[Q2] A Simple Pre-Configured Queueing Experiment

New Concepts: Iperf/UDP traffic generator, bottleneck, VOQ length, packet loss
Review:
• Tutorial => Filters, Queues and Bandwidth => Generating Traffic With Iperf.
• Iperf web site
Configuration File: cfg-queue-1nsp-loop.exp
Description:
This exercise covers traffic monitoring and UDP traffic generation using the iperf traffic generator and will begin to explore the idea of a bottleneck link.
Instructions:
• You must have a reservation for one cluster (no extra hosts) to do this experiment.
• Start the RLI, and open the cfg-queue-1nsp-loop.exp configuration file. You can get it here if you don't already have it.
• You will need atleast two command windows to do this exercise: one for the iperf server and one for the iperf client.
  • In one window, SSH into the host corresponding to $n1p2.
  • Repeat for $n1p3 in the other window.
  REMINDER: You should SSH into the Ethernet interface, not the ATM one.
• In the $n1p2 window, ping the n1p3 interface just to make sure that you have connectivity.
• In the $n1p3 window, start a UDP iperf server by running the following command:

  	          iperf -s -u
  	

• In the $n1p2 window, send UDP traffic for 10 seconds at 10 Mbps by running the UDP iperf client like this:

  	          iperf -c n1p3 -b 10m -t 10
  	

  Answer Question 1.
• Again in the $n1p2 window, send UDP traffic for 10 seconds but now at 400 Mbps:

  	          iperf -c n1p3 -b 400m -t 10
  	

  Answer Question 2.
Questions:
1. Explain why the plots and iperf reports are consistent with the 10 Mbps UDP traffic from n1p2 to n1p3.
2. Submit screen shots of the following windows:
   • traffic,
   • queue length,
   • perf client, and
   • perf server.
   Explain why the plots and iperf reports are consistent with the 400 Mbps UDP traffic from n1p2 to n1p3.