Understanding the Internet

The Internet began in the late 1960s as an experiment by the U.S. Department of Defense to see if a non-centralized network could be built to withstand the destruction of one or more of its parts. Unlike previous networks, this new network did not have a single central point. Instead, all sites on the network were interconnected.

Out of this network came a protocol for linking computers together. A protocol is a set of standards for how network communication takes place. The protocol is called TCP/IP (Transmission Control Protocol/Internet Protocol). This protocol is the standard that makes it possible for different computers all over the globe to talk to each other. The TCP/IP protocol is the foundation of the Internet.

At first, the Internet was used solely by the government, but soon universities and other institutions connected themselves to the Internet to communicate with one another and collaborate on projects. The Internet grew to connect hundreds of different sites all across the world. Each organization on the Internet was responsible for maintaining its part of the network, so the Internet was not owned or controlled by any one organization.

Today, the Internet connects up to 40 million people around the globe and is growing by as much as 10% per month.

Getting connected

The Internet is like a system of roads, freeways, and bridges. Although the term "Information Superhighway" is over-hyped, it is a decent metaphor for how the Internet works. From any road in any city, you can get to almost any other road in any other city. From my computer at my desk, I can send an electronic mail message to someone sitting at a computer in Helsinki, Taipei, or Biloxi.

Internet access companies or Internet Service Providers provide "onramps" to the Information Superhighway -- physical connections that allow you to access the Internet. These onramps are called "POPs," which stands for "points of presence."

Your computer uses a modem to dial into a POP which connects you to the Internet. Once connected to a POP, you have access to all the resources of the Internet. Most ISP's will also supply you with software available for "surfing" the Internet: a Web browser.

The Birth of Domain Names

In the 1980's, a major shift occurred as a result of the increase in scale of the Internet and its associated management issues. To make it easy for people to use the network, hosts were assigned names, so that it was not necessary to remember the numeric addresses. Originally, there were a fairly limited number of hosts, so it was feasible to maintain a single table of all the hosts and their associated names and addresses. The shift to having a large number of independently managed networks (e.g., LANs) meant that having a single table of hosts was no longer feasible, and the Domain Name System (DNS) was established. The DNS permitted the conversion of a numeric host address (i.e, 215.72.87.66) to a simpler, easier to remember name address (www.bobswebsite.com).

The Birth of the Web Browser

In October of 1994, Mosaic Communications Corporation (renamed "Netscape Communications" on 11 November 1994) introduced the first public beta of their browser, "Mosaic NetScape." This was one of the first web browsers to be freely distributed across the Internet.

How does my email work?

Let's say you're sending mail to joy@aol.com. When you've finished composing your email, your mailer (email software) performs a gethostbyname system call to look up the IP address of the remote host (aol.com).

Normally the host would be looked up from /etc/hosts, but since you're on the Internet, your system queries an Internet name server to find the address of aol.com.

Your mailer opens a virtual circuit over the Internet to "joy's" mailer. It communicates with the remote mailer by using the Simple Mail Transfer Protocol (SMTP).

If all goes well, the mail is usually delivered within a few seconds, even if the recipient's machine is on the other side of the world.

If the remote site is down, your mailer will keep trying every hour or so, usually for a couple of days.

If the site still can't be reached, the mail will be returned to you as "undeliverable."

People and organizations without fulltime Internet connections may also use the Post Office Protocol (POP).

How do I create a domain name?

Option 1

• Go online to either InterNIC (www.internic.com) or a name registration service such as www.register.com and perform a name search to make sure the domain you want to establish is available.
• After confirming the availability of your domain name, complete the online registration form to secure your name.

Option 2

• You select an Internet Service Provider to host your website.
• The service provider registers your company with the InterNIC -- the Internet's Network Information Center.
• A unique domain name, of your choosing, is assigned to your business or organization. For example, sun.com, indiana.edu, nasa.gov, neosoft.com.
• One or more IP network numbers are assigned to you. For example, 198.64.6. Internet zone tables are updated to include your domain name, the mapping between your domain name and network numbers, and to show that the route to your network is through your service provider.

What should it cost to have my own website? 

Hosting fees will vary based on your individual need for space, download capacity, security and special programming requirements. In general, the monthly hosting fee for a basic web site account should cost between $25 and $50 a month.

Free Hosting Services

There are a variety of places on the Internet that offer hosting at no charge. Before you decide to host your website with one of these services, be sure you understand the fine print of your hosting agreement. In general free hosting services are free because of the following:

• You will be required to place banner advertisements on either the top or bottom of each page of your website. In some cases you will be required to place banner advertisements on both the top and the bottom of your web pages.
• The activities of visitors to your website will be tracked via Cookies or other online software. Their activities on the Internet will be monitored and the data collected will be sold to marketing services.

