Performance evaluation of a buffer-based CSMA/CD protocol for single channel optical Ethernet LAN

Abstract

Using CSMA/CD, Ethernet suffers capture effect that makes it unsuitable for supporting real-time multimedia traffic. It does not guarantee delay bound and behaves poorly under heavy load conditions, leading to excessive delay, throughput degradation and packet loss because of excessive collisions. Aim of this paper is to increase throughput and reduce average packet transfer delay of CSMA/CD-based LAN by reducing collisions and eliminating packet loss. Here, each user has a finite buffer capacity that helps to reduce collisions and Ethernet capture effect. At the same time, to eliminate packet loss, a new special-jamming signal is used. The network performance in terms of throughput, average packet transfer delay and percentage of collision based on the proposed protocol shows significant improvements. Throughput is increased more than 10% whereas average packet transfer delay and percentage of collision are reduced to less than 1.5 ms and 3%, respectively, compared to conventional protocol.