We are subscribing for events on Event Server. For "camera going offline", we are using Communication Loss event. Is there an event for "Camera coming online"?

Please explore the Status Viewer sample.

I would say that in this sample the “responding” and “not responding” events are the two to follow.

I see both Protocol Integration and Event Server in the tags, and that seems strange, I think there is a very real possibility that you are doing something very different and my answer does not fit. If the answer does fit please elaborate on what you do.