CMSY129 Principles of the
Internet
Week #4 - Internet Utilities and Hypermedia
January 19 - January 25, 2002
It's easy to get the idea that the internet is World Wide Web pages – it's a large and very visual medium to use to share information with the world. The original internet was entirely text-based, though – although you could also download some graphics files. Not many people even bother with some of the plain text protocols any more – they've been replaced largely with www sites (everyone wants the graphics).
It's easy to think of the internet as just world wide web pages. In this unit, we'll explore the slimy underbelly of the internet – the other things on the internet for you to use besides the web.
A quick look "behind the scenes" of any web page can be found by viewing the source code. From Netscape or Internet Explorer, if you go to View | Page Source, you can view the HTML code that makes up almost any page on the internet. You can then save this file if you want to, dissect it, modify it, change the contents to your own information with the original layout, and save it as a new file. This is one of the ways people learn how to make their own web pages – by looking under the hood of someone else's site.
Gopher
Before graphical interfaces like Netscape, all the information on the web was in text format, and was shared between computers using a protocol called Gopher. It was originally developed at the University of Minnesota as a way for each campus and organization to share information over the university's computer network. The University of Minnesota's mascot is the gopher, but it was also a convenient name for a system that let you "go fer" information online.
Gopher is a menu-driven system. Gopher servers arrange their contents in hierarchical menus in plain language. You explore a Gopher server by selecting menu items which in turn can lead to other menus, files, images, sounds, search tools, ftp sites, or telnet resources.
Each item on a Gopher menu is actually a set of instructions that tells the Gopher server what to do when someone selects them. Unlike the http: format, though, gopherspace documents don't have embedded hyperlinks - you don't click and surf to another site. You can only "drill down" or up further within a "gopher hole" of information.
You can connect to a Gopher site using Netscape by clicking on a hypertext link to a Gopher site, or by typing the gopher URL in the Location line. Instead of beginning with http://, the URL will begin with gopher://
If you use Gopher, you'll end up seeing references to Archie, Jughead, and Veronica. It's not a comic book - they're special search utilities for Gopher and FTP. Read more about them by clicking here.
Some gopher sites:
(check out the URL when you go to these sites and you'll notice that instead of
starting with http:// they start with gopher://:)
Gallaudet
University
Library of Congress
Telnet
Telnet (short for Telephone network) is a way to access remote databases. It's less common today to do this now that so many web sites have simply converted their databases to HTML and provided links from web pages. With telnet, you are remotely controlling a computer, which gives you access to its unique programs (a library catalog, for example, which might not be accessible via a web browser).
Some telnet sites:
Space Shuttle
Earth Observations Project's Photographic Data Base
Astronomical
Data Center (NASA)
Howard Community
College library
Howard
County library (has java-based and telnet access)
File Transfer Protocol (FTP)
FTP (file transfer protocol) is a way to transfer either computer files or text-based information over the Internet. Instead of providing space on an FTP server, many sites simply include the files on the same server that provides their web pages, and include hyperlinks on their pages that automatically download files. If you think of email as the U.S. Postal Service, FTP is UPS. FTP lets you stash large files in virtual "filing cabinets" for others to download. If you've ever downloaded a file off the internet (an upgrade to Netscape, for example), you've probably used FTP without knowing it. If you watch the address of the hyperlink for a downloadable file, it will probably begin with ftp:// instead of the http:// you're used to.
Some FTP sites:
More Music FTP sites
DEFCON linked FTP sites
Anonymous FTP sites
Valuable FTP sites
Two of the best sources for free software and shareware are Shareware.com and Download.com, which provide a searchable site for software you can download and use on your computer. Some of these sites are also excellent resources for updated drivers for your computer. We will talk more about shareware and freeware in the Hypermedia assignment.
To upload files using FTP, you will need a separate program such as FTPPro:
- Download FTPPro 2000 (try http://www.shareware.com)
- Install it on your system.
- Start FTPPro 2000. You have four window "panes" on your screen. The top left is your computer, and the top right is the contents of the folder you have selected on your computer (similar to Windows Explorer or My Computer). The bottom left is the computer you are connecting to. YOU NEED TO CHANGE THIS COMPUTER! To do this, go to step 4.
- Click on the menu item "Profiles". A dialog box appears.
- Click on "New Profile".
- Give your profile a name, such as "HowardCC WWW2 FTP Site."
- Enter the address: www2.howardcc.edu (do not put the CMSY192n)
- Check the "anonymous" box, then click on "add profile" at the bottom.
- The top line of your window should now say something like "1st Choice - HowardCC WWW2 FTP Site", and the first folder should be "atc", then "catalog", then "ccain", etc.
- Click once on the CMSY192n folder. A BUNCH of student stuff should appear in the right-side window.
- Go back to the top half of your screen and find the .txt file you are going to send to the HCC server. Don't forget to rename it something I can identify as yours! Click the file and drag it down to the CMSY129n folder. A dialog box will appear that will show the transmission.
- When it's finished, it should show the file list, including your file. You may need to "refresh" (on the menu bar).
Some Shareware and Freeware sites:
The Web's
Top Downloads
Shareware.com
Download.com
Tucows.com
The Free Site
USA
Today Compilation of Free Sites
ZIPped Files
Many files available on FTP sites (including many programs you can download for free or almost-free) come in a zipped file format with a ".zip" file extension. If you don't have WinZip on your computer, you can download PKZip (www.pkware.com) or WinZip from Shareware.com. The ZIP program will be able to uncompress files compressed by the user into a ".zip" format.
