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麻烦帮写一篇英语作文 题目是how does the world wide web work?

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麻烦帮写一篇英语作文 题目是how does the world wide web work?
麻烦帮写一篇英语作文 题目是how does the world wide web work?
world wide web 就是万维网呀
4. How Does the Internet Work?
While it is not necessary to understand how the Internet works in
order to use it, a brief technical overview will introduce you to
some concepts and terms that will be used in the sections ahead.
As we go into more detail here, we are assuming that you, the reader,
have at least a passing familiarity with computers. Section 6.2
provides more information on computer hardware and software.
On one level, networks are built out of wires, phone lines, and other
pieces of hardware, and the Internet is indeed built of all these
things. The essence of the Internet however is built out of an idea
called the Internet Protocol.
There are many different kinds of computers. Most of them work by
encoding information into ones and zeroes, which they can manipulate
at incredible speeds. Unfortunately, there are many different ways
of encoding information. Computers that use different methods can be
said to speak different languages. In order for computers to talk to
each other there must be a thing called a "Communication Protocol"
that provides a set of procedures for talking and a common language
to use.
The Internet Protocol, or IP, is the Communication Protocol that all
computers on the Internet must use and understand. It allows
computers to find each other, and to send packages, or "packets", of
information back and forth. Much like the Postal service reads your
country code, city code, etc., but not the contents of your letter,
the Internet Protocol does not care what is inside most of these
packets of information. This is a great thing because it means that
other, higher level protocols may transmit any possible kind of
information simply by stuffing it into a packet and handing it off to
the software responsible for speaking IP.
Another important protocol upon which the Internet is built is the
Transmission Control Protocol, or TCP. IP by itself provides a way
of sending a message to another computer, but no guarantee that it
will get through. Since reliable communication is a necessity, the
TCP protocol was invented which uses IP to send packets and
guarantees their delivery by requiring the receiver to acknowledge
the information received. TCP and IP form the heart of a group of
protocols aptly named the TCP/IP protocol suite. This suite of
protocols provides most of the functionality of the Internet.
We will be mentioning these protocols throughout the rest of the
document. Information on IP and other Internet Protocols can be
obtained through the resources referenced in Section 10.
4.1 Internet Addresses
There are many things we would like to be able to find on the net,
including people, information, and the computers themselves. An
important part of IP and other protocols is the way they label things
so that the computers can find and identify them. The U.S. Post
Office finds people by their Postal Address, which is just a label
containing information about who you are, and where you live.
Likewise, the various protocols of the Internet have given computers,
people, and information, addresses which can be used to find them.
The following sections will describe several different kinds of