Question: A communication line is divided in two identical channels each of which will serve a packet traffic stream where all packets have equal transmission time T and equal interarrival time R > T. Consider, alternatively, statistical multiplexing of the two traffic streams by combining the two channels into a single channel with transmission time T /2 for each packet. Show that the average system time of a packet will be decreased from T to something between T /2 and 3T/4, while the variance of waiting time in queue will be increased from 0 to as much as T2/16.