<p>The aim of this work is to design an experiment, where client-server systems can be compared. They belong to the group of systems that are called component systems. Client-server systems are difficult to compare, because they are complex. The client-server systems are documented in different ways. Notations in the implementation of them are in different ways. There is a large difference in the communication between the client and server. The architectures between the client-server systems differ also, but they are not totally different. Therefore it is possible to construct an experiment for comparing them. Client-server systems that will be compared are Java RMI, Web Services, CORBA, and Enterprise JavaBeans. We are going to use Java as the programming language. Some of these systems, for example CORBA, can be implemented in other languages. The designed experiment is among other things going to answer how long time is needed to implement a specific application, how fast a specific client-server system is, and how long time is spent for learning about a specific system.</p>

Konstanz, FH, Diplomarb., 2005.

Techn. Hochsch., Diss., 2000--Aachen.

Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2005 / Inclui bibliografia / RPC (Chamada de Procedimento Remoto) tornou-se um dos mais poderosos paradigmas de comunicação para sistemas distribuídos. Recentemente, linguagens orientadas a objetos têm causado grande impacto na semântica do RPC, com um grande número de variações, com

The main objective of this work is to inform the reader of the communication protocols Modbus TCP and Modbus RTU and create an embedded device based on the microprocessor STM32 capable of conversion between Modbus RTU and Modbus TCP protocols. The device should be capable of simple first run configuration with simple user interface.

Diploma thesis deals with an anonymous transmit of messages using protocol for anonymous authentication. In first part, we introduce theoretical familiarization to the issues and description protocol for anonymous authentication. Further, it describes the suggestion of the communication between the client and the server. Finally, contains a description of the created system for anonymous transmit of messages, which consists of the server and clients, who can leave challenges on the server for other users and they obtains challenges from the server. The thesis explains how to start and control program. There are also discussed methods of computing verification values, encryption keys and messages and authentication of receivers.

The goal is to design and to implement a library for developing Java applications controlled over WWW. This library provides a virtual graphical user interface and it implements the network communication with a real remote graphical user interface. The remote graphical user interface is implemented as a Java applet. The proposed solution is based on the Remote Method Invocation (RMI) framework that provides the communication between the applet and the application running on the server.

Made available in DSpace on 2016-06-02T19:06:00Z (GMT). No. of bitstreams: 1 4732.pdf: 3415662 bytes, checksum: 0b118a8a41e64b0a67c7b0956df6d970 (MD5) Previous issue date: 2012-09-12 / Universidade Federal de Sao Carlos / Immersive, interactive, and collaborative distributed applications, due to their real time and multi-platform characteristics, require a monitoring structure of their functionalities during the development period, which is not fully available in the current monitoring systems, which are usually specific of the languages and platforms in which they are made available. Monitoring systems that require synchronism of distributed objects during the processing is a complex task. Especially in distributed systems from multi-projection where timing is critical to its operation. It is often difficult to check the correct execution of the system. It might be useful for developers and users of such systems to have the ability of identifying, for example, if the reason for the system delay is due to the abusive use of a resource or due to programming mistakes; the identification of which object has crashed, compromising the system as a whole. Distributed object systems, also known as SOA (Service Oriented Architecture), generally use middleware of the broker type in their infrastructure and can have a dynamic number of connected clients or servers when running. There are, in the literature, several tools for the monitoring of performance, resources, debugging, and support, among others, of such systems. Nevertheless, the tools available in the literature are limited to programming languages or platforms that are able to process the monitoring agents related to them. In this work, a tool for the monitoring of distributed object systems is proposed, based on communication described in XML documents, which allows language and platform independence in the such systems development. A structure for the design of tools for the monitoring of distributed object systems is proposed, based on communication described in XML documents, which allows language and platform independence in the such systems development. In addition to the structure that is theoretically founded, the conception of a tool is structured in the manner described and proven in monitoring data from a case study. / Aplicações Distribuídas Imersivas, Interativas e Colaborativas, dadas suas características de tempo real e multiplataformas, demandam uma estrutura de monitoramento de suas funcionalidades, não plenamente disponíveis nos sistemas atuais de monitoramento, em geral específicos das linguagens e plataformas em que são disponibilizadas. Monitorar sistemas que necessitam de sincronismo no processamento de objetos distribuídos é uma tarefa complexa. Principalmente em sistemas distribuídos e de multiprojeção, onde o sincronismo é fundamental para seu funcionamento. Muitas vezes, é difícil apurar o correto funcionamento dos mesmos. Pode ser útil a desenvolvedores e usuários de tais sistemas a capacidade de se identificar, por exemplo, se a lentidão do sistema está sendo ocasionada por: uso abusivo de um recurso; por um erro na programação de um objeto ou; a identificação de qual objeto travou, comprometendo o sistema como um todo. Sistemas de objetos distribuídos, também conhecidos como SOA (Service Oriented Archtecture), geralmente utilizam mediadores do tipo broker em sua infraestrutura e podem ter um número dinâmico de clientes ou servidores conectados quando estão em execução. Existem na literatura diversas ferramentas destinadas ao monitoramento de performance, recursos, depuração, auxílio, manutenção de tais sistemas, etc. Porém, as ferramentas encontradas na literatura são restritas a linguagens ou plataformas que possam processar os agentes de monitoramento vinculados às mesmas. Neste trabalho, é proposta uma estrutura para a concepção de ferramentas para o monitoramento de sistemas de objetos distribuídos baseados em comunicações descritas em documentos XML, o que permite independência de linguagem ou plataforma na concepção de tais sistemas. Além da estrutura que é teoricamente fundamentada, a concepção de uma ferramenta nos moldes estruturados é descrita e provada no monitoramento de um estudo de caso.

<p>A Transaction Reproduction System (ARTSY) is a distributed system that enables secure transactions and reproductions of digital content over an insecure network. A field of application is reproductions of visual arts: A print workshop could for example use ARTSY to print a digital image that is located at a remote museum. The purpose of this master thesis project was to propose a specification for ARTSY and to show that it is technically feasible to implement it. </p><p>An analysis of the security threats in the ARTSY context was performed and a security model was developed. The security model was approved by a leading computer security expert. The security mechanisms that were chosen for the model were: Asymmetric cryptology, digital signatures, symmetric cryptology and a public key registry. A Software Requirements Specification was developed. It contains extra directives for image reproduction systems but it is possible to use it for an arbitrary type of reproduction system. A prototype of ARTSY was implemented using the Java programming language. The prototype uses XML to manage information and Java RMI to enable remote communication between its components. It was built as a platform independent system and it has been tested and proven to be operational on the Sun Solaris platform as well as the Win32 platform.</p>

A Transaction Reproduction System (ARTSY) is a distributed system that enables secure transactions and reproductions of digital content over an insecure network. A field of application is reproductions of visual arts: A print workshop could for example use ARTSY to print a digital image that is located at a remote museum. The purpose of this master thesis project was to propose a specification for ARTSY and to show that it is technically feasible to implement it. An analysis of the security threats in the ARTSY context was performed and a security model was developed. The security model was approved by a leading computer security expert. The security mechanisms that were chosen for the model were: Asymmetric cryptology, digital signatures, symmetric cryptology and a public key registry. A Software Requirements Specification was developed. It contains extra directives for image reproduction systems but it is possible to use it for an arbitrary type of reproduction system. A prototype of ARTSY was implemented using the Java programming language. The prototype uses XML to manage information and Java RMI to enable remote communication between its components. It was built as a platform independent system and it has been tested and proven to be operational on the Sun Solaris platform as well as the Win32 platform.