(LAN) technology has not yet appeared. Up to now, the Internet has been running at least 1600 for nearly 30 years.
Ten thousand mainframe.
Now we are accessing the largest network in the world every day, communicating with friends, peers and each other through the network.
How much do we know about this network when we get news and information online? Do we have time and mood?
In the fast-paced modern life, take some time to think about the significance of the Internet?
I often ask myself: What is the Internet? What does the Internet mean? What is the essence of the Internet? why
Will the Internet develop as it does today?
Definition of technical expert
There is no doubt that the Internet is the product of modern high-tech. When we try to understand the nature of the internet, there are
First of all, we should understand the definition of technical experts.
1995101October 24th, "FNC: Federal Network Council".
A resolution on the definition of Internet was adopted:
"The Joint Network Committee believes that the following language reflects our definition of the word' Internet'.
Internet' refers to a global information system-1. It is logically linked by a globally unique address.
The address is based on Internet Protocol (IP) or other future protocols.
2. Transmission control protocol and Internet protocol (TCP/IP) can be adopted, or other subsequent protocols in the future.
Or a protocol compatible with Internet Protocol (IP).
3. You can let public users or private users use advanced services. This service is based on the above communication and correlation.
Above the infrastructure. "
Of course, this defines the internet from a technical point of view. This definition reveals at least three aspects to us: first,
First, the Internet is global; Secondly, every host on the Internet needs to have an "address"; Finally, these hosts
They must be connected according to the same rules (protocols).
The Internet is global. This means that the network we are currently using, no matter who invented it, belongs to.
Of all mankind. This "globality" is not an empty political slogan, but has its technical guarantee. Just as we are in
As we have seen in the second chapter of this book, the structure of the Internet is a distributed network connected by "packet switching".
Collateral Therefore, on the technical level, there is absolutely no central control problem on the Internet. In other words, there can't be anyone.
The problem that a country or an interest group controls the Internet through some technical means. On the other hand, it is impossible to put each other
The Internet is closed in a country-unless it is not the Internet.
At the same time, however, such a global network must have some way to determine each station connected to it.
Host. On the internet, it is absolutely impossible for two people to have the same name. In this way, it is necessary to have a fixed organization.
Each host determines its name, thus determining its "address" on the Internet. However, this is just "naming"
Yes, the power to decide the address is not equal to the power to control. Except for naming, the organization responsible for naming cannot
Do more.
Similarly, this global network also needs an organization to formulate communication rules that all hosts must abide by.
Otherwise, it is impossible to build an Internet that can be used by all different computers and different operating systems in the world. under
The first generation TCP/IP protocol will classify the information levels on the network to speed up the transmission (for example, priority transmission and browsing).
An example of the service provided by this organization is information, not email information. Similarly, this formulation is the same as compliance.
The power of "consent" is not equal to the power of control.
Undoubtedly, all these technical features of the Internet show that the management of the Internet is completely related to "service".
Off, has nothing to do with "control".
In fact, the current Internet is far from the "information superhighway" that we often say. This is not only because at present
Internet transmission speed is not enough. More importantly, the Internet has not been stereotyped, and it has been developing and changing. Therefore, any
The technical definition of the Internet can only be present and current.
At the same time, as more and more people join the Internet and more and more people use the Internet, they will not
This paper puts forward a new understanding of the significance, value and essence of the Internet from the perspective of social culture.
The network is the media.
As we have seen before, the emergence of the Internet is of course a revolution in human communication technology, but if
It is obviously not enough to understand the meaning of the Internet only from a technical point of view. The development of the Internet has already surpassed the original.
The military and technical purpose of ARPANET is to serve human communication almost from the beginning.
Even in the early days of ARPANET, the Command and Control Research Office of the Defense Advanced Research Projects Agency (DARPA)
Rick Riddle, director of the Computer Research Center, stressed that the basic function of computers and computer networks is to serve people's communication, rather than
It is only used for calculation.
Later, DavidClark, a senior researcher in the Computer Science Laboratory of MIT, also wrote:
"It is wrong to regard the network as a connection between computers. On the contrary, the Internet connects people who use computers. mutually
The greatest achievement of networking lies not in the technical level, but in its influence on people. E-mail may not be suitable for computer science.
However, important progress is a brand-new way for people to communicate. The continuous development of the Internet has brought us great benefits.
Everyone is a technical challenge, but we can never forget where we came from and what we gave.
The great changes brought by the large computer community cannot forget our potential for future changes. "(RFC:No..
1336)
Obviously, judging from the development process of the Internet so far, the network is communication.
