BACnet clients can read objects by making ReadProperty requests, where the client requests data from Security Center, or by Change of Value subscriptions, where Security Center actively sends change notifications to subscribed clients.
The supported Change of Value related services are:
- ConfirmedCOVNotification
- UnconfirmedCOVNotification
- SubscribeCOV
- SubscribeCovProperty
For more information on change of value subscriptions, see the documentation that came with your BACnet client.