[This is preliminary documentation and subject to change.]
Web-Based Enterprise Management (WBEM) events are occurrences that either correspond to conditions that arise in the real world or to changes in repository managed by the Common Information Model Object Manager (CIMOM). After an event, a notification of its occurrence is generated by an event provider and delivered by CIMOM to one or more registered recipients, known as event consumers. Event providers send notifications in response to event occurrences, regardless of whether or not there are registered consumers. Event consumers register to receive notifications without knowledge of how and by whom events and their corresponding notifications are provided. Consumers register to receive notifications by specifying a filter. The filter is created using the WBEM Query Language (WQL). It describes the conditions under which the consumer wants to receive notification.
CIMOM serves as the intermediary between consumers and providers. Providers route notifications to appropriate consumers through CIMOM. Consumers registering for an event send their registration to CIMOM where it is held until it is cancelled or, in some cases, the consumer terminates. Providers generating a notification for an event also send their notification to CIMOM. By matching notifications with registered consumers and discarding those notifications that do not pass through the filter. The location of the consumer is not a factor; CIMOM forwards notifications to both local and remote consumers.