IRC and online chat
Basically, the internet is really just a complicated set of phone lines, so it's no surprise that chatting online is a big part of its use. Online chatting is talking to other people who are using the Internet at the same time you are. Usually, this "talking" is the exchange of typed-in messages echoing from the chat server and a group of users who take part from anywhere on the Internet. In some cases, a private chat can be arranged between two parties who meet initially in a group chat. Chats can be ongoing or scheduled for a particular time and duration.
Internet Relay Chat (IRC) is a worldwide multi-user chat network, similar to chat rooms in commercial online services such as America Online and Prodigy, except that IRC is basically free as long as you have a modem and access to the internet, you don't have to belong to an online service to participate, and IRC is unsupervised and unregulated.
IRC users communicate by sending typed lines of dialogue to each other. They meet in virtual chat areas called channels. You can start a chat group (a channel) or join an existing one. There are thousands of channels on the Internet, each with its own name, topic, and group of people. Internet Relay Chat (IRC)
It works basically like this: you run an IRC client program (such as mIRC), it connects your computer to a server, which in turn lets your computer connect with other servers around the world. After picking a channel from among the thousands of choices listed, you're online and talking in real-time.
There are various ways to chat online. You can use the regular IRC method, which can be very busy at peak times (it might take a long time for the conversation to scroll in the IRC client window). You can use an avatar-based program, such as The Palace. Or you can use a private chat room like the one set up for this class, which runs within your browser. The URL for this is emailed privately to students who register for CMSY129.
If you have a microphone with your computer system, there are options for voice chat as well.
Other utilities
The internet is not just serving up web pages and downloadable files, though. Some people have connected devices to the 'net that you can watch and/or manipulate:
Sydney University
Cappuccino Machine
Columbia University
Coke Machine
Around the World in 80
Clicks Web Cam
Discovery Online
Cams
HCC's web cam
Khep on the Web
PumaPaint
Australia's Telerobot
Paul's Hot Tub Status
Tate's Advent Calendar
Cheese-o-Matic
Virtual Graffiti
Mr. Wakeup
You may want to try ping, tracert, and finger as well.
Hypermedia, in the context of this course, is adding plugins to your browser that extend its capabilities into multimedia.
Plug-in applications are programs that, once installed, integrate with your web browser to provide additional features (sound, music, video, animation, interactive buttons, desktop publishing document layout, etc.). Some plug-ins will run their features outside the browser as well, but most plug-ins are created specifically for internet delivery.
Full programs that work both with and outside the browser as a separate program can be found online and downloaded to try or use for free – this is called shareware.
There are other types of experience enhancements, such as Virtual Reality Modeling Language (VRML sites such as AlphaWorld) and Digital Scents, which you may be interested in exploring as well.
Plug Ins
There are several popular plug-ins available on the internet. Some will self-install while you're on the sponsor's site; otherwise will require that you save the file to your hard disk and run the executable file (.exe file) to install the plug-in on your computer system. Once you've installed the plug-in, the feature should be available the next time you open your browser.
Shareware is software you can download and try out without paying up front. Some of the programs you will find will actually be "freeware" which costs you nothing, ever, but shareware often includes putting up with a nag screen that tells you if you liked the product to please send the programmer x amount of dollars. The example below shows the screen that pops up every time you quit PKZIP (until you register it of course, in which case you'd get a serial number from PKWARE that would make the nag screen go away). PKZIP is a very useful compression utility, by the way, and is available to download from PKWARE at http://www.pkware.com.
C|Net sponsors two popular sites to find software, Shareware.com and Download.com. Both can be searched for specific types of utilities or programs: Download.com is a repository of internet software and has more than 15,000 files available. Shareware.com has over 250,000 files available to download, including.freeware, shareware, demos, fixes, patches, upgrades, all provided by the top managed software archives and computer vendor sites on the Internet.
Some Shareware and Freeware sites:
The Web's
Top Downloads
Shareware.com
Download.com
Tucows.com
The Free Site
USA
Today Compilation of Free Sites
Some of the things you will find to download for free are games, screen savers, browsers, plugins, electronic texts, calculators, online photo album organizers, inventory tools, and updated hardware drivers. Some of the shareware options available include sophisticated calendar programs, online chat programs, HTML editors, . Some of the demo programs available will let you try out software that designs landscapes, shows you CPR techniques, track your ebay auctions, organize your recipes, play Christmas carols on your PC, and count calories.
Reading: URLS with information
on this subject
Self Test: Take the quiz for this unit
Assignments:
- File Transfer Protocol (FTP) (50 points)
Using View | Source in your browser, save a web site's HTML code to your hard disk and then upload the file to the class ftp site – more information is available here. - Online Chat (50 points)
Describe your experiences with online chat (class chat, mIRC, AOL Instant Messenger, or similar) using the online form submittal here. - Adding Programs to your System (100 points)
Download one or more plug ins or shareware programs off the internet, install them on your computer, and report your experiences on the online form here.
Click this link to review the grading system for this course
Deadline: Plan to
turn this in no later than January 25, 2002.
Email me:
if you have
questions about this assignment