Roadmap96: MAP03 - Levels of Internet Connectivity | WebReference

Roadmap96: MAP03 - Levels of Internet Connectivity


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"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 Roadmap96 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, and you will find that it's going to save you a lot of heartache and confusion in the long run. It may also persuade you to go out and get a PPP or SLIP connection.

There are generally three levels of Internet connectivity, although there are several variations of 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 has shown that I must make the following distinctions 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, or the recent expansion of some BBSs into a combination Level One and Level Two access. Please recognize that I have purposely taken some editorial liberties in this lesson to make it easier to understand for the new users (a.k.a. "newbies").



Level One connectivity ("gateway access") is access to the Internet from a network that really is not 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 available on the Internet. With Level One connectivity, you are limited in what you can access on the Internet by what your service provider allows you to access.

Good examples of networks with Level One connectivity are America Online (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 (like the chat rooms), but ALL of these programs run only on the AOL network.

AOL subscribers, and subscribers to most of the other commercial on-line services, are lucky in that they can access SOME of the tools on the Internet through their gateway. Many people with Level One connectivity only have e-mail access (by the way, if you have Level One connectivity, do not worry -- in this workshop I will 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 connectivity ("remote modem access") is access through a dial-up terminal connection. This is when, by use of a modem, a "host" is accessed and your computer acts as if it were a terminal directly connected to that host. The host that you connect to is actually "on" the Internet, i.e. it is connected to the Internet by a full time "level three" connection (see the next section, "Level Three Connectivity," for details).

You may type the commands on your own computer, but it is the host that carries out your commands. Your computer is, in effect, just a "dumb" terminal connected to the host. Level Two connectivity is the most popular in the sense that more people have Level Two connectivity than any other level of connectivity. Level Two connectivity is also 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. What if, for example, you hear of this hot new client called "CU-SEEME" that you want to try it out? Well, if your host does not have a CU-SEEME client on it, you are out of luck! Putting a copy of the CU-SEEME client software on your own computer will do NOTHING for you -- remember the only programs you can use when you have Level Two connectivity are the programs that the host has!

As well, with Level Two connectivity you must always remember that everything you are doing is done through the host, NOT through your own computer. If you download a file from somewhere (as we did last Friday with the GET command) that file will go to the host, NOT to your own personal computer. You will 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 ISP can tell you more about this).



Level Three connectivity ("direct Internet access") is the highest, and most expensive, level of connectivity. With Level Three connectivity, your computer is directly wired into the Internet using high-speed lines, and is on-line twenty-four hours a day, seven days a week. Level Three connectivity is great if you have 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 personal computer.

Besides, Level Three connectivity is so incredibly expensive. For example, the University of Alabama pays $29,000.00 (US) every year just to connect to the Internet, and that doesn't include the software, hardware, facility, and staff expenses. Until recently, Level Three connectivity was limited to large corporations and universities who could afford the cost. 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 advances in modems and telephone lines, however, there is a new branch of Level Three connectivity called "On-Demand Direct Connectivity." Since you probably aren't going to spend 24 hours a day on the Internet, there are some sites out there that will let you connect directly 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 your computer isn'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 between $20 and $40 a month -- that's about $29,547,952.00 Canadian (I'm kidding)). The second cool thing about PPP and SLIP connections is that all of the client software is stored on YOUR personal computer. Want to play with CU-SEEME? Load it onto your computer and play with it. You cannot do this with any of the other levels of connectivity.

When I wrote this original version of this workshop back in the Fall of 1994, PPP and SLIP connections were a pretty scarce commodity. Now, they're everywhere, and it won't be too long until the number of people with SLIP and PPP connections far surpass the number of people with Level Two connectivity.

How can you get a SLIP or PPP account? Ask around! Chances are, at least one Internet Service Provider (ISP) in your town is offering pretty cheap SLIP or PPP accounts. You might also want to pay a visit to your local computer store -- they can tell you not only which service providers offer SLIP and PPP, but also which service providers their customers recommend.



I want you to find out what level of Internet connectivity you have. Remember, please do not send your answers to me.


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.

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Originally written by Patrick Douglas Crispen