Lab-Homework #7--I announced in class the Homeworks #6 & 7 are due on Dec. 11(Wed), 2002 but I realized that the due date is on the so-called "dead week" in which I should not assign any work to students. So, you do not need to hand them but these homeworks are interesting to carry out.

 

Multicasting(IGMP)

Read rfc for multicasting and answer the following:

The most current rfc for Multicasting is = ______________

224.0.0.1 means?= ____________________________________________

224.0.0.2 means?= ____________________________________________

 

An IGMP query is sent from a ____________ to a ____________.

How does a host respond when no processes in a group wish to continue membership? Select one answer from the following: ___

a) The host sends a report b) The host sends a query c) The host sends a NAK d) The host does not respond

 

Read the rfc called “Host Extensions for IP Multicasting” and find out:
The two new operations needed for the IP service to provide multicasting are:

1) _______________________________ 2)________________________________

 

Capturing Multicast packets

a) Download a program called ghsrv.exe from IBMLABPDC

Right click Network Neighborhood -> Find Computer .. -> Enter “IBMLABPDC” If this does not work, then enter "132.241.158.36" instead of "IBMLABPDC".

When found, open it. If login is needed use Username=csci  Password=csci.

Find the folder called Norton Ghost 6.0 and inside the folder find the program called ghstsrv.exe and download it to your desktop.

b) Set up Sniffer to capture all packets between Your station’s IP address & Your Default Gateway.

c) Run the ghstsrv.exe. Enter Your machine’s name(S101, S102, .. written on each machine) as the Session Name.

d) Find a ghost image file--Click Browse and find IBMLABPDC(or IBMLABSERVER1) and find a folder called Ghost Images. Inside the folder, find any file with .gho extension and click Open

e) In Sniffer, start capturing packets

f) In Ghost program click Accept Clients and wait about 3 minutes and Click Stop

g) In Sniffer, Stop and Display

Answer the following questions:

1) What is the IGMP Group address when your station(when you run Ghost Server program) reports a Multicast group membership? ____________________

2) What is the IGMP Group address when your station leaves the group(When you stop the Ghost Server program)? _____________________

 

Capturing packets for a telnet session

a) Set up Sniffer to capture all packets between Your station’s IP address & any Unix machine’s IP address(For example, Smallpox = 132.241.4.14---you can find this by “ping smallpox”)

b) Open telnet program from Start -> Programs -> Accessories -> telnet

c) Start capturing in Sniffer

d) In telnet program, enter your login name and when asked with password, enter a wrong password.

e) In Sniffer, Stop and Display and investigate the packets.

List at least two things you learned from this exercise.

1)_____________________________________________________________________

2)_____________________________________________________________________

Capturing packets for a http session

a) Set up Sniffer to capture all packets between Your station’s IP address & Any

b) Start capturing in Sniffer

c) Start Internet Explorer, wait until the browser completes the current connection

d) Stop and Display in Sniffer

e) Try to explain the captured packets--at least first 20 packets.