The recent rise in maritime traffic volume, resulted from an increase in international marine trading volumes and the growing popularity of marine leisure activities, has increased the frequency of marine accidents. As human errors have accounted for the greatest percentage of marine accidents, a series of navigation assistance systems capable of assisting mates have been introduced. However, vessel data, which can be found in the previously proposed studies, are merely composed of a number of fixed sets of analyzed and assumed data, without mentioning any real-time data management techniques that can be embodied as real-time systems. In addition, as the proposed vessel data processing techniques are designed for Vessel Traffic Service Center, it is difficult to find data management techniques exclusively designed in consideration of the viewpoint of vessel operators. In this regard, a real-time vessel data management technique targeted at vessels operating at sea is to be introduced by this paper.