The English word "Communication" is not easy to translate. When we talk about news, news, this
Words refer to communication and exchange; When we talk about traffic, the word refers to traffic; When we discuss interpersonal relationships,
Sometimes, this word is related to communication and communication. At that time, Licklidel emphasized that the role of computers was "communication", that is,
That's the word.
Interestingly, "computer" and "communication" are the same word.
Root: "com" (* * *, all, combination, etc.). The old English word "communication" means "participation".
In American universities, people usually study mass communication instead of journalism. in this
In a sense, "communication" has nothing to do with propaganda and being publicized, but is closely related to the "communication" in which everyone "participates".
Related. I emphasize here that "the Internet is the media" and also to emphasize the important role of the Internet in human communication and exchange.
Use.
The development of the Internet has fully proved the media characteristics of the network. On the one hand, as a narrow range.
Private media, the Internet is an excellent tool for private communication. On the Internet, e-mail is always made.
One of the most widely used and valuable functions. Due to the emergence of e-mail, communication between people is more convenient and common.
All over.
On the other hand, the Internet is widely used as a wide, broad, open and effective media for most people.
A large number of websites are visited by at least thousands or even hundreds of thousands of people every day, realizing the real role of mass media. internet
It can spread an idea or information faster, more economically, more intuitively and more effectively than any other way.
The emergence of Internet, e-mail and the use of World Wide Web provide good tools for people's communication.
Web pages are publications.
If it is understood as "the network is the media", it is easy to understand the web pages of the World Wide Web as one of the functions of the Internet.
In essence, it is a kind of publication, which has almost all the functions that a printed publication should have. The fact that the World Wide Web has developed in recent years,
Proved this.
In fact, quite a few users of the World Wide Web directly regard the World Wide Web as a publication. According to NetSmart's statistics,
50% users read online magazines and 48% users read online newspapers. net/statsl.htm)。
Even if you don't read newspapers and periodicals through the World Wide Web, the pages of the World Wide Web themselves play the role of publications.
Burnsley, the inventor of the World Wide Web, in his manifesto on the World Wide Web
(.net/stats 1.htm)
As such a media with both private and public functions, the realization of Internet utility is fundamentally dependent.
The increase of participants, that is, users. This feature is completely in line with the nature of the network.
The bigger the better.
When the information industry is unpredictable because of the fast pace and great changes in the market, it begins to believe in the principle of "turning around when the boat is small"
Sometimes, the network follows the creed of "bigger is better".
Indeed, if there is only one computer, there is no point in installing a network card. However, as long as there are two sets of electricity
Brain, and two computers can share data with each other, so both computers are alive.
Because every computer can use the data of another computer, every computer has two computers.
Brain data.
We can further imagine that there are 10 computers connected to the Internet. If not connected to the Internet, its function is 10 computers. but
Yes, if these 10 computers are networked and can share data with each other, then each computer can receive it in essence.
The effect of "one is ten". Therefore, in this sense, for computer networks, every additional computer is not.
Simply add one by arithmetic. In the above example. A computer is a computer and two computers connected to the Internet.
Since each computer is equivalent to the contents of two computers, it is relatively equal to four computers. If the networked 10
If each computer "takes one as ten", it is relatively equivalent to 100 computers.
It is in this sense that BobMetcalfe, who formulated the Ethernet standard, put forward the famous.
Metcalfe's law: the value of the network increases geometrically with the increase of the number of network users. That is, using the
The more users, the greater the value of the network.
When we use computers to process official documents in the office, we use computers to write, play games, watch VCD or manage the family at home.
Politics (if necessary) may not have thought that this is a great waste of computer resources. At first, this computer
You can have the resources of thousands of computers-just by networking.
So the essence of computer is networking, and the essence of network is that the bigger the better. Networked computers are nothing like women.
Elegance is just a fashionable behavior, but let the computer exist according to its nature. Computers without internet access will never
Check the computer.
Fortunately, the Internet is such an international network that computers can be connected together to the greatest extent.
The fundamental reason why collateral can realize such a real large-scale network lies in the openness of the Internet.
Make love.
Openness is the way out.
The history of China has proved that there is no way out of the country; For networks, turn off
There will be no way out.
What kind of information infrastructure should be established in the United States (NII: National Information)?
Infrastructure has always been a controversial issue. Networks that have worked well for years, such as AOL.
OnLine) "and" CompuServe "are obviously closed systems.
In such a closed network where no one can enter, everyone who joins the network is given a certain number.
Permission Every webmaster's activities in the network may be strictly managed.
However, with the popularity of the Internet, the significance of this closed network has been greatly challenged. The root cause lies in sealing.
