In certain cases, a PT traffic stream should be held back slightly so that, for example, a train arriving at a stop uses the same stage as the train leaving the stop. In this case, the train leaving the stop would be held back depending on the train arriving. The hold back parameter is used to determine whether a traffic stream is to be held back. On the other hand, the maximum permitted time difference to the "expected arrival seconds" of the two PT traffic streams (e.g. train at the stop to friendly oncoming train from the line) is determined. The decisive traffic stream is the one that can cause a delay (e.g. train on free route). The dependent traffic stream is then the one that is held back (e.g. train at a stop).