Exact analysis of delay performance of Go‐Back‐N ARQ scheme over multiple parallel channels

The Go-Back-N ARQ scheme, which is one of the typical error control methods for data transmission, has been widely used because of its good performance and easier implementation. Most analyses of the throughput and delay performances of the ARQ scheme (including the Go-Back-N) have been carried out for a single channel connecting a pair of a sender and a receiver. This paper gives an exact analysis of the delay performance of a Go-Back-N ARQ scheme, for a simultaneous transmission of multiple frames using multiple parallel channels between a pair of a sender and a receiver. In a discrete-time queueing model, the state of the system is described at each successful slot of frame transmission by using variables (which show the frame queue length and the existence of retransmitting frame) so that the distribution of the frame queue length is obtained from the solutions of the state equations. By using the results of the analysis, the distribution of the transmission delay of frames is obtained. The average delay characteristics are examined by using numerical examples. The results show that the delay performance can be improved by increasing the number of parallel channels. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(9): 27–41, 2001