Monitoring distributed object and component communication

This thesis presents our work in the area of monitoring distributed software applications (DSAs). We produce three main results: (1) a design approach for building monitoring systems, (2) a design of a system for MOnitoring Distributed Object and Component Communication (MODOCC) behavior in middleware-based applications, and (3) a proof-of-concept implementation of this system

Integrated framework for development and execution of component-based Grid applications

Component-based software technologies have emerged as a modern approach to software development for distributed and grid applications. However, the lack of longer-term experience and the complexity of the target systems demand more research results in the field. This paper provides an overview of three different approaches to developing component- based grid applications. In order to re-use legacy codes, the wrapper software approach can be adopted in its two flavours - hand-written or automatically generated wrapper code. Another approach applicable to existing object-oriented software is to componentise the code by introducing appropriate modifications. The third approach is component-oriented development from scratch. We compare and contrast the three approaches and highlight their advantages and weaknesses

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 semi-formal comparison between the Common Object Request Broker Architecture (COBRA) and the Distributed Component Object Model (DCOM)

The way in which application systems and software are built has changed dramatically over the past few years. This is mainly due to advances in hardware technology, programming languages, as well as the requirement to build better software application systems in less time. The importance of mondial (worldwide) communication between systems is also growing exponentially. People are using network-based applications daily, communicating not only locally, but also globally. The Internet, the global network, therefore plays a significant role in the development of new software. Distributed object computing is one of the computing paradigms that promise to solve the need to develop clienVserver application systems, communicating over heterogeneous environments. This study, of limited scope, concentrates on one crucial element without which distributed object computing cannot be implemented. This element is the communication software, also called middleware, which allows objects situated on different hardware platforms to communicate over a network. Two of the most important middleware standards for distributed object computing today are the Common Object Request Broker Architecture (CORBA) from the Object Management Group, and the Distributed Component Object Model (DCOM) from Microsoft Corporation. Each of these standards is implemented in commercially available products, allowing distributed objects to communicate over heterogeneous networks. In studying each of the middleware standards, a formal way of comparing CORBA and DCOM is presented, namely meta-modelling. For each of these two distributed object infrastructures (middleware), meta-models are constructed. Based on this uniform and unbiased approach, a comparison of the two distributed object infrastructures is then performed. The results are given as a set of tables in which the differences and similarities of each distributed object infrastructure are exhibited. By adopting this approach, errors caused by misunderstanding or misinterpretation are minimised. Consequently, an accurate and unbiased comparison between CORBA and DCOM is made possible, which constitutes the main aim of this dissertation.ComputingM. Sc. (Computer Science

Technology transfer from HEP computing to the medical field: overview and application to dosimetry

We show how nowadays it is possible to achieve the goal of accuracy and fast computation response in radiotherapic dosimetry using MonteCarlo methods, together with a grid computing model. We present a complete, fully functional prototype system for brachytherapy, entirely based on open source software systems originally developed for High Energy Physics experiments. It integrates a Geant4-based simulation component, an AIDA-based dosimetric analysis, a web-based user interface, and distributed processing either on a local computing farm or on geographically spread nodes. Thanks to the object-oriented approach adopted for the architecture, the work presented can be easily extended to become a general purpose dosimetric system, capable to address all radiotherapic techniques. An extension for application to dosimetric studies for IMRT is in progress

ControlShell: A real-time software framework

The ControlShell system is a programming environment that enables the development and implementation of complex real-time software. It includes many building tools for complex systems, such as a graphical finite state machine (FSM) tool to provide strategic control. ControlShell has a component-based design, providing interface definitions and mechanisms for building real-time code modules along with providing basic data management. Some of the system-building tools incorporated in ControlShell are a graphical data flow editor, a component data requirement editor, and a state-machine editor. It also includes a distributed data flow package, an execution configuration manager, a matrix package, and an object database and dynamic binding facility. This paper presents an overview of ControlShell's architecture and examines the functions of several of its tools

Middleware Component Using Enterprise Java Bean (EJB)

Component-based software development promises to decrease software development and maintenance costs and also providing sophisticated facilities for software reuse. A component is a chunk of software that provides functionality such as login validation, customer transaction and calculation [3]. It is encapsulated which means, that it can only be accessed via its interface and can be combined with other systems [3]. Most of these characteristics are derived from object oriented development. Therefore this paper presents an overview and development of component based software using J2EE framework called Enterprise Java Bean (EJB). The aim of this proj ect is at capturing the middleware concept using EJB where this architecture provides loose coupling of presentation layer and business logic. Moreover, leads Having two different clients connecting to a single middleware component which resides in the container of J2EE Server. The details about design and development of this middleware component and testing this component on to a test bed called bookstore application is the heart of this project. This paper will also introduce about the advantage of EJB against distributed component model and the interoperability of this middleware component across different platform and programming languages

Design of a multi-threaded distributed telerobotic framework

A telerobotic system consists of master (client) and slave (server) stations which are usually connected by a computer network. A reliable real-time connection between master and slave systems is proposed using Distributed Components (.NET Remoting). This has a number of benefits such as software reusability, ease of extensibility, debugging, and data encapsulation. It is based on most advanced software tools like NET Framework that promise definite advantages over DCOM (Distributed Component Object Model) and RPC (Remote Procedure Call), previously used for distributed applications. The components communicate with each other using NET Remoting and SOAP (Simple Object Access Protocol) that automatically handle the network resources and data transfer while isolating the components from network protocol issues. This enhances the data security as well as facilitates easy deployment. Implementing telerobotics using the proposed approach gives the advantage of a multi-threaded execution needed to effectively realize multi-streaming of force, command and stereo data over a LAN