Performance evaluation of Digital Communication Network"

Abstract

In many of the standard protocols in computer communication, the acknowledgment is sent with the data. So there is a problem in the case of asymmetric traffic, i.e. when the traffic in one direction is less or more than the traffic in the other direction. Obvious solution of this case is to send the acknowledgment alone after certain time T. This method has two disadvantages. The first is that the time interval T leads to a delay in the transmission. The second is that the acknowledgment needs a full header, thus the utilization of the network decreases. In our new method, we don't send one acknowledgment to every received packet consistently. Acknowledgment transmission depends on the traffic ratio of the two hosts. The method is to send one acknowledgment to one received packet when the traffic ratio is around one. One acknowledgment is sent for two packets when the traffic ratio is around two, and so on.

Emphasis is done to find the limits at which switching is achieved and to find the increase in network utilization and the decrease in packet delay which yield the advantages of this method.

A thorough simulation of network performance under this technique with different two way traffic distribution was carried out. Results are illustrated and due comments conclude the thesis. It is shown that high network performance and low packet delay are obtained in the case of asymmetric traffic.