100-150 units choose 20 megabytes of fiber optic, you can limit the speed (speed limit when there are many people, not limited when there are fewer people) due to cost considerations, the general bandwidth is not enough, so the key is that you limit the speed to do a good job of limiting downloads, restricting a variety of applications that account for too much traffic, and to ensure that the most commonly used applications of the bandwidth is the right solution.