Purpose: To investigate the development of logistic chain of supplies from simple to maximal one, to consider informational flow evolution of logistic process till a single digital platform. To analyze the prerequisites for the transfer to a digital logistics and the level of development at the moment. To build the descriptive model of the interaction between a railway and sea transport. Methods: The research of the interaction between a station and a port is pursued in two major directions: information transfer, cargo traffic progression. The analysis of the development and classification of delivery chains is submitted. The descriptive models of document flow on import cargo traffic progression are built and analyzed. Results: The necessity of parallel development of transport and terminal complexes, RZD JCS infrastructure is pointed out for the transfer to network logistics stage. Information flow classification is presented. The descriptive model of the information interaction between a sea and port is built. Practical importance: The possibility to cut surplus document flow between a port and near-the-port station is shown, the need in such actions for the transfer to a single network platform is presented.