GTS is the shape of traffic, and cars are the limit of speed. For example, the packet transmission rate of 600 /s per second is higher than 500. If it is gts, the higher 100 will be reserved for the next second when the interface is idle. If it is car, the higher 100 will be scrapped directly. The final flow chart of GTS is a complete wave line, and the peak value can be higher than cir. Car is an incomplete wavy line, and all the parts above cir are discarded.