Punktförmige Zugbeeinflussung
After acknowledging the warning signal the train has to stay below the braking curve (German "Bremskurve") - fast trains may travel up to 165 km/h and they must reduce the speed to below 85 km/h after 23 seconds. Note that the operation of high speed trains beyond 165 km/h is not based on visual wayside signals or PZB inductors (using LZB or European Train Control System cab-signalling instead in Germany).
Passenger rail terminology
A number of both technological and practical variables begin to influence trains in the vicinity of 500–600 km/h. Technologically, the limitations are by no means beyond reach, however conventional trains begin to encounter several physical obstacles, most notably track damage and pantograph limitations. It is important to note that the current world record for rail vehicles is held by the TGV V150 set on 15 April 2007 at , and conventional trains may indeed eventually reach into ultra high-speeds. However, this test has shown that speeds over 500 km/h are unrealistic for regular usage; it wears down the material too much. Based on current and foreseeable technology, these speeds will more than likely be reached predominantly by maglev trains. The two most prominent maglev trains are the Transrapid with a maximum speed of and the Japanese MLX01, which holds the world land speed record for rail vehicles at .