Source: Adapted from Montreuil, B. (2011). Toward a Physical Internet: meeting the global logistics sustainability grand challenge. Logistics Research, 3, 71-87.
The Physical Internet (PI) is a metaphor that aims at improving the connectivity and efficiency of logistics. It employs an analogy with the Internet, where information is distributed as packets moving through the network, mainly composed of servers and fiber optic cables. The PI relies on three fundamental concepts:
- Encapsulation. Goods are carried using various load units, with boxes, pallets, and containers being the most common. The purpose is to consolidate (assemble) load units into modular units labeled the PI containers. This implies that the load units can be scaled up or scaled down depending on the demand characteristics. The challenge remains to associate PI containers with the physical characteristics and capacity of the physical load units (e.g. truckload, container load).
- Interfaces. Focus on the capability to move PI containers across the transport chain. This can involve consolidating PI containers into loads allowing scale economies and their transport and relay (transshipment) across a multimodal network, including terminal facilities such as ports and distribution centers. These interfaces are also digital, with information systems able to interact by exchanging critical information.
- Protocols. In a logistical system, each layer involves a series of tasks that must be regulated by protocols, implying what is feasible considering the characteristics of the product, the demand, and the transport supply. Protocols are standard tasks (services) that can be performed through the physical and digital exchange between layers of the logistical system. For instance, the encapsulation of a PI container is bonded by the protocols of the physical characteristics of the products set by the Logistics layer (L7) and the shipment characteristics of the Shipping layer (L5).