STUDY OF ETHERNET BY SIMULATION

Abstract

A LAN is a combination of computer hardware, software, and communication cables within a single building that are linked to form an interconnected network of computers and peripheral equipment. It is an intelligent network confined to a moderate sized geographic area (10m-1Km) such as single office building, a ware-house or a campus which handles communication between devices, local storage, and external transmission of data. The interest in LAN s appear as it provides cost effective distributed processing environment, better reliability and dynamic restructuring of resources. The behaviour of a LAN can be predicted by simulation. The simulation is a effective tool for the optimum design phase and implementation of the network. Further investigation on trade-off among various network configurations and parameters can be carried on through simulation. One of the most widely known configuration of the LANs is the ETHERNET. It is multi-access, Packet-switched communication system for carrying digital data among locally distributed computing systems. The shared communication channel in an Ethernet is a passive broadcast medium with no central control. Coordination of access to the Ether for packet broadcasts is distributed among the contending transmitting stations using controlled statistical arbitrations. The behaviour of Ethernet can be analyzed by simulation. A scheme for the simulation of Ethernet LAN has been developed. It mainly consists of two modules: TRAFFIC GENERATION and PACKET TRANSMISSION. Traffic generation module generates traffic for the network with X as the mean packet arrival rate, and the packet lengths in the range of 72 to 1526 bytes. The mean packet arrival rate and the number of stations are the parameters to be changed for each simulation run. Packet transmission module takes care of a carrier sensing, collision detection and collision handling aspects. The module is initiated by values obtained from Traffic generation module. The program is written in Pascal.