Toggle Main Menu Toggle Search

Open Access padlockePrints

Building Responsive and Reliable Distributed Services: Models and Design Options

Lookup NU author(s): Dr Paul Ezhilchelvan

Downloads


Abstract

This paper is a part of the document which my colleagues and I prepared for the National Air Traffic control System (NATS), UK, to highlight the problem areas involved in the design, development, implementation, upgrade and management of safety critical distributed systems. NATS monitors and decides the flight paths of civilian aircrafts in the British air space. Its operations are conducted centrally from West Drayton, and its engineers are reported to have stated that the strain on the central system grows inexorably, stretched to the limits during busy periods. A way to address these concerns is to scale up the system through decentralisation and maximal re-use of the existing legacy software. In this approach, the existing (central) system needs to be deployed as subsystems in many, geographically-apart centres; each subsystem will be responsible for a well-defined sub-domain of the over-all air-space and must frequently coordinate its activities with other subsystems so that certain services it provides are correct and consistent at the system level. The core requirement here is to have certain distributed services, which support such an expansion in a reliable and responsive manner. The services we identify here are generic enough to support a wide range of applications, say, from constructing global auction services over the Internet to managing replicated database servers on an institutional network. The focus of this paper is to highlight how such services can be constructed. We indicate the various models available and identify their strengths and weaknesses, thus exposing the design options available to a system builder. We expound on a particular model by presenting the features of the NewTop system that is designed in Newcastle and implemented in a CORBA compliant manner.


Publication metadata

Author(s): Ezhilchelvan PD

Publication type: Conference Proceedings (inc. Abstract)

Publication status: Published

Conference Name: Workshop on CORBA Based Real-Time Fault-Tolerant Systems for Industrial Applications (CORFIA 2001)

Year of Conference: 2001

Date deposited: 09/03/2011

Publisher: Centre for Development of Advanced Computing, Bangalore


Share