A four stage single-product supply chain (SC) consists of a retailer, a wholesaler, a distributor and a factory.
While the factory is a top SC node, which only receives orders from and ships the ordered items to its downstream node, all others also receive deliveries from and send orders to their upstream nodes.
Each SC node is modeled as an agent that reacts to
- the in-message event "receive order",
- the perception event "perceive reception of items" (delivery) and
- the time event "end of week",
and performs
- the out-message action "send order" and
- the action "ship items".