What's It Really Like?

Chapter One
What's It Really Like?

Information superhighway. Cyberspace. The Virtual World. You would have to be a hermit not to hear these terms on an almost daily basis. But what do they all mean? If VRML, HTML, plug-ins, and other terms related to the Internet make you want to throw down your phaser and meekly run away to where no one's run before, stick around.

This is the place where it all begins; in this guide, the Internet starts to make sense. You can now put many of these terms together and make sense of them all. In this lesson, you can find answers to the following questions:

• How does the Internet really work?
• How is the Internet put together?
• What different types of things does the Internet enable you to do?
• What in the world is an Internet client?
• How are elements identified on the Internet?

If you think you already know the answer to these questions, you can skip ahead to the next lessons. You may want to read on anyway, however, because you might see the Internet presented in a way you've never seen before.

More Than a Highway

You don't need to be around the Internet for long to realize that the term Information Superhighway doesn't really explain the wonderful world of the Internet adequately. Using this term is kind of like using an ancient pulley system as an analogy for quantum physics.

What you need is a picture of the Internet that comes complete with whizzing electrons, fiber-optic cables, data transmissions at the speed of light, and all the other bells and whistles that are part and parcel of a miraculous system like the Internet.

Sounds sort of like the phone system, doesn't it? After all, because most Internet traffic basically travels over phone lines, such an analogy makes a lot of sense. Not convinced? A quick peek at Table 1.1 showing the similarities might win you over, as well as give you a more detailed preview of the rest of the lesson.

Table 1.1. The Internet and the phone system.

When you begin to really think about these systems, the similarities are striking. While you're going through this beginning lesson, continually make note of more specific similarities between the two systems to help you understand even better how the Internet works.

A System of Systems

One of the biggest misconceptions most people have about the Internet is that it is a "thing." They want to put it in a box and try to describe it as if it were a single mechanism instead of a collection of different parts.

Most people, however, have no such misconceptions about the phone system. In fact, talking about the phone system without using the word "system" would be almost impossible. In the same way, you should try to always think of the Internet as the "Internet system." This further highlights how very similar the Internet is to the phone system.

Making the Complex Simple

Imagine what type of system can connect and enable literally billions of people to communicate with each other worldwide almost instantaneously. Well, such a thing exists in the phone system and to a slightly but still lesser degree, the Internet.

How does a phone call (or a piece of e-mail) get from Hang-Gin Tien in California to Rhea LaStayt in New York? It is accomplished through a complex series of transmissions through many different stations. Figure 1.1 shows how such a transmission might occur for a typical phone call.

Figure 1.1.

A typical phone call can actually "stop" at dozens of relay stations before reaching its destination.

Of course, Figure 1.1 represents a vast simplification of what really happens during a phone call. Each of the points shown as a station in the figure performs a number of functions. Tasks such as deciding which station the current call will go to next, logging the call for record-keeping, and determining what type of call is being transmitted are performed at each station. These functions are completed by a number of wires, relays, and yes, computers, at each station a call passes through.

It's hard to imagine that all this work can happen in the same amount of time that a baseball player takes to swing his bat, but it does.

Now take a look at Figure 1.2. Not a lot of differences in the two, are there? Generally, the computer (or computers) at each routing station on the Internet are referred to as nodes.

Figure 1.2.

The methods of transmission for phone calls and e-mail messages are almost identical in nature.

These nodes perform many of the same functions that phone routing stations do. What type of data is being transmitted? Where is it going? Which node will the data go to next? Is all the data here? These questions are some of the many that an Internet node asks and answers with every transmission.

All Those 0s and 1s

One difference does exist in the way data is transferred over these vast networks of computers and wires, and it is in the form that the data takes. A typical phone call transmits analog data in a steady stream, whereas a typical computer transmission is carried out as digital data in short bursts. You can think of a digital data transmission as a series of bullets being fired from a gun.

New Term: Digital: All digital data is made up of a series of 0s and 1s that are grouped in unique sequences. Each sequence of 0s and 1s can mean an infinite number of things to the computers translating them into what you see on your screen.

Any ballistics expert can tell you that every bullet has its own distinct fingerprint. Well, so does every "bullet" (referred to as a packet) of information sent over the Internet.

New Term: Packet: A packet is a single sequence of digital data. As each packet of data is sent through the various networks, it has a distinct digital "marker" that tells the routing computer which "gun" it belongs to, as you can see in Figure 1.3.

Sending data in packets offers enormous advantages during transfer. If an interruption occurs in transmission, for example, a computer can simply hold all the packets with identical markers until all the packets have arrived and then put them back together again, as illustrated in Figure 1.3. Sending data this way also means that multiple computers can send packets through the same wire at the same time (because they can be reconstructed at the other end according to their markers). Both of these factors contribute to faster and more reliable data transmission.

Figure 1.3.

No matter how packets get mixed up in transmission, they usually can be put back together again by a computer.

