";
print "";
print "
";
print "";
print "You are at IP Address $ENV{'REMOTE_ADDR'}
";
print "Which resolves to $ENV{'REMOTE_HOST'}
";
print "It is now $ADATE
";
if ($ENV{'REMOTE_USER'} gt " ")
{
print "You are really ";
print "$ENV{'REMOTE_USER'}
";
}
else
{
print "Rats. Your server will not reveal your true identity.
";
}
print "You enjoy surfing with ","$ENV{'HTTP_USER_AGENT'}
";
print "
";
print "";
print "Hmmm. If I were an evil hacker or if you were ";
print "doing something ";
print "really bad and I had a warrant, I guess going by your ISP's address, ";
print "your IP number, the time, and the billing information- I could ";
print "get your home address and phone number. If you have your own ";
print "static (permanent IP address) it would make my job easier!";
print "";
print "Hmmm. If I were a spammer. ";
print "I am NOT either doing it or showing you how, but if ";
print "you are using Netscape or MSIE with your mail enabled- I could ";
print "with a small JAVA applet- have your e-mail address in my ";
print "mailbox right now!";
print " ";
print "Hmmm. If I were a marketer what would this ";
print "small amount of information tell me?";
print " ";
print "- I know by comparing your domain to a geographic list ";
print "of servers- where you live!";
print "
";
print " - Does your domain end with edu? If so I know you ";
print "are associated with that school. Same thing for com, ";
print "unless it is an ISP. I also can tell where mil, gov, and ";
print "org people are from. You might also be from another country";
print "
";
print " - I can tell what browser you are using.";
print "
";
print " - From looking at the version, I can tell if you have the ";
print "latest version. Most serious net users do.";
print "
";
print " - I know what operating system you are using.";
print "
";
print " - Maybe I can get an idea of when you are on-line";
print "
";
print "In fact, taken as a whole, a webmaster can get a very good ";
print "idea who his or her audience is. For instance. If I notice ";
print "that most of my hits are from people using MSIE, I may want ";
print "want to change that little my site looks best with ";
print "message. ";
print "";
print "All of this information is actually captured in the various ";
print "server logs. By collecting this information in my CGI script, ";
print "such as a survey, I do not have to try and figure out which ";
print "hit it was- an impossible task!";
print " ";
print "So when you do a CGI script, keep in mind that you might try ";
print "logging accesses. This will be a topic for another day. ";
print "Next time you complete any type of HTML/CGI form and hit ";
print "SUBMIT- remember what you are really telling that server!";
print "
";
print "";
print "The Cast of Characters";
print "";
print "Here are the environmental variables that I used:";
print "";
print "- REMOTE_ADDR: The numerical IP address you are at";
print "
- REMOTE_HOST: The host you are logged on to";
print "
- REMOTE_USER: If your server wants to tell me- your real user name";
print "
- HTTP_USER_AGENT: The brand and version browser you are using";
print "
";
print "
";
print "";
print "";
print "Click here to download a copy of this program!";
print "
";
print "";
print " |
";
print "