[Q1] A File Transfer Application

New Concepts: scp command, bottleneck, VOQ length, packet loss
Review:
• XXX
Configuration File: cfg-queue-1nsp-loop.exp
Description:
This exercise covers traffic monitoring and a simple file transfer application scp 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 one command window to do this exercise. SSH into the host corresponding to $n1p2.
  REMINDER: You should SSH into the Ethernet interface, not the ATM one.
• In the $n1p2 window, make sure that you can send traffic to the n1p3 host by sending 10 ping packets to n1p3:

  		ping -c 10 n1p3
  	

  You should see messages that indicate 10 packets being sent at 1 second intervals, and the Traffic plot should indicate this traffic.
  Answer Question 1.
• In the $n1p2 window, copy a large file from n1p2 to n1p3. Run the following commands:

  		netstat -i
  	        scp /usr/bin/emacs n1p3:junk
  		netstat -i
  	

  Since the emacs executable file is about 4 Megabytes, the scp command will be transfering this file to the file named junk in your home directory on n1p3. Scp should report information of the transfer volume and speed. Answer Questions 2, and 3.
Questions:
1. Explain why the plots and ping report are consistent with each other.
2. Submit screen shots of the following windows:
   • traffic,
   • queue length, and
   • scp command.
   Explain in what ways the plots and scp report are consistent with each other.
3. Is the output of the nestat command consistent with the scp output? Explain.