Event Channel buffering policy

As alarms, subscriptions, and other web services elements need to push data to a remote entity via the Event Channel, they are submitted for transmission to the Event Channel manager. Each submission includes the data to transmit and the buffering policy preferred by that specific message. This buffering policy is referenced by the channel manager, as it determines whether to immediately transmit a message or queue the message for transmission.

The buffering behavior for Event Channel messages when there is no Event Channel is configurable via web services on a per-event basis.

If there is no Event Channel present, and the policy is to discard, the message is dropped.
If there is no Event Channel present, and the policy is to queue, the message is added to the pending message queue (see note, below).
If there is an Event Channel, and the queue is empty, an attempt to transmit is made. If the transmit fails (for instance, the connection has recently been closed), the buffering policy is consulted.
If there is an Event Channel, but there are messages in the queue, the message is added to the queue.

Note In the initial implementation of web services, the queue only retains the 64 most recent submissions of any type.