Hyder Khoja
Page 1
3/6/2016
DCCT 3000
DATANETWORKS
LAB #8
ANALYZING FTP AND TELNET TRAFFIC
1.
CAPTURING TELNET TRAFFIC :
(a)
Set up Ethereal to capture your own packets. Write all the
steps necessary to do this.
_______________________________________________________
_______________________________________________________
_______________________________________________________
(b)
Telnet to hal, login and then stop the capture. Write every tep below.
__________________________________________________________
__________________________________________________________
__________________________________________________________
(c)
Click on TOOLS and then FOLLOW TCP STREAM. Answer the
following questions.
(1)
Do you see your user id and password ? _____________
(2)
Is it encrypted or plain text? _______________________
(3)
What are the client and Server Port #s ______________
(4)
Close the TCP Stream and try finding your user id password
on the screen.
Hyder Khoja
2.
Page 2
3/6/2016
CAPTURING FTP TRAFFIC :
(a)
Work in a group of 2 for this part of the Lab. Open Ethereal on your
computer and set it up to capture packets from your friend’s
computer
(b)
Let your friend ftp to an external site by typing following steps
ftp nic.funet.fi
login by using ANONYMOUS as user id and email as password
once logged in type ls –l , then type bye
(c)
On your computer, Click TOOLS and then Follow TCP STREAM
( d)
Now answer following Questions
(1)
Do you see your used id and password ?___________. What
format?________________________________________________
(2)
How many uses are currently logged in?________________
(3)
What are the client and Server port #s ?________________
(4)
What is the maximum number of users for this site
(5)
Close the TCP stream and find your user id and password in
the packets shown on the screen. Explain?
__________________________________________________________
__________________________________________________________
_________________________________________________________
3.
DNS RERQUESTAND REPLY :
(a)
Configure the Ethereal to capture your own packets.
(b)
Ping 192.75.71.100
(c)
Search through the captured packets. Do you see any DNS request
or Reply? Explain: _______________________________________
Hyder Khoja
Page 3
3/6/2016
(d)
Now Capture the packets using the command Ping hal.
(e)
Explain and discuss the difference between the two commands
______________________________________________________
_______________________________________________________
(f)
Type ipconfig /displaydns and press enter. Record the output and
study the results.
_________________________________________________________________
_________________________________________________________________
_________________________________________________________________
(g) How long these entries stay in the cache?
________________________________________________________________
________________________________________________________________
__
(h) Type ipconfig /flushdns and record the results.
________________________________________________________________
________________________________________________________________
_______________________________________________________________
(i)
Ping several hosts again and examine the DNS cache once more.
EXPLAIN?
________________________________________________________________
________________________________________________________________
________________________________________________________________
Hyder Khoja
Page 4
3/6/2016
LAB 9 RESULTS SHEET:
FTP:
FTP uses 2 port addresses on both the client and Server side: FTP control and FTP Data.
What are the 2 “well known” FTP port numbers for these ports
FTP CONTROL port # :__________________ FTP DATA port # : ___________________
How many packets does FTP use to send the user id: ________________________________
Telnet:
What is the Server side port number for Telnet: ____________________________________
Which protocol Telnet uses to login to a remote computer: ___________________________
How many packets does telnet use to send the user id and password: __________________
Does telnet suffer from the same security issues as the FTP. Explain their differences
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
FOR THE DNS QUERY PACKET :
The Source Port Number: ____________________________
The Destination port number: __________________________
In what Header did you find these port numbers:_________________________What is the protocol code for UDP: ____________________________________
What is the Length of the UDP datagram: _______________________________
What is the length of the UDP Datagram Header: _________________________
For the Host , the type _________ and Class______________________
Hyder Khoja
Page 5
FOR THE DNS RESPONSE PACKET:
The Source Port Number: ________________________________________________
The Destination Port number: ____________________________________________
The Length of the IP Datagram Header: ___________________________________
The Length of the IP Datagram: __________________________________________
In the UDP datagram, list the 6 elements found in the ANSWERS entry.
3/6/2016