Hello,

Clients can use Subscriptions and MonitoredItems to receive DataChangeNotifications whenever there is a change in the value of a monitored Attribute, such as the Value Attribute. This includes changes made to Values of Variable Nodes by other Client applications. However, DataChangeNotifications don’t specify why the Value has changed, so while other Clients would get notified of the changed, they wouldn’t know that the change was triggered by another Client. If letting the other Clients know that is crucial to your use case, you would need to have your Server generate an Event whenever a Client changes the Value of a Variable Node and use it to specify which Client changed the Value.

On the Server side, you can use classes that implement the IoManagerListener interface to detect when a Client is writing a value to a Node. See SampleConsoleServer and its MyIoManagerListener class for an example of implementing the IoManagerListener interface and using it.