Chipp Jansen - chipp [at] sci.brooklyn.cuny.edu

INSTRUCTIONS

This lab shows you some tools on the computers in the lab and some (hopefully!) interesting things on the Internet. The questions asked are intended to give you things to think about. You do not have to send me your answers to those questions. HOWEVER, YOU DO NEED TO SEND ME E-MAILS, as instructed in PART I.

A HOMEWORK assignment will be posted shortly on the class web page that requires you to use the skills and tools you learn or review below, so BE SURE TO ASK IN THE LAB IF YOU NEED HELP WITH ANY STEPS!!!!

In this part, we start with a basic introduction to the tools that we will be using this semester for the Internet-based assignments. We review the basics of working with Microsoft Windows, using a simple text editor and how to use the mouse to move text around.

1. Web browsing
   1. Use Firefox to go to the course home page: http://www.sci.brooklyn.cuny.edu/~chipp/cc3.12/.
   2. Now open Internet Explorer and look at the same page. Note any differences in the way the page is displayed.
   3. Click on the syllabus link and find the link called A.2 internet lab. There you will see an on-line copy of this lab (which will help you with the next section...)

2. Cut and Paste

   The location of the course web page is http://www.sci.brooklyn.cuny.edu/~chipp/cc3.12/ But the location is rather long, so rather than type it manually, we will use the mouse to copy text:

   • Position the mouse on the left side of the "http://..."
   • Hold down the left button on the mouse.
   • With the left button in a down position, sweep the cursor over the whole line from left to right. You should see the line become highlighted as you move the mouse over it.
   • When you reach the end of the line, let go of the left mouse button and press <CTRL>-C (Control and C buttons at the same time)
   • Open a new TextEdit window.
   • Position the cursor in the TextEdit window and press <CTRL>-V. A copy of the location of the course Web page should appear.
   • Now try to do the same thing in the Web browser. Now click in the field (white area) near the top of the window that is used for typing in the location of a Web page and use <CTRL>-V to paste in the location of the CC 3.12 web site.

3. Email (part I)
   1. If you don't have email, go to http://mail.yahoo.com and set up an email id.
   2. Read your incoming mail. By now you should have an email confirmation of your subscription to mailing list.

4. AIM
   1. If you don't have an AIM (AOL Instant Messenger) screen name, go to http://www.aim.com and set up a screen name (click on Don't have a screen name? Get one FREE).

   2. My screen name is chippbot.
      Try to send me a message!

5. Email (part II)
   1. Send me a short email message. My email address is:
      chipp@sci.brooklyn.cuny.edu
      Your message can just say "hello prof jansen". I will reply to you.

6. Email (part III)
   1. Create a file in TextEdit and put the following information in it:
      • Your full name, your email address and your AIM screen name
      • Your declared (or anticipated) major and class standing (e.g., Freshman, Sophomore, etc.)
      • What computers and operating systems do you have experience with (e.g., PC running windows 95, or Mac running OS-X)?
      • How would you characterize yourself when it comes to computers (e.g., confident, comfortable, clueless, I can manage, etc.)?
      • Have you used computers in a BC lab before?
      • List the software you have used before this class (e.g., web browsers, email, microsoft word, excel, powerpoint, etc.)
      • Have you ever done any computer programming? If yes, using what languages and what for?
      • What do you think you will use computers for after this class is over? After college?
      Save the file on the desktop.
   2. Now email me the file as an attachment (in your mail window, find the paper clip icon).
   3. CC yourself on the message, so you will have a copy of the file too.
   4. When you are done, Delete the file from the Desktop by dragging it to the Recycle bin. To make sure the file is really gone, empty the recycle bin.

1. URLs, IP addresses, DNS names, tracert
   For this part, you will use utilities at the web site http://www.dnsstuff.com When you go to that site, you will see a number of places to type in web addresses and buttons to click on.

   1. First, go to the section marked DNS lookup.
      Type www.google.com in the box and click on Lookup. (Leave A selected in the drop-down list).
      What do you see? Can you find the numeric IP address of www.google.com?

