Deterministic Behavior

If a portlet generates events X and Y in that order, then events X and Y are delivered to the portlets in that same order. If portlet A and B are interested in Event X, either A or B can get event X first. If portlets A and B are interested in Event X, and upon receipt of that event, generate events Y and Z respectively. If portlet C is interested in Event Y and Z, then portlet C can receive events Y and Z in any order.