About Modems And Telephone Lines 

Telephone lines were designed to carry the human voice, not electronic data from a computer. Modems were invented to convert digital computer signals into a form that allows them to travel over the phone lines. Those are the scratchy sounds you hear from a modem's speaker. A modem on the other end of the line can understand it and convert the sounds back into digital information that the computer can understand. By the way, the word modem stands for MOdulator/DEModulator.

Buying and using a modem used to be relatively easy. Not too long ago, almost all modems transferred data at a rate of 2400 Bps (bits per second). Today, modems not only run faster, they are also loaded with features like error control and data compression. So, in addition to converting and interpreting signals, modems also act like traffic cops, monitoring and regulating the flow of information. That way, one computer doesn't send information until the receiving computer is ready for it. Each of these features, modulation, error control, and data compression, requires a separate kind of protocol and that's what some of those terms you see like V.32, V.32bis, V.42bis and MNP5 refer to.

If your computer didn't come with an internal modem, consider buying an external one, because it is much easier to install and operate. For example, when your modem gets stuck (not an unusual occurrence), you need to turn it off and on to get it working properly. With an internal modem, that means restarting your computer--a waste of time. With an external modem it's as easy as flipping a switch.

Here's a tip for you: in most areas, if you have Call Waiting, you can disable it by inserting *70 in front of the number you dial to connect to the Internet (or any online service). This will prevent an incoming call from accidentally kicking you off the line.

This table illustrates the relative difference in data transmission speeds for different types of file sunder the best of circumstances. A modem's speed is measured in bits per second (bps). A 14.4 modem sends data at 14,400 bits per second. A 28.8 modem is twice as fast, sending and receiving data at a rate of up to 28,800 bits per second.

Many things can interfere with the speed of a file transfer. These can range from excessive line noise on the telephone line, the speed of the web server from which you are downloading files, the number of other people trying to access the same file and the overall traffic on the Internet.
Until the end of 1995, the conventional wisdom was that 28.8 Kbps was about the fastest speed you could squeeze out of a regular copper telephone line. Today, you can buy a modem capable of a data transmission up to 56 Kbps. The key question for you is knowing what speed modems your Internet service provider (ISP) has. If your ISP has only 28.8 Kbps modems on its end of the line, you could have the fastest modem in the world, and only be able to connect at 28.8 Kbps. Before you invest in a 56 Kbps modem, make sure your ISP supports them.

DSL

DSL (Digital Subscriber Line), a high-speed technology, is becoming increasingly popular. A DSL line can always remain connected to the Internet, so you don't need to dial-up. Typically, data can be transferred at rates up to 1.544 Mbps downstream and about 128 Kbps upstream over ordinary telephone lines. Since a DSL line carries both voice and data, you don't have to install another phone line. You can use your existing line to establish DSL service, provided service is available in your area and you are within the specified distance from the telephone company's central switching office.

DSL service requires a special modem and a network card in your computer. Prices for equipment, DSL installation and monthly service can vary considerably, so check with your local phone company and Internet service provider. The good news is that prices are coming down as competition heats up. Some companies now provide free installation and equipment when you sign-up for a year of service.

Cable Modems

Another new development is a device that provides high-speed Internet access via cable TV. With speeds of up to 36 Mbps, cable modems can download data in seconds that might take fifty times longer with a dial-up connection. Because it works with your TV cable, it doesn't tie up a telephone line. Best of all, it's always on, so there is no need to connect--no more busy signals! This service is now available in some cities in the United States and Europe.

ISDN

In some parts of the U.S., phone companies offer a technology known as ISDN. ISDN requires a so-called ISDN adapter instead of a modem, and a phone line with a special connection that allows it to send and receive digital signals. An ISDN line has a data transfer rate of between 57,600 bits per second and 128,000 bits per second, which is at least double the rate of a 28.8 Kbps modem. You have to arrange with your phone company to have this equipment installed.

Making Business Connections

Leased lines come in two configurations: T1 and T3. A T1 line offers a data transfer rate of 1.54 million bits per second. A T1 line is a dedicated connection, meaning that it is permanently connected to the Internet. This is useful for web servers or other computers than need to be connected to the Internet all the time. It is possible to lease only a portion of a T1 line using one of two systems: fractional T1 or Frame Relay. You can lease them in blocks ranging from 128 Kbps to 1.5 Mbps. The differences are not worth going into in detail, but fractional T1 will be more expensive at the slower available speeds and Frame Relay will be slightly more expensive as you approach the full T1 speed of 1.5 Mbps. A T3 line is significantly faster, at 45 million bits per second.

Leased lines are expensive and are generally only used by companies whose business is built around the Internet or need to transfer massive amounts of data. Check with your local phone company for availability in your area.