Abstract: A network equipped with methods for detecting and notifying entities of changes in travel information (“events”) to users. In accordance with one aspect of the invention, a method for notifying entities of events comprises the steps allowing an entity to register interest in an event, and providing a means to notify entities when an event occurs, thus allowing a response to the notification. In accordance with another aspect of the invention, a system for notifying entities of events comprises a source system that tracks changes in travel schedules, a publish-and-subscribe technology that publishes events as they occur, and a receiving system that detects publication of events and that may also have the capability of notifying systems incapable of detecting publication that are interested in events.