Now that we’ve recognized that Communication is but a special kind of Activity, the model for Events comes into play. The model of events from Chapter 7 is updated in Figure 14-7. This time, however, it is a Communication that may be the cause of an (Internal) Event, which in turn, may be the cause of one or more Triggers that are the cause of other Communications.
On the other hand, a customer’s desire to place an order is an example of an External Event. It then may be the cause of one or more Triggers of an Activity Instance—specifically, a Communication that is the customer’s placing of a Telephone Call. This, in turn, will be the cause of one or more Triggers, each of which is of a particular Activity Instance, where an Activit