Abstract: The information system concerning traffic in a road network (R) comprises a server (30) comprising: means (34) for obtaining at least one real duration (DEAB) of a run traveled by at least one vehicle (5) between two points (A, B) of the network, on the basis of information transmitted by a device (10) on board said vehicle (5); means (31) for statistically calculating, on the basis of said real durations (DRAB), an estimated duration (DEAB) for a run between two points (A, B) of the network; and means (34) for making the estimated duration (DEAB) available to at least one terminal (40, 10).