This method of handling data does, of course, begin to blur the lines between all types of data transfer. Even today, many phone calls are digitally switched to allow faster and more reliable transmission than ever before. Soon, phone and Internet data transmission will be handled the same way.

You Just Can't Stop It

You should make note of one last point before moving on to the next item. Because the Internet, like the phone system, is a system, you can't "take it down." If a tornado comes out of the sky and destroys a call routing station in Detroit, the system as a whole really isn't affected. That area may see a temporary lapse in service, but calls will be rerouted and the system will continue to run relatively smoothly.

On the Internet, the same is true. One computer, or even a whole set of computers, going offline may affect some users, but it won't damage the integrity of the system. As an example, America Online's computers recently went down for 19 hours, leaving 2 million users without Internet access. Users of other systems didn't even know about the situation until they read it in the paper the next day.

This happens because each computer or computer system on the Internet is, in a manner of speaking, self-sufficient. Of course, much as planes are often rerouted through different airports because of bad weather, so too can Internet traffic be rerouted. In the end, just remember that the Internet functions as an organism, not an organ.

A Variety of Functions

The first apparent benefit of any system is that it has allowances for a variety of functions. The body is a system: It can talk, it can walk, it can hold objects, and it can process information and a million other tasks.

The phone system, of course, works the same way. You can perform more than one task with it. Obviously, you can make phone calls. You also can send faxes and transmit videos using a video phone. If you're hearing-impaired, you can use a TTY machine and make phone calls from a typewriter. In addition, a host of other services are conducted over the phone system: fax-back, 800 and 900 services, and voice-mail messaging systems, to name just a few.

The same is true of the Internet. Because it is a system, you can perform a myriad of different tasks with it. You can send e-mail (Lessons 5-8), read and distribute news (Lessons 9 and 10), participate in real-time communication (Lessons 11 and 12), use the World Wide Web (Lessons 13-16), transfer files (Lesson 18), and more.

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CAUTION: Remember that no analogy is perfect. You may think that the Internet seems a lot like the phone system. It is. Remember, however, a lot of differences exist between the two of them as well. One of the biggest is difficulty level. You probably don't need a 300-page guide to place a phone call and send a fax; however, you might need such a guide for using fax-back and complicated voice-mail systems. Similarly, you need a guide that not only lays a foundation for understanding the Internet, but gives you the extra knowledge to handle more complex parts, as well.

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The Client/Server Relationship

So far, you've learned that the Internet is a system that can perform a variety of functions. So what is the next step? Let me answer this question with yet another question: What do you normally need to perform any function? Answer: Equipment. In the following sections, I describe the standard and functional equipment you need to use the Internet.

It's Standard

If someone were to ask you what equipment you need to conduct business on the Internet, you would probably say, "A computer, a modem, and some type of connection." You'd be right, of course. But what you've really described is just the standard basic equipment needed to cruise the Internet. Although you do need these things, they aren't really the key "equipment" used on the Internet.

To explain, let me go back to the phone system again. Imagine that you have just moved into a brand new house. You're sitting on your nice new furniture, you've had the phone company give you a phone number, and your wall jacks are installed with a phone cord dangling from them. Is all this equipment sufficient for you to place a phone call? No. Obviously, you need a phone. You need that last piece of equipment necessary to "complete the circuit," so to speak. In this instance, the wall jack, cords, and phone number service are just basic prerequisites you need before you can actually start placing calls. The same is true of the Internet: Computers, modems, Internet service providers, and a telephone connection are just the basics.

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Time Saver: Just because the equipment I just mentioned is basic doesn't mean it's not important. Generally, the more RAM you have, the faster you can go--16MB is almost a minimum now. The more megahertz on your PC, the faster you can go; Pentiums running at 100, 133, and even 166 megahertz are now common. The higher your modem speed, the faster you can go--28.8Kbps modems are now standard. Rule of thumb? The faster, the better.

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New Term: Megahertz (MHz): One hertz represents a single cycle of current per second in a circuit. A cycle is merely the time it takes an electron to make a "trip" between two points in a circuit. A megahertz represents 1,000 cycles per second. PC speed is usually gauged in megahertz, so a 66MHz processor can complete 66,000 cycles in one second.

Getting the Job Done

Now that you know the basics, you're ready for the functional equipment I talked about earlier. On a phone system, the functional equipment is a phone, a TTY machine, a video phone, or a fax machine.

On the Internet, however, the functional equipment you use isn't a piece of hardware that you can touch or feel, like a phone is. Rather, the functional equipment on the Internet takes the form of a piece of software. This piece of software, which is possibly the most important piece of all, is called a client.

New Term: Client: All the computers and software that make up the Internet are either clients (which receive and translate data) or servers (which provide and translate data). Thus, by using client software, you can get information from the Internet.

Suppose that you go into a restaurant and order a meal. Several minutes later, a "server" delivers food to your table and you begin to eat. You have just entered into a client/ server relationship. You requested food, this request was communicated to a server, and the server fulfilled your request, at which point you consumed the food.

