Publish-subscribe services for urgent and emergency response

In urgent and emergency response situations, publish-subscribe services need to go beyond information dissemination to facilitate response collection, and even collaboration, among the recipients. We introduce flexible delivery, role-based subscription guidance, and historical event matching to address the requirements of urgent response applications. Flexible delivery allows publishers to choose the most appropriate communication technique for the urgent situation. Role-based guidance provides an interface for subscribing to events from the user's perspective. Historical event matching allows subscribers to join ongoing collaborations for events that occurred in the past. Together theses techniques allow the creation and support of ad hoc communities of interest to address urgent situations. We report our experience with these techniques during 3 years of production use for escalating product repair issues for our company. Forum provides the first production use cases that require historical matching of persistent events in publish-subscribe services.