untangling_the_web

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Researching & Understanding the Internet
A Plain English Guide to Internetworking
The Internet, were it a person, would be something of a narcissist. It probably has
more information about itself than any other single topic, which means the best place
to research the Internet is the Internet. However, understanding how the Internet
actually works can be frustrating and most books, websites, and other resources that
purport to explain the inner working of the Internet exacerbate rather than enhance
knowledge because they make assumptions about their readers that are often wildly
inaccurate.
There are generally two types of guides on how the Internet works: one is the
technical guide for network engineers and system administrators; the other type is a
users' guide, a how-to book for people who want to use the Internet but don't really
need to know anything about what's under the hood. The first type of guide is fine if
you are an engineer, but these manuals or websites are written by and for technical
people, meaning you already have to know their jargon in order to understand what
they are saying . The second type of guide merely avoids the problem all together by
ignoring technical explanations. After all, you don't need to know how an internal
combustion engine works to drive a car.
I have attempted to create a little niche in between the extremes by offering a nontechnical
explanation of some of the basic concepts behind how the Internet gets
traffic from one point to another and does it with remarkable speed, accuracy, and
efficiency. For many of us who are not technically inclined, the answer has often
seemed to be "magic happens here." But more and more often in our jobs we find
we need to know a little bit about the mysterious inner workings of the Internet. I
have no pretensions that this overview is complete. I knowingly gloss over some
subtleties that I think are simply too arcane for a high-level look at Internetworking.
The Internet
The Internet isn't a single network; it is a network of networks . However, all these
many networks are not directly connected to each other and, in fact, do not "talk" or
exchange data directly with each other. Rather, the Internet employs an elaborate
system of rules (known as protocols) , numbering schemes (e.g., autonomous
systems, IP addresses), hardware (e.g., routers and servers), and arrangements
(e.g., peering agreements) to ensure that your request to view a website in Pakistan
or send an email to Seoul is fulfilled almost in the blink of an eye.
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