Towards an approach to sustain web services high-availability using communities of web services

Abstract

Purpose – In any critical system, high-availability of software components like web services has so far been achieved through replication. Three replication strategies known as active, passive, and hybrid, describe for example how many replicas are needed, where to locate replicas, and how replicas interact with the original web service and among themselves if needed. The purpose of this paper is to show how replicates could be substituted with components that are similarly functional to the component that needs back-up in case of failure. Design/methodology/approach – After examination of the different existing replication strategies, it was decided to test the suitability of the proposed web services high-availability approach based on communities for each strategy. To this end, the specification of web services using two behaviors, namely control and operational, was deemed appropriate. Findings – The active replication strategy is the only strategy that could support the development of a web services high-availability approach based on communities of web services. Practical implications – The proposed approach has been validated in practice by deploying a JXTA-based testbed. The experimental work has implemented the active replication strategy. Originality/value – Software component high-availability could be achieved by components that are similarly functional to this component, which permits the common limitations of existing replication strategies to be addressed.