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What, Exactly, Is the Internet?

The largest and most successful TCP/IP network ever built is the Internet. Within just a few short years, the Internet has gone from a quirky, complex network with arcane tools that only a geek could love, to a powerful, global utility that features user-friendly tools for all. Today's TCP/IP networks users have it so easy that they almost don't realize when they are using a network.Internet service providers (ISPs)who shall remain nameless but whose name likely contains three initialswould have you believe based on their advertising and service, no single ISP has every host and every user connected to its network.

The Internet services industry has consolidated quite a bit, but there are probably still more than 10,000 ISPs around the world. Even though all sell essentially the same service, each ISP tries to differentiate itself from its peers through marketing and customized services. This is especially true of the large ISPs and the small ones that serve only local markets.

All ISPs Are Not Created Equal

Some ISPs focus on providing high-bandwidth pipes to businesses. Others specialize in providing low-bandwidth connections to residential consumers. Still others focus on residential consumers in general and try to add value beyond the connection. In general terms, these types of providers function as on-ramps to the Internet and are often referred to as such.

Some on-ramp providers try to lock you into their service by offering proprietary chat and instant messenger services. Others focus on hosting services. The one thing that all these types of ISPs have in common is that they don't cover the world.

You can think of the top-level providers as an ISP for ISPs. This small group provides Internet connectivity to smaller or regional ISPs. They form the backbone of the Internet and, as a result, are sometimes referred to as Internet backbone providers. To give you a visual of how all this fits into perspective, take a look at Figure 13-1.

As you can see in Figure 13-1, the Internet is made up of lots of ISPs organized into functional tiers. Some providers play a game as they strive to appear bigger than they really are. For a while, the investment community favored Tier 1 ISPs as less risky than Tier 3 ISPs.

Although nobody ever clearly delineated what separates the tiers, Tier 1 was universally accepted to mean a backbone provider and Tier 3 was accepted to mean an on-ramp. Tier 2 generally means an ISP with a presence in multiple regions and a limited backbone interconnecting those regional networks. The distinctions between these three tiers became blurry over time because many providers embodied aspects of all three.

The important point here is that no single ISP can offer you universal connectivity alone. Even though any given pair of ISPs compete, they rely upon each other to support the Internet user community's need to reach every possible destination via one network connection. That's the real beauty of the Internet: For ISPs, it is simultaneously a competitive yet cooperative environment.

Notice that Figure 13-1 is illustrative in nature and not an attempt to show you the actual architecture of the Internet. In general terms there are a lot of Tier 3 providers, an order of magnitude fewer Tier 2 providers, and just a handful or so of true Tier 1 providers.

Now that you know a little bit more about how the Internet is pieced together and have seen that not all ISPs are created equal, the important decision facing you is how to pick an ISP.

Picking an ISP

Almost everyone is affected by peer pressure and ISPs know this. They know that anyone can respond to a media advertisement or be swayed by the influence of a friend or family member. In fact, some ISPs count on that to increase their subscriber base and convert those new users into long-term users. That's just good business. What's good for an ISP might not be good for you! Your approach to selecting an ISP should be more of a logical process than a falling-for-peer-pressure process. You should understand your needs and then search for an ISP that can satisfy you.

You already walked through some of the differences between ISPs, and in those differences lie the clues to your decision-making process:

Find an ISP that provides service in your area.

Consider the access technologies that the ISPs in your area support. One question you need to answer is whether they support residential consumers. Remember: Not all on-ramp ISPs market to homes. Some only market high-speed connections for enterprises. Do they support only dial-up or can you get a faster connection? Is a faster connection important to you?

Consider what, if any, amenities are offered by those ISPs. ISP amenities are things like a home page environment, utilities for contacting and interacting with others on the net (such as instant messaging or chat), and whether those are important to you.

For some users, a high-speed connection without any home environment is perfectbut that's me. You need to evaluate your particular needs and weigh your options carefully. For example, you might actually have friends, in which case knowing when they are online might be important to you.

How solid are they financially? The Internet as an industry has undergone tremendous consolidation in the last five years. Many ISPs are no longer around and many are still around but not necessarily here to stay.

You can take some comfort in knowing that of all the assets an ISP has, its customers are its most valuable. In a merger, acquisition, or bankruptcy, it is the customer base (not circuits, shareholders, hardware, or employees) that is most highly valued. This criterion should be the least of the data points that you consider when making this decision, but it should be one of your data points. No sense in signing on for a year's service when the ISP is about to shut its doors. Especially if they are offering discounts if you pay for that year's worth of service in advance!

There are many telltale signs of an ISP in trouble, not the least of which is the financial information that a publicly traded company must publish. If your ISP has been losing money for several quarters in a row, if its stock price is sinking steadily, or if it has been making local headlines for laying off employees, you should beware! If it is a company you wouldn't invest in, you should be wary of being its customer, too. Generally speaking, smaller ISPs are more vulnerable than larger ones, but even major ISPs have gone bankrupt during the implosion of the ISP industry. Caveat emptor!

Picking an Access Technology

Before you can use the Internet, you have to connect to it. Fortunately, you have a few options. Those options reflect the different technologies for connecting. Some technologies are just a bit beyond the budget of most residential users, while others are custom made for the small office/home office (SoHo) market.

You have two basic choices for connecting to the Internet:

Dial-up

A dedicated broadband connection (such as Digital Subscriber Line [DSL] or cable service)

Of those two options, the first one requires you to establish a connection each and every time you want to use the Internet. The other option is known as always-on or dedicated access. Your connection to the Internet is active as soon as you turn on your computer. Configuring a dedicated connection is much like configuring a connection to a TCP/IP network, which is what you see in Chapter 12, "Connecting to TCP/IP Networks." What you haven't yet seen is how to use a dial-up connection to get on a TCP/IP network.

It is quite tempting to just say that faster is always better when it comes to connecting to the Internet. As a general rule, that is true enough. However, there might be more to deciding how to connect to the Internet than you might have at first believed. The next section gives you inside scoop about some of the different access technologies and lets you see why smiling and dialing is still a popular pastime.