Recent research shows that in financial terms the annual cost of this damage is between two and four billion francs. Increased public sensitivity can not doubt be explained by this sudden increase in the order of magnitude. The scale of the damage, the sensitivity of public opinion, the fact that measures which increase the safety of traffic may conflict with those intended to increase its efficiency are all factors which make it necessary to manage marine traffic in a way which ensures that marine space and the other resurces which are common to marine activities are shared as safely and as efficiently as possible. Several measures can be implemented to provide such management e.g. laying down and enforcing suitable regulations, providing navigators, in real time or off-line with relevant data which for whatever reason is not available on board. These measure are briefly described in the following.
Most marine activities are international in nature.
For this reason international organizations whose role is to lay down rules for the safety of marine traffic are extremely important. Planning of resources allocation to ships in Harbours. The first VTSs appeared in Europe in the 1950s. In view of the widespread use of radar on board vessels it seemed a natural development to use shore-based radar for maritime navigation surveillance. At that time radar was a new technique which made it possible under almost all weather conditions to acquire a previously unobtainable image of the traffic from the shore.