What AE-N-A Is
AE-N-A (Alarm and Event-Notification-A) is the BACnet Interoperability Building Block (BIBB) for the client side of event notification: a device that appears in a Notification Class Recipient_List and receives ConfirmedEventNotification or UnconfirmedEventNotification when an AE-N-I-B or AE-N-E-B device originates one.
Where AE-N-I-B and AE-N-E-B are the alarming controller’s BIBBs, AE-N-A is the operator workstation’s, or any monitoring device’s. A device claiming it does not evaluate the algorithm; it receives the result and, if the notification arrived confirmed, acknowledges receipt at the service layer. It also receives the follow-up notification a device sends after an operator acknowledges an alarm, which is how a second workstation learns someone already handled it.
What It Requires
A device claiming AE-N-A implements the receiving side of both notification services and does something useful with what arrives: display it, log it, forward it, or hold it pending operator action. The BIBB says nothing about acknowledgment of the alarm itself; that is AE-ACK-A, a separate claim for initiating AcknowledgeAlarm.
| Service received | What it carries |
|---|---|
| ConfirmedEventNotification | A notification the sender expects a service-layer acknowledgment for; the recipient’s stack answers automatically |
| UnconfirmedEventNotification | Fire-and-forget; no service-layer acknowledgment at all |
Whether a given notification arrives confirmed or unconfirmed is set on the Notification Class’s recipient entry, not decided by the receiving device.
Where You Meet It in the Field
Every BAS front-end, alarm-management server, and mobile alerting gateway is claiming AE-N-A. It is also the BIBB a testing tool needs to verify a device actually dispatches what it claims to, since proving BUFFER_READY works means being a device that can receive it.
[!NOTE] Receiving a notification and acknowledging an alarm are different acts on different services. See AcknowledgeAlarm and the operator workflow for the second half.
What Chipkin Provides
The CAS BACnet Stack supports AE-N-A today: receiving confirmed and unconfirmed event notifications and answering the service-layer acknowledgment a confirmed one requires. It is the mechanism the CAS BACnet Explorer uses to show alarms as they arrive, which makes it the fastest way to confirm a device you are building actually notifies the way its PICS claims.