TCP/IP network explaining: At the outset and the first lesson

Content Introduction

1. Course Outline

2, the first part of the first lesson: Internet history

3, the first part of the second lesson trailer: the establishment of the Internet, OSI seven layer model

Course Outline

We will take you together to learn a lot of network skills, to introduce you to the basic knowledge of TCP/IP points. You will also learn how to build your own network and solve some of the problems you encounter on the Internet.

If you don't have any network foundation, it doesn't matter, this course is for everyone.

This will be a vast journey: Eagle hit the sky, Fish xiang shallow bottom, water frost days Freedom (Small series you can ...) ）

Our courses are divided into four major parts:

How to communicate on the local network

-History of the Internet

-Establishment of the Internet, OSI seven-layer model

-OSI First layer: Connect your machine

-OSI second layer: Make machines communicate with each other

-OSI second-tier devices: Switches

-Practice

Inter-network communication

-OSI Layer III

-Address range segmentation

-Routing

-Other protocols

Inter-application communication

-What is an app

-Enables the application to be connected

-Nat and Port mappings

-Review

Network Services

-DHCP Service

-DNS Service

-Web Services

-Practice: Building a small company network

Part One Lesson one: The history of the Internet

In the the 1950s, the communication approach was "point-to-point", meaning that only one machine could communicate with each other at a time. What about the network pioneers who wanted to communicate with several colleagues during the meeting? So they thought that if they could communicate with many people in real time, it would be much better to communicate with each other in sequence.

As a result, they designed a network of communication methods to replace the traditional centralized mode of communication.

Centralized communication network

This means that information can be passed between different nodes, even if some nodes disappear, without impeding the spread of information. In, we can see: through the network of communication forms, if a node out of the question, the information flow can go other paths.

Mesh Communication Network

Now that the idea is there, it will be realized.

But to make it easier, the pioneers of the network began by designing networks for the military. It was not until the the early 1960s that a preliminary document describing the Internet was compiled.

In the late 1960s, Arpanet (ARPA), the Senior Research Program (Advanced Studies Project Agency) of the United States, was the predecessor of the Internet. The ARPANET consists of only four machines. The network protocol used at that time did not allow ARPANET to achieve the desired target, because different communication technologies were used for machines from different networks.

As a result, the pioneers of the network racked their brains and finally devised a new universal network communication protocol, which is the great TCP/IP protocol (transmission Control PROTOCOL Protocol/Internet Protocol Internet Protocol). The internet continues to evolve, but until 1990 there was a major change: The invention of the HTML language and the creation of the HTTP protocol, the Web page was born!

With the advent of the first generation of browsers that display images and open domain names, the pace of Internet development has accelerated dramatically. We can see a remarkable leap in 1990-2000 years.

Today, there are 1.8 billion netizens and 200 million servers on the Internet.

The world's Internet users are unevenly distributed:

• 42% of Internet users come from Asia

• The countries with the highest proportion of Internet users are: South Korea

• 78% of Americans have internet, while in Africa only 10%

• One out of every 3 people in the world is on the Internet.

• The number of netizens in 2000-2010 turned 4, 5 times times.

• Internet in Africa grew by 2,360% in 2000-2010

Needless to mention, these figures are sufficient to demonstrate the importance of the Internet. Take a look at the following picture, which shows the interconnected machines on the Internet, pick up the magnifying glass and look at it carefully.

Of course, don't forget our primary purpose: to understand the workings of the Internet. So stop dreaming and do the right thing.

Part One: the creation of the Internet, the OSI seven-tier model

Today's class is here, the first class can not let everyone too tired, but from tomorrow onwards, we will formally learn the knowledge of TCP/IP and the Internet. Let's refuel together.

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TCP/IP network explaining: At the outset and the first lesson