1. A device for making centrally available, navigation parameter values of a vehicle, comprising components distributed in the following categories: a plurality of sensors that collect measurement data relating to at least one navigation parameter of the vehicle; a plurality of computers that process the measurement data collected by the plurality of sensors and calculate said navigation parameter values of the vehicle; a plurality of networks that link the sensors to the plurality of computers and link the plurality of computers to a plurality of user systems using said navigation parameter values; wherein: the plurality of networks transmit all the collected measurement data to the plurality of computers, and the plurality of computers calculate and make available, for use by the plurality of user systems, the value for each of the navigation parameter values as well as an estimated value of the fault associated with said navigation parameter values, using the transmitted measurement data and a single fusion algorithm contained in each of said plurality of computers.