Method for delivering road traffic data to at least a first position enabled user terminal of a plurality of position enabled user terminals, each of said position enabled user terminal being embarked on board a vehicle moving within a road infrastructure, said user terminal being connected through a telecommunication network to a road traffic management server, said method comprising the acts of: ▪ receiving at the road traffic management server positions and speed data from the plurality of position enabled user terminals, ▪ estimating road traffic data at a plurality of predefined checkpoints belonging to a mesh of predefined checkpoints matching the road infrastructure using the received positions and speed data; ▪ producing an estimated road traffic map by associating each predefined checkpoint with its estimated road traffic data; ▪ transmitting at least one portion of the estimated road traffic map to the first position enabled user terminal for subsequent display of said portion; and wherein the said act of estimating road traffic data at a particular checkpoint of the said mesh of checkpoints comprises the acts of : ▪ grouping all the speed data corresponding to data positions that have been sent by the said enabled user terminals and which are located at a distance less than a predefined threshold distance from the said particular checkpoint; ▪ calculating using all the said speed data that have been grouped, at least one instantaneous road traffic data specific to the said particular checkpoint, for subsequent association to the said particular checkpoint; wherein it comprises a preliminary act for dynamically building (INIT) the said mesh of checkpoints comprising the following steps of: ▪ if there is no checkpoint in a minimum predefined distances around an instantaneous position enabled user terminal of a plurality of enabled user terminals, a new checkpoint is created to complete the said mesh of checkpoints with geographical coordinates corresponding to the said position of the said enabled user terminal; ▪ matching the created checkpoint to the road infrastructure. ▪ receiving at the road traffic management server positions and speed data from the plurality of position enabled user terminals, ▪ estimating road traffic data at a plurality of predefined checkpoints belonging to a mesh of predefined checkpoints matching the road infrastructure using the received positions and speed data; ▪ producing an estimated road traffic map by associating each predefined checkpoint with its estimated road traffic data; ▪ transmitting at least one portion of the estimated road traffic map to the first position enabled user terminal for subsequent display of said portion; and ▪ grouping all the speed data corresponding to data positions that have been sent by the said enabled user terminals and which are located at a distance less than a predefined threshold distance from the said particular checkpoint; ▪ calculating using all the said speed data that have been grouped, at least one instantaneous road traffic data specific to the said particular checkpoint, for subsequent association to the said particular checkpoint; ▪ if there is no checkpoint in a minimum predefined distances around an instantaneous position enabled user terminal of a plurality of enabled user terminals, a new checkpoint is created to complete the said mesh of checkpoints with geographical coordinates corresponding to the said position of the said enabled user terminal; ▪ matching the created checkpoint to the road infrastructure. <EOS>