NASA ECHO Event Notification Service

Allows for the management of event notification subscriptions and delivery options. Event notification subscriptions allow third party applications to be notified by ECHO when an internal event occurs, such as a catalog modification (item added, removed, or updated) or an extended services modification (web service added, removed, or updated). The event notification framework supports the delivery of the notifications in various ways, including FTP push, email, and a web service callback. The event notification API is custom to ECHO, however it is inspired by other WS standards such as WS-Eventing and WS-Notification.