A CLOUD-BASED XML PUBLISH/SUBSCRIBE SERVICE

XML message filtering and routing have been recognized as a standard for data exchange for XML dissemination services. These services are often realized using the Publish/Subscribe (pub/sub) model which is commonly used for various web-based systems. The conventional XML filtering and forwarding technique is an application-layer multicast approach that relies on XML-capable brokers that are built above the network layer for message dissemination. Such an overlay model introduces a great deal of overhead in terms of initial deployment and subsequent operational cost for those XML-capable brokers that are typically supported by geographically distributed Internet Service Providers (ISPs). This paper proposes an approach to the deployment of the XML pub/sub systems over the cloud without the need of any special arrangements of physical brokers across the networks or ISPs). In addition, changes to the software deployed in the cloud can be made directly and easily by the XML pub/sub service provider. The paper describes experiments that use both Amazon and Google clouds for rapid XML pub/sub deployment. In addition, the paper presents a performance comparison between the conventional XML multicast model and the cross-layer model deployed over the cloud.