Study of overheads in packet-switched data networks

Abstract

An analytical formulation for determining the optimum packet size is presented. The mathematical model developed takes into consideration the message statistics, acknowledgment delays, channel-error characteristics, delays due to retransmission, packet header and the overheads due to blank padding of last packet etc. Network operational overheads have been considered to be functions of packet size. The system analysed is a half-duplex network operating in a stop-and-wait strategy for error detection and correction. The theoretical formulations lead to a 3rd-order algebraic equation having one and only one positive real root — which signifies the optimum packet size. Furthermore, these studies indicate that a packet size can be determined that minimises the network operational overheads; while the overheads due to blank padding increase more or less linearly with packet size.