Internet Traffic Trends Toward Poisson and Independent as the Load Increases

Network devices put packets on an Internet link, and multiplex, or superpose, the packets from different active connections. Extensive empirical and theoretical studies of packet traffic variables -- arrivals, sizes, and packet counts -- demonstrate that the number of active connections has a dramatic effect on traffic characteristics. At low connection loads on an uncongested link -- that is, with little or no queueing on the link-input router -- the traffic variables are long-range dependent, creating burstiness: large variation in the traffic bit rate. As the load increases, the laws of superposition of marked point processes push the arrivals toward Poisson, the sizes toward independence, and reduces the variability of the counts relative to the mean. This begins a reduction in the burstiness; in network parlance, there are multiplexing gains.