This project is designed to demonstrate the operation of the Ethernet network. The simulation
in this lab will help you examine the performance of the Ethernet network under different
The Ethernet is a working example of the more general carrier sense multiple access with
collision detect (CSMA/CD) local area network technology. The Ethernet is a multiple-access
network, meaning that a set of nodes sends and receives frames over a shared link. The
“carrier sense” in CSMA/CD means that all the nodes can distinguish between an idle and a
busy link. The “collision detect” means that a node listens as it transmits and can, therefore,
detect when a frame it is transmitting has interfered (collided) with a frame transmitted by
another node. The Ethernet is said to be a 1-persistent protocol because an adaptor transmits
its ready frame with probability 1 whenever a busy line goes idle.
In this lab, you will set up an Ethernet with 30 nodes connected through a coaxial link in a
bus topology. The coaxial link is operating at a data rate of 10 Mbps. You will study how the
throughput of the network is affected by the network load as well as the size of the packets.