How does bandwidth monitoring work?
Many routers (and other equipment) are equipped with counters. With a special network protocol you can read such a counter, wait for five minutes, and then read the counter again. In normal circumstances the counter will increase by a certain amount. Network bandwidth is usually measured per second. By dividing the five-minute increase by 300 (the number of seconds in five minutes) you’ll know the bandwidth. The monitoring software calculates the rate and displays it as an image. Real time measurement provides a historic view of the rate changing over time.
