Answer the following questions using the shell and traceroute,
ping, ifconfig and ethereal.
(Use ipconfig and tracert for windows NT. traceroute works
for some versions of windows.) Start menu, Run and type
either cmd or command to get to the DOS or command prompt.
It depends what Windows you are using (NT, 95, 98, ME, XP).
1. What is the IP number for the web server at Iowa State University?
Use the name www.iastate.edu to get there.
2. What is the actual name of the computer that is Iowa State'’ web
server?
3. How many hops are involved in getting from your computer
to the Iowa State web server?
4. What is the IP number of the web server at Dartmouth, which is
accessed by using www.dartmouth.edu?
5. What is the name of the web server computer at Dartmouth?
6. How many hops are involved in getting from your computer
to the University of Iowa web server at www.uiowa.edu?
7. Start up ethereal program, then type in the URL for one of your
favorite sites. Do not press Enter yet.
Start the Capture in Ethereal. Then switch back to the web browser,
and press Enter to go to your favorite URL.
Stop the Capture. Look at the captured packets and filter, if
necessary. Find out what the port numbers were for the HTTP
connection between your machine and the web server your request
went to. WHAT ARE THE TWO PORT NUMBERS, along with the corresponding
IP NUMBERS for the client and the server?
8. What is the hamming code word that gets sent out for the letter A
in ASCII. A = 65 = 01000001 in ASCII code.
Show the entire 12 bit Hamming codeword that got sent for the
letter A.
9. What binary digits actually got sent out by the sending computer,
if we assume that the Hamming codeword error detect protocol is
in use and the bits that were received were:
000010110111
1
12 0 8 6 4 2
11 9 7 5 3 1
000010110111
Note: An error did occur AFTER the data got sent, so it was
received correctly. Assume the error was only a one bit
error. Can you figure out what the ASCII character was
for the data that got sent.
Recall: A = 65, B = 66, C = 67, ... Z = 90
a = 97, b = 98, c = 99, ... z = 122