Community
Participate
Working Groups
In BPMN 2.0 spec there are multiple Pools specified. Between the Pools you can send messages forth and back. There is the distinction between White Box Pools (where your model is based) and Black Box Pools (e.g. Customer) that are not modeled out. Black Box Pool are needed to model the conversation between your Process and other involved parties like Customer, Supplier or whatever.
Tested with Google Chrome