   2. Second, go to the section marked Ping. Ping is a handy network utility that will test if a host is alive. It will also give you statistics about how long it takes to send a message to a host.
      Type www.google.com in the box and click on Ping.
      How long does it take to get a reply from google?

   3. Third, go to the section marked Traceroute. Traceroute is a handy network utility that will show you the route that messages take to get from you to a host.
      Type www.google.com in the box and click on Traceroute.
      How many "hops" does the message take?

   4. What happens if you type in a DNS name incorrectly? In your web browser, try going to
      http://www.brooklyn.cuny.e or http://www.brklyn.cuny.edu
      Try to ping them in dnsstuff.

   5. What happens if you type in an IP address directly, instead of a DNS name? In your web browser, try going to
      http://146.96.128.102
      Try looking up that IP address in DNS Lookup. What information can you find there?

   6. What if you type the IP address in incorrectly? In your web browser, try going to
      http://146.245.100.2.
      Try pinging 146.245.100.2

2. Exploring your IP Address
   The computer that you use (when connected to the internet) has its own IP address. When you browse to web-sites on the internet, the web-site can tell certain things about your IP address, general location, and information about your web-browser
   
   1. Go to: http://whatismyip.com/
      What is your IP Address? Write it up in the front on the board (gives you a chance to stretch your legs).
   2. Go to: http://www.google.com, search for: what is my ip.
      Look at the first hit. You will find the site "WhatIsMyIP.com" you just previously visited. What is the IP Address listed next to it? Is it the same as yours? You can do a Reverse DNS Lookup at dnsstuff to find out the company that owns that IP Address. Are you surprised with the results?
   3. Go to: http://www.showmyip.com/geo/
      There is alot of information on this page (and advertisements!). This site resolves your IP address to a Geographical Location. How specific are they? Scroll down to the table, what kind of web-browser does it say you are using?
      
      
      
3. Visualizing the Internet
   
   1. Go to: http://www.mappingcyberspace.com/gallery/figure5_4.html
      Map B shows the number of domain names in New York City. The larger the bars, the more domain names there are in a region. Approximately which section of NYC has the most domain names?

   2. Go to http://www.mappingcyberspace.com/gallery/
      What are some of the other types of graphics available? Can you find the drawings of the early internet (ARPANET) topology from 1969 and 1977?

4. Participatory Web
   

1. Go to: http://images.google.com/imagelabeler/
   This is one of a growing number of applications on the web that take advantage of the large number of internet users to solve problems collectively. Play a round of image labeling. How do you think the imagelabeler works?
   
   
   
2. Go to: http://recaptcha.net/
   Similar to the imagelabeler where it uses the large number of internet users to solve the problem of book digitization. What is a CAPTCHA, and why are they used? (hint: this was something already being done on web-sites) What is reCAPTCHA, and how do they know that the human digitizing the word is giving a good answer?
   
   
   
1. Command Line
   
   Terminal is a program that allows you to access the computer you are using through the command line. The command line is a text-based environment in which you type a command, press enter, and then view the resulting output.
2. 1. Find the Terminal program on your computer. (Use Spotlight - the blue magnifying glass in the top right-hand corner of your screen)
      
      
   2. Run Terminal - you will see a text window appear. The cursor is preceded by a few words followed by a '$'. This is called the command prompt. The Mac you are using is actually based on an UNIX Operating System! Using the command prompt allows you to interact with the OS in a text-based manner. Let's run the same network utilities that we did before, but from the command line...
      
      
      1. Type nslookup google.com and then press the return key. What do you see? Is this output familiar something that you've seen before?
         
         
      2. Type traceroute google.com and then press the return key. How many hops does it take?
         
         
      3. Type ping google.com and then press the return key. What is the response time?
         
         
      4. Copy the text in the Terminal window and Paste it into an e-mail it to me ( chipp@sci.brooklyn.cuny.edu ).