Research on Workflow Model of Cooperation between 4PLs and 3PLs Based on Petri-net

The forth-party logistics (4PLs) was defined as the use of a consulting firm to integrate and manage a company's logistic resources and providers, including third-party logistics providers and other transportation companies. As the middlemen of logistics, 4PLs need to provide optimized logistic-solving schemes for customers. However, they must depend on 3PLs to carry out the solving schemes. Thus, 3PLs are not only the practical operators of 4PLs' schemes but also the undertakers of their logistics. Cooperation between 4PLs and 3PLs is a critical item that determines 4PLs' service levels. This paper firstly introduced the basic knowledge of Petri-net and then established a workflow model of cooperation between 4PLs and 3PLs based on Petri-net theory combining real application circum. Furthermore, this paper analyzed the basic characteristics of the established models through invariant analyzing method.