Distributed urban traffic applications based on CORBA event services

Intelligent transportation systems (ITS) in urban environments are based today on modern embedded systems with enhanced digital connectivity and higher processing capabilities, supporting distributed applications working in a cooperative manner. This paper provides an overview about modern cooperative ITS equipments and presents a distributed application to be used in an urban data network. As a case example, an application based on an embedded CORBA-compliant middleware layer and several computer vision equipments is presented. Results prove the feasibility of distributed applications for building intelligent urban environments

CosNamingFT - A Fault-Tolerant CORBA Naming Service

This paper describes the design and implementation of a fault-tolerant CORBA naming service - CosNamingFT. Every CORBA object is accessed through its Interoperable Object Reference (IOR), which is registered with the CORBA name service. The name service therefore is a critical gateway to all objects in a distributed system; to avoid having a single point of failure, the name service should be made fault-tolerant. CosNamingFT uses the GroupPac package [6], a CORBA-compliant suite of protocols, to replicate the name server. GroupPac services are built from Common Object Services that function as building blocks to implement fault-tolerant applications. This paper aims to demonstrate the usefulness of some of these object services and to demonstrate the importance of open solutions issues in replicating distributed objects

Experiências com tolerância a faltas no CORBA e extensões ao FT-CORBA para sistemas distribuidos de larga escala

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica.Esta tese apresenta nossas experiências com tolerância a faltas no CORBA e uma proposta de extensão das especificações Fault-Tolerant CORBA para sistemas distribuídos de larga escala. A motivação deste trabalho foi a inadequação ou a falta de definições nas especificações FT-CORBA que permitissem atender a requisitos de tolerância a falta para sistemas de larga escala, tal como a Internet. Neste trabalho é apresentado um conjunto de soluções, englobando detecção de falhas, membership e comunicação de grupo, que visam principalmente atender aspectos de escalabilidade, necessários quando são tratados sistemas desta natureza. A principal contribuição desta trabalho é a proposta de um modelo de hierarquia de domínios de tolerância a faltas que facilita o gerenciamento e comunicação de grupo interdomínio

Discuss And Fuse: Considering Modularity, Genericness, And Adaptation In The Development Of Consensus And Fault Detection Services

Although fault tolerant systems are badly needed, their development is not a trivial task. Considering fault tolerant distributed systems, this difficulty is even bigger, and any artifact that could make this task easier becomes highly valuable. In this paper, we propose and model a distributed consensus service and a fault detection service, namely, DisCusS and FuSe, that can be used as building blocks in the development of distributed fault tolerant applications. We also show the compliance of FuSe to FT-CORBA fault detection, and give some insights on the use of the proposed consensus service in a possible FT-CORBA implementation. 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