A closed network essentially violates the openness of the network. As we emphasized before, the computer's
Nature needs networking. The bigger the network, the more it can play the role of computers.
At present, in practice, the closed network is increasingly challenged by the open Internet. any
The network must provide sufficient and effective information services. A network that only provides information services in a single domain often means users.
Only users related to this field can join the network. Anyone who builds a "big and comprehensive" network
Network work is often limited by the ability of information providers.
In addition, both enterprises that provide "big and comprehensive" information and users who enjoy "big and comprehensive" information must
Pay the economic price for such a "big and comprehensive" information-after all, maintain such a closed and "big and comprehensive" information.
The cost of the network is too high.
Because of this, "AOL" and "computer services" must eventually be open to the Internet.
In order to connect to the Internet, at least we must provide the same Internet access service as other Internet service providers (ISPs).
Service. This also means that the closed services of these networks themselves are reduced.
Therefore, with the development of the Internet in the past two years, it has become an indisputable fact that an open network must be established.
Understanding the Future of Information Interconnection edited by National Research Council
Network and others "(realizing the information future-Internet and)
National Academy Press, Washington, DC, zip code: 1994 .P43), discusses "open data network" in detail.
(OpenDataNetwork)”。 The book emphasizes that the National Information Infrastructure (NII) in the United States must be built.
Standing on the open data network. The so-called "open network" means that "all kinds of information services can be developed,
(This information) can come from various types of providers, can be used by various types of users, and can go through various types.
Network service organization, and this connection should be smooth. "
Specifically, this openness is reflected in four aspects:
"1. Open to users. Do not force users to enter a closed system, or force users not to connect to other systems.
Let's go But allows a wide range of connections. Just like the telephone system.
2. Open to service providers. It can provide an open and accessible ring for business or academic needs.
Conditions.
3. Open to network providers. In this way, anyone who provides the network can become a part of the whole Internet.
4. Be open to future improvement. You can add new services in the future, not just one service. "
As an open system, each local and independent network can be designed according to its own needs.
You can have your own interface, your own user environment, and follow the TCPIP protocol when surfing the Internet.
All right.
This open network structure was first proposed by Kahn around 1972, that is, during that time, he was in Washington.
Successfully led the earliest ARPANET demonstration. V.Cerf and Kahn*** are the same TCP/IP protocol.
An open example. This agreement is not designed for a certain purpose, but for everyone.
"A Brief History of the Internet" (-
History/), but also repeatedly stressed the openness of the Internet. This paper holds that:
"The key concept of the Internet is that it is not designed for a certain demand, but an ability to accept any new demand.
General infrastructure of the solution. "
Therefore, the Internet is an open network. The symbol of the Internet is not only the use of routers, but also the ability.
Access the Internet through TCP/IP, and more importantly, only an open network is the Internet.
At present, our "Internet" has only four external channels, which is said to facilitate "management".
But as far as foreign banks are concerned, it is doubtful whether they can really be managed through restricted channels. However, first,
This kind of "management" will make the already crowded network more crowded. Moreover, if this "management" can be established.
If it is, it must be two-way. As we talked about in the first part of this book, the Internet initially
The design idea is not central control, and the damage of any part of the network cannot destroy the whole network. But in today's China,
The situation of the "Internet" is that these four exits are stuck and the whole "Internet" is paralyzed.
The most incredible thing is that China's "Internet" is not interconnected! For example, it is also in
Beijing, from ChinaNet of the Ministry of Posts and Telecommunications, has access to campus networks such as Peking University and Tsinghua, and even takes a trip to the United States!
So in many cases, even for users in China, it is likely that visiting an American web page is more important than visiting it.
Web pages in China are easier and faster. This makes the Internet in China more similar to the original Internet.
Go away.
Broadband network is called "broadband network" or "broadband" for short in Hong Kong and Taiwan.
We know that although the speed of dial-up Internet access has increased from 14.4Kbps to 56Kbps in just a few years, due to the quality of telephone lines, 56Kbps should be the limit of general modems. In order to get faster internet access, it is necessary to split the stream path, so in recent years, various broadband access services have emerged one after another.
So, what is broadband? There is actually no strict definition. Generally, the current dial-up Internet access rate is limited to 56Kbps, and access below 56Kbps is called "narrowband", while access above 56 kbps is classified as "broadband".
This website introduces broadband technology in detail >>
Some people can't help asking: What about ISDN? Is ISDN broadband? Of course not. However, because it can provide much faster access service than ordinary modem dial-up internet access and has a certain number of users, it is necessary to know about "the earliest broadband-ISDN".
Optical thousand is essentially similar to broadband, and the network speed is much faster than broadband.