The ratio of the highest value of a quantity to its average value, used as a measure to indicate the variability of the quantity. For example, in a computer network that connects a user’s workstation to a file server, the traffic is typically made up of long periods during which very little traffic flows, interspersed with periods of intense activity when the system transfers a large volume of data in a short time. A measurement of the average data rate over a period of many minutes may show a low apparent data rate, and give a misleading impression of the high data rate needed to provide satisfactory response to a request for a file movement or to refresh a user’s screen. The peak-to-average ratio indicates the extent to which the traffic consists of bursts of traffic.