Suppose users share a 2 Mbps link. Also s uppose each user transmits contin- uously at 1 Mbps when transmitting, but each user transmit s only 20 percent of the time. suppose packet switching is u sed, f ind the probability that a given u ser i s transmitting. Why will there be essentially no queuing delay before the link if two or fewer users transmit at the same time? W h y will there be a queuing delay if three u se r s transmit at the same time? Suppose now there are three u sers. Find the probability that at any given time, all three users are transmitting simultaneously. Find the fraction of time during which the queue grows.