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Douglas E. Comer


Computer Science Department
Purdue University
West Lafayette, IN 47907

webmaster: W. David Laverell


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Hands-On Networking: Experiment 3.3 Home > Student > Experiments > 3.3

Experiment 3.3

Chapter 3
3.1 3.2 3.3 3.4 3.5

Here is what you should see on a Unix machine:
Script started on Tue 14 Jun 2005 11:25:15 AM EDT
stallman ~$ telnet ursa.calvin.edu 25
Trying 153.106.4.1...
Connected to ursa.calvin.edu.
Escape character is '^]'.
220 ursa.calvin.edu ESMTP Sendmail 8.12.10/8.12.10/SuSE Linux 0.7; Tue, 14 Jun 2005 11:25:27 -0400
HELO calvin.edu
250 ursa.calvin.edu Hello [153.106.117.88], pleased to meet you
MAIL FROM: nosuchperson@calvin.edu
250 2.1.0 nosuchperson@calvin.edu... Sender ok
RCPT TO: lave@calvin.edu
250 2.1.5 lave@calvin.edu... Recipient ok
DATA
354 Enter mail, end with "." on a line by itself
What would we do without you?
.
250 2.0.0 j5EFPRcm002797 Message accepted for delivery
QUIT
221 2.0.0 ursa.calvin.edu closing connection
Connection closed by foreign host.
stallman ~$ exit
exit

Script done on Tue 14 Jun 2005 11:27:32 AM EDT

Again things are not so simple with windows. The behaviour is similar to that encountered with Experiment 3.2, you cannot see what you are typing unless you follow the following procedure kindly provided by Petar Konovski of Birkbeck, University:

  1. telnet

  2. set localecho

  3. follow the directions in Experiment 3.3 typing very carefully.

  4. Hit the Enter key.

  5. Type "Quit".

You need to be very careful about sending fake email. Under the right circumstances it can be funny, but you are taking a big risk. I have pretty much stopped doing it completely. Tell your friends about this capability so that they know that even email that seems to be from someone they know may be fake.



This site is maintained by W. David Laverell of the Computer Science Department at Calvin College. For assistance or corrections, please contact him at lave@calvin.edu.