/ Introduction to Networking & Network Management
Engineering Science Department
Basics Lab Experiment, Part 2
Your Name: / Work Area & Computer: / Your Group:
You Partners: / Date:
  1. Objectives
  1. Setuptest connectivity between two computers.
  2. Observe the effect of cross-over & straight-through cables.
  3. Connect computer across a hub or a switch.
  4. Learn the effect of traffic congestion at the connecting device.
  1. Introduction
  1. In part 1 of the Basics Lab we learned how to configure the computer Ethernet port with an IP address so that the computer can be addressedaccessed by other computers.
  2. In this part 2, we desire to connect two computers together, exchange datamake a small LAN.

Note that computers are generally NOT connected directly togetherone may use a hub or a switch to connect two or more computers together.

  1. Procedure

Each group is expected to write one report for this experiment to be submitted by the end of the session or before the following Saturday for grading. Each of you, please participate in the experiment FULLY for yourown benefit.

For your report, you can save a copy of this instruction sheet in your flash memory or Ubuntu Document folder with file name “YourLastName_Basics_Part2.docx” & fill in the answers to the questions for submission.

Connecting Two Computers by Hub

  1. Boot your computers to Ubuntu. Now power on the Asante 2072 Hub at the Patch-Panel & let it warm up. Use a straight-through Ethernet cable (yellow, white, or blue) to connect the eth2 port of your computer to a port of the hubthe eth2 port of your partner’s computer to another port of the hub on the same row. Note that the Ethernet eth2 port at the back of each computer is already connected to the corresponding eth2 on the patch panel of your work area. Please make sure:
  • The eth2 port of your computers is activeconfigured with the correct IP address 192.168.0.x by pinging the eth2 of your computer with the same IP address. If the ping response does not show proper connectivity, follow the procedure in Basics Part1fix it.
  • The related lights of the ports on the hub should be green to indicate that the eth2 ports are active.
  1. Next, ping the eth2 of your partner’s computer by five pings to assure connectivity between the computersrespond to the questions below. If you had logical connectivity problem, follow step 1 above.

What is / Answer with units (-1%/incorrect answer)
Computer (A, B, C, D) you use
Computer (A, B, C, D) you pinged
The ping message you used
The default MTU (Max Transmission Unit) of the active interface
The minimum round-trip time (RTT) to receive a reply
The average RTT to receive a reply
The maximum RTT to receive a reply
The mean deviation of RTT
Number of packets Transmitted
Number of packets Received
% packet loss
Total time taken for transmission
RTT of the first packetthe unit
(3%) How does the RTT of the first packet compare with the other packets? Explain the difference.
  1. Repeat Step 2 by pinging your partner’s computer with 15 packets of size 20,000 octetspattern abcdefabcdef octets. At the same time, let your partner ping your computer with 15 packets of size 20,000 octetspattern abcdefabcdefoctets.

What is / Answer with units (-1%/incorrect answer)
The ping command you used
The minimum round-trip time (RTT) to receive a reply
The average RTT to receive a reply
The maximum RTT to receive a reply
The mean deviation of RTT
Number of packets Transmitted
Number of packets Received
% packet loss
Total time taken for transmission
The mean RTT herein step 2 compare
(2%) Explain your observations about the mean RTT, packet loss if any, esp. with respect to step 2.
  1. Repeat step 2 above using a packet size of 100,000 octets.

Question / Answer (-1%/incorrect answer)
Do you have any logical connectivity?
What is the message on the computer display?
Was the transmission successful? Explain.

Connecting Two Computers by a Switch

  1. Power on one of the Alcatel-Lucent switches OS6860 or OS645let it boot for a minute. Repeat step 2 above by moving the cables from the Asante Hub to the switchcheck that the related lights at the switch ports are ON.

What is / Answer with units (-1%/incorrect answer)
Computer (A, B, C, D) you use
Computer (A, B, C, D) you pinged
Is there proper connectivity between the two computers? If not, fix it.
The RTT of the first packet right after the successful ping
The minimum round-trip time (RTT) to receive a reply
The average RTT to receive a reply
The maximum RTT to receive a reply
The mean deviation of RTT
Number of packets Transmitted
Number of packets Received
% packet loss
Total time taken for transmission
The RTT of the first packet right after the successful ping
Compare the RTT of the first packet with the other packets
(3%)Is there any major difference between the average RTTs for hub & the switch?
  1. Repeat step 3with 15 packetsof size 20,000 octetspattern abcdefabcdefoctets with the two computersconnected through an Alcatel switch.

What is / Answer with units (-1%/incorrect answer)
The ping command you used
Is there proper connectivity to this port
The minimum round-trip time (RTT) to receive a reply
The average RTT to receive a reply
The maximum RTT to receive a reply
The mean deviation of RTT
Number of packets Transmitted
Number of packets Received
% packet loss
Time taken for transmission
(2%) How does the mean RTT herein step 3 compare?
(2%) Are there any advantages of using a switch over a hub?

Connecting Two Computers Directly By Cables

  1. Now connect the two computers directly (without the hub) via the eth2 ports on the patch panel by a straight-through Ethernet cable & repeat step 2above.

Question / Answer (-1%/incorrect answer)
What are the messages on the computer displays?
Are the computers connected logically?
Explain why the straight-through cable does or does not provide the proper connection.
  1. Connect the two computers directly (without the hub) via the panel by a cross-over cable & repeat step 2.

Question / Answer (-1%/incorrect answer)
What are the messages on the computer displays?
Are the computers connected logically?
(3%) Why does the cross-connect cable connect or not connect properly?
(3) What are the advantages of using a switch over a cable?
(3%) Which protocol carries the ping packet?
  1. Find out about the Asante Hub & Alcatel-Lucent switch & fill in the table. You may need to use the Internet.

Question (20%) / Asante 2072 Hub (ref 1) / Alcatel-Switch OS6450 / Alcatel-Switch OS6860
# of Ethernet ports
Ethernet port speed
# & type of console ports
Main capabilities
Configurability
Power consumption
  1. Please report any typos/mistakes, your comments & observations on this instruction sheet, lab, & equipment below.

2%,
  1. Report

1.Type in your name, group, station, & the computer at the top of the report & all your responses to the questions in the tables above including your observations & comments neatly & submit your report by the due date.

2.Please restart your PC so that it would be asleep in Windows for the automatic updates, but power off all other devices (-2% if not done).

3.Please remove the cables & return them to the cabinet, & clean up your station(-2% if not done).

Reference:

AMK10/7/20181