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- MAP03: LEVELS OF INTERNET CONNECTIVITY
- --------------------------------------
-
- "A journey of a thousand miles must begin with a single
- step." -- Lao-Tsu, The Way of Lao-Tsu
-
-
- Welcome back to the first full week of the Roadmap workshop! It looks
- like we survived another weekend without a squirrel attack. Yay :)
- (by the way, the :) is an "emoticon" smile; put your left ear on your
- left shoulder to see it). Today's lesson is really simple, but you'll
- find that it's going to save you a lot of heartache and confusion in
- the long run (it may also convince you to go out and get a PPP or SLIP
- connection).
-
- There are generally three levels of Internet connectivity (although there
- are several variations on the three levels). For our purposes, I am
- just going to call these three levels "Level One," "Level Two," and
- "Level Three."
-
- Before I talk about the three levels of connectivity, experience shows
- that I have to say the following to keep myself from being overrun
- with e-mail: the "three level approach" to Internet connectivity is
- a very simplified view of the different ways that you can access the
- Internet. It does not take into account UUCP, TIA, Trumpet Winsock,
- or the recent expansion of some BBS' into a combination Level I and
- Level II access. This oversimplification is on purpose. Please recognize
- that I have taken some editorial liberties in this lesson to make
- the lesson easier to understand for the new users (aka. "newbies").
-
- Level One connectivity ("access through a gateway") is access to the
- Internet from a network that really isn't "on" the Internet. Picture
- two circles that touch each other at only one point. One of the circles
- is the Internet, the other circle is a non-Internet network, and the
- point where the two networks touch is called a gateway. The gateway allows
- the two networks to "talk" to each other, but users of the non-Internet
- network are limited in their ability to fully access all of the tools
- of the Internet. With Level One connectivity, you are limited to what
- you can access on the Internet by what your service provider allows
- you to access.
-
- A good example of networks with Level One connectivity is America
- On-Line (AOL), Compuserve, Prodigy, and many of the other commercial
- on-line services. AOL is, in effect, its own little network. It has a
- great number of different programs that its subscribers can use, but ALL
- of these programs only run on the AOL network.
-
- AOL subscribers, and the subscribers to most of the other commercial
- on-line services, are lucky in the fact that they can still access SOME
- of the tools of the Internet through their gateway. A lot of people
- with Level One connectivity only have e-mail access (by the way, if
- you have Level One connectivity, do not worry -- I'll show you how
- to access a lot of the Internet's tools using e-mail (it's not easy,
- but you can do it)).
-
- Level Two Internet access ("remote modem access") is access through a
- dial-up terminal connection. This is where, through the use of a modem,
- you access a "host" and your computer acts like it is a terminal
- on that mainframe. You may type the commands on your own computer, but
- it is the host that carries out your commands.
-
- Level Two connectivity is the most "popular" (in the sense that more
- people have Level Two connectivity than any other level) and the most
- misunderstood level of connectivity.
-
- To begin with, Level Two connectivity limits you to using the
- programs (also known as "clients") that are running on the
- host. If, for example, you hear of this hot new client called
- "Mosaic" and you want to try it out, if your host does not have
- a Mosaic client on it you are out of luck! Putting a copy of the Mosaic
- client software on your own computer won't do ANYTHING for you --
- remember that the only programs that you can use when you have
- Level Two connectivity are the programs that the host has!
-
- Also, with Level Two connectivity you must always remember that
- everything you are doing is through the host, NOT through your
- own computer. If you download a file from somewhere (like we did
- last Friday with the GET command) that file will go to the host,
- NOT to your own personal computer. You'll need to download the file
- one more time -- this time from the host to your computer --
- if you want the file to be on YOUR computer. (Your local Internet
- provider can tell you more about this).
-
- Level Three connectivity ("Direct Internet Access") is the highest, and
- most expensive, level of connectivity there is. With Level Three
- connectivity, you are directly wired into the Internet using high-speed
- telephone lines, and you are "on-line" twenty-four hours a day, seven
- days a week. Level Three connectivity is great if you are a mainframe
- or a major site with hundreds of users, but is not too advantageous
- if you are a sole user with a beat-up PC.
-
- Besides, Level Three Internet access is so incredibly expensive (1)
- (the University of Alabama pays $29,000.00 (US) each and every
- year just to connect to the Internet, and that doesn't include
- the software, hardware, facility, and staff expenses) that, until
- recently, Level Three connectivity was limited to large corporations
- and Universities. Also, because Level Three connectivity is limited
- mostly to mainframes, you as a user are still limited to using the
- programs that are already loaded on the mainframe.
-
- Thanks to some recent breakthroughs in modems and telephone lines, there
- is a new branch of Level Three connectivity which is called "On-Demand
- Direct Connectivity." Since you probably aren't going to spend
- twenty-four hours a day on the Internet, there are some sites out there
- that will let you connect to the Internet whenever you want using a
- high speed modem and something called "Point to Point Protocol (PPP)"
- or "Serial Line Internet Protocol (SLIP)" connection.
-
- There are two cool things about PPP and SLIP connections. First, because
- you aren't connected to the Internet all day long, it doesn't cost as
- much as regular Level Three connectivity (you can find sites that will
- only charge you about $40 or $50 US (that's about $29,547,952.00
- Canadian -- I'm kidding :) -- month for a PPP or SLIP connection).
- The second cool thing about PPP and SLIP connections is that the
- client software is stored on YOUR computer. Want to play with
- Mosaic? Load it onto your computer and play with it (you can't do
- this with any of the other levels of connectivity).
-
- The one bad thing about PPP and SLIP connections is that they are
- a relatively scarce commodity. Not may Internet service providers
- offer PPP and SLIP connections, but the number of providers offering
- PPP and SLIP connections will certainly increase over time :)
-
- In review, there are three levels of Internet connectivity:
-
- LEVEL DESCRIPTION COMMENTS
-
- One Access through a Gateway Limited Internet access
-
- Two Remote modem access Most "popular"
- Commands executed by host
- All programs on host
- Can only run client software
- already on the host
- All files on host unless
- you download to your computer
-
- Three Direct Access EXPENSIVE! (1)
- 24 hour connection
- All software on mainframe
-
- -- PPP/SLIP Not all that expensive
- Connect when you want
- Client software on YOUR computer!
-
-
- TOMORROW: E-mail!!
-
- HOMEWORK:
-
- I want you to find out what level of Internet connectivity
- you have. (Remember, please don't send your answers to me).
-
- NOTES:
-
- (1) While non-profit organizations can get direct access for about
- $6500 (US) a year, this price is still outside of the budget of
- most people.
-
- SOURCES:
-
- I want to thank Liz and Gerald Lawley at Internet Training and Consulting
- Services, a professional Internet training company here in Tuscaloosa, for
- their help with this lesson. The idea for this lesson came from a recent
- conversation I had with Liz and Gerald, and an ITCS training guide served
- as the outline for this lesson. I can not thank Liz and Gerald (and ITCS)
- enough for their continued help and support.
-
-
- PATRICK DOUGLAS CRISPEN THE VIEWS EXPRESSED IN THIS LETTER DO NOT
- PCRISPE1@UA1VM.UA.EDU NECESSARILY REPRESENT THE VIEWS OF THE
- THE UNIVERSITY OF ALABAMA UNIVERSITY OF ALABAMA - TUSCALOOSA
-
- ROADMAP: COPYRIGHT PATRICK CRISPEN 1994. ALL RIGHTS RESERVED.
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