The main objectives of the MarCom project (‘Maritime Communications - broadband at sea’) are to investigate the main user needs and communication technologies requirements to accommodate those needs within the maritime community. The project will carry out several pilots to demonstrate the usability of terrestrial wireless technologies in combination with, and in some areas instead of satellite communication (SatCom). The major benefit to the maritime users are expected to be reduced costs, increased bandwidth, Quality-of-Service (QoS) and improved communication security and versatility. The MarCom approach is characterized by combining thorough investigations of present and future user needs through nine scenarios/user cases along with identification of cost-effective communication platforms to match the application requirements being obtained. The MarCom investigations have revealed the bandwidth needs for a set of application groups, and identified the data integrity requirements for each group. Furthermore this paper is addressing the MarCom work with the IMO/IALA e-Navigation strategic initiative in establishing the bandwidth requirements to obtain the major objectives of the e-Navigation concept.