The Internet works exactly the same way. The difference is that, instead of ordering food from a restaurant, you order information from a computer. And just as you can order steaks, salads, desserts, or drinks from a restaurant, you can order e-mail, Gopher sites, World Wide Web pages, and more from Internet servers. Simple, huh?

The Final Piece to the Puzzle

In a restaurant, you order the food, whereas on the Internet, you need to have a piece of software do it for you. Why is that? Well, return to the restaurant example again.

Suppose that you walk into a Japanese restaurant where the menus are written in Japanese and the servers don't speak English. What would you do? You would either have to leave or ask an interpreter to order for you. If you ask an interpreter, you can tell him or her what you want and then he or she can place the order for you.

Because you already know that you don't speak "Internet" (all those 0s and 1s sent in packets), you need an interpreter (Interneterpreter?) to help you. Enter the software client.

Let's See Some ID

The last piece of the puzzle is how the Internet keeps track of all the different client and server computers on the Internet. Once again, using the phone system as an example helps. What one thing do you need more than anything else to call another person on the phone? Easy, the person's phone number. Without it, you're lost.

And Your Address Is...

As many phone numbers exist as do phone lines in the world; each one different, each one unique. Every computer on the Internet also has a unique number, and it's called the IP address.

New Term: IP address: This address is used by Internet Protocol (IP) to identify each computer on the Internet. An IP address consists of four numbers between 0 and 255, each separated by a period. A typical IP address might be 35.8.7.92.

But how do computers get IP addresses? An organization called InterNIC gives them to various Internet service providers, or ISPs. (See InterNIC's home page in Figure 1.4.) These ISPs then distribute the addresses to computers on their networks.

Figure 1.4.

InterNIC is responsible for registering all computers on the Internet with IP addresses.

Just as a particular neighborhood might have all its phone numbers begin with 555, so too might all the computers connecting to a particular ISP start with 35.8. In fact, InterNIC usually gives out IP addresses in bundles. Company X, for example, might buy all the IP addresses beginning with 192.63.7 so that it can assign 255 different IP addresses, either permanently or temporarily.

Master of Your Domain

One more point and then you're done for now. If you've watched any TV lately, you may have seen statements like "Find us on the Internet at www.companyx.com." Given these weird-looking addresses, you might be wondering what happened to Company X's IP address.

Let me assure you that it's still there. Just like the SliceNDice Diceit Kitchen Knife Company tells you that its phone number is 1.800.SLICEIT so that you can remember it, the Internet uses domain names to "hide" the hard-to-remember IP addresses. After all, would you rather remember 192.63.7.45 or www.companyx.com?

New Term: Domain name: Also registered by InterNIC, the domain name is an "English version" of an IP address. Some computers (called Domain Name Servers) even translate domain names into IP addresses for fast access on the Internet.

Summary

Congratulations! Now you know more about how the Internet really works than a majority of the American population. Beyond the cold facts, you should have a grasp of what is really happening when you send that e-mail message or download that Web page.

You know that the Internet is a system and not a "thing." You should realize that data is transmitted through this system via a complex network of wires, computers, and nodes and that this transmission requires certain equipment, both standard and functional, in order to work properly.

Internet equipment consists of both hardware and software, and software clients translate the language of the Internet into a form you can read on your screen. You also know that, as a result of this complex system, you can perform a variety of different tasks on the Internet, from sending e-mail messages to cruising the World Wide Web.

Finally, you now know that every computer on the Internet has a unique ID called an IP address. You also see that domain names are put in place so that you don't have to remember all the IP addresses.

To further help you understand these concepts, you should go through the following workshop.

Workshop

The following workshop helps solidify the skills that you learned in this lesson.

Q&A

Q What are the basic building blocks of packets?

A Packets are made up of a number of 0s and 1s in a unique sequence that conveys certain information. A portion of these 0s and 1s makes up a marker that identifies a packet as belonging with all other similar packets.

Q Why is InterNIC responsible for assigning IP addresses and domain names?

A Basically, to avoid a lot of confusion. Can you imagine what would happen if every local phone company got to pass out phone numbers? They would have no way to avoid duplication of numbers and no way to route calls to unique numbers. The same is true of IP addresses. InterNIC acts as the administrator to make sure that the Internet runs smoothly.

Q Can clients and servers be either software or hardware?

A Yes. Server computers are generally loaded with server software to help them "serve" their information better. When you use the Internet, not only are you using client software to give you the information you need, but your PC also acts as a client computer at the same time.

Quiz

Take the following quiz to see how much you've learned.

Questions

Answers

Activities

The next time you sit down to watch TV, grab a pencil and paper. Then stick around during commercials. Make note of how many companies have a domain name. Jot down some of them so that you can explore them in a later lesson. As an added activity, see whether you can figure out how many possible IP addresses exist on the Internet. (The answer is in the first section of the next lesson.)