A data transmission system for transmitting data from a central station to a track-bound vehicle traveling on a track includes plural track-side transmitting and receiving devices communicating with an on-vehicle transmitting and receiving device. Each of the track-side transmitting and receiving devices is operatively connected to at least two control computers for communication with the central station. In this way, if the cases arises that the control computer of a pertaining track-side transmitting and receiving device crashes, the communication of this track-side transmitting and receiving device with the central station is maintained through intervention of the other one of the control computers.