-consumer (B2C) electronic transactions. These network solutions would be able to incorporate legacy mainframe systems, emerging applications as well as existing client/server environment, where still most of the world\u27s mission-critical applications run. Internet Computing Architecture is the industry\u27s only cross-platform infrastructure to develop and deploy network-centric, object-based, end-to-end applications across the network. Open and de facto standards are at the core of the Internet computing architecture such as: Hyper Text Transfer Protocol (HTTP)/ Hyper Text Markup Language (HTML)/ Extensible Markup Language (XML) and Common Object Request Broker Architecture (CORBA). It has recognition, as the industry\u27s most advanced and practical technology solution for the implementation of a distributed object environment, including Interface Definition Language (IDL) for languageneutral interfaces and Internet Inter Operability (MOP) for object interoperability. Programming languages such as JAVA provides programmable, extensible and portable solutions throughout the Internet Computing Architecture. Internet Computing Architecture not only provides support, but also enhances ActiveX/Component Object Model (COM) clients through open COM/CORBA interoperability specifications. For distributed object-programming Java has also emerged as the de facto standard within the Internet/Intranet arena, making Java ideally suited to the distributed object nature of the Internet Computing Architecture. The portability that it offers across multi-tiers and platforms support open standards and makes it an excellent choice for cartridge development across all tiers

A scalable application server on Beowulf clusters : a thesis presented in partial fulfilment of the requirement for the degree of Master of Information Science at Albany, Auckland, Massey University, New Zealand

Application performance and scalability of a large distributed multi-tiered application is a core requirement for most of today's critical business applications. I have investigated the scalability of a J2EE application server using the standard ECperf benchmark application in the Massey Beowulf Clusters namely the Sisters and the Helix. My testing environment consists of Open Source software: The integrated JBoss-Tomcat as the application server and the web server, along with PostgreSQL as the database. My testing programs were run on the clustered application server, which provide replication of the Enterprise Java Bean (EJB) objects. I have completed various centralized and distributed tests using the JBoss Cluster. I concluded that clustering of the application server and web server will effectively increase the performance of the application running on them given sufficient system resources. The application performance will scale to a point where a bottleneck has occurred in the testing system, the bottleneck could be any resources included in the testing environment: the hardware, software, network and the application that is running. Performance tuning for a large-scale J2EE application is a complicated issue, which is related to the resources available. However, by carefully identifying the performance bottleneck in the system with hardware, software, network, operating system and application configuration. I can improve the performance of the J2EE applications running in a Beowulf Cluster. The software bottleneck can be solved by changing the default settings, on the other hand, hardware bottlenecks are harder unless more investment are made to purchase higher speed and capacity hardware

The simplicity project: easing the burden of using complex and heterogeneous ICT devices and services

As of today, to exploit the variety of different "services", users need to configure each of their devices by using different procedures and need to explicitly select among heterogeneous access technologies and protocols. In addition to that, users are authenticated and charged by different means. The lack of implicit human computer interaction, context-awareness and standardisation places an enormous burden of complexity on the shoulders of the final users. The IST-Simplicity project aims at leveraging such problems by: i) automatically creating and customizing a user communication space; ii) adapting services to user terminal characteristics and to users preferences; iii) orchestrating network capabilities. The aim of this paper is to present the technical framework of the IST-Simplicity project. This paper is a thorough analysis and qualitative evaluation of the different technologies, standards and works presented in the literature related to the Simplicity system to be developed

Forum Session at the First International Conference on Service Oriented Computing (ICSOC03)

The First International Conference on Service Oriented Computing (ICSOC) was held in Trento, December 15-18, 2003. The focus of the conference ---Service Oriented Computing (SOC)--- is the new emerging paradigm for distributed computing and e-business processing that has evolved from object-oriented and component computing to enable building agile networks of collaborating business applications distributed within and across organizational boundaries. Of the 181 papers submitted to the ICSOC conference, 10 were selected for the forum session which took place on December the 16th, 2003. The papers were chosen based on their technical quality, originality, relevance to SOC and for their nature of being best suited for a poster presentation or a demonstration. This technical report contains the 10 papers presented during the forum session at the ICSOC conference. In particular, the last two papers in the report ere submitted as industrial papers

Integration of Internet and Telecommunications- An Architecture for Hybrid Services

In this article, we propose an architecture for hybrid services, i.e., services that span many network technologies, such as the Public Switched Telephone Network (PSTN), cellular networks and networks based on the Internet Protocol (IP). These services will play an important role in the future because they leverage on the existing infrastructures, rather than requiring new and sophisticated mechanisms to be deployed. We explore a few issues related to hybrid services and propose a platform, as well as a set of components, to facilitate their creation and deployment. The existing infrastructure is only required to generate specific events when requests for hybrid services are detected. We present the design of a service layer, based on Java, that handles the treatment of these special requests. Our service layer is provided with a set of generic components realized according to the JavaBeans model. We illustrate the strength of our architecture by discussing two hybrid-service examples: a calendar service and a call forwarding service

Telecommunication Services Engineering- Definitions, Architectures and Tools

This paper introduces telecommunication services engineering through a definition of services, of network architectures that run services, and of methods, techniques and tools used to develop services. We emphasize the Intelligent Network (IN), the Telecommunication Management Network (TMN) and TINA architecture

Component-Based Development Using UML

Component-based software development (CBD) is a potential breakthrough for software engineering. Unified Modeling Language (UML) can potentially facilitate CBD design and modeling. Although many research projects concentrate on the conceptual interrelation of UML and CBD, few incorporate actual component frameworks into the discussion, which is critical for real-world software system design and modeling. This paper reviews component-based development, including the use of UML for modeling CBD. The paper then discusses the means by which UML extension mechanisms can be used to better support the popular component framework -- CORBA. Two other important component frameworks, DCOM and Web Services, are also discussed