Visualization, Vulnerability and Manipulation in Internal Communications Systems on the Navigation Bridges

This paper is the continuation of a project previously presented for the training of students in both the Bachelor's and Master's degrees in Radio Engineering. The proposal makes it possible to visualise and understand how navigation equipment shares information on board a ship, using low-cost devices. Through an SDR receiver, free software (SDA, ShipPlotter, OpenCPN) and minimal investment, students can receive AIS transmissions, decode them, get their NMEA frames to view over electronic letters. This practice recreates an ECDIS environment in a PC, promoting self-learning, technical curiosity and innovation. In addition, it explores the possibility of generating false NMEA frames to demonstrate the vulnerability of the system, reinforcing the importance of information integrity in navigation. The project demonstrates how, without costly equipment, it is possible to assimilate complex concepts into communication and navigation systems, reinforcing the motivation and active learning of students.