To replay your query “When was the Internet Invented?” let us present the story behind Internet History. Internet started as a project of US department of defense. The Technical group then created was known as Defense Advance Research Projects Administration (DARPA). Its goal was to create a way for widely separated computers to transfer information and data and to make this data communications as much reliable as possible.
DARPA required to make a network that was smart enough to recover on its own from problems such as power failure interruption in communication lines even in nuclear attacks. DARPA called its network as DARPA net. Eventually the government dropped the idea that its network was only useful for defense related projects and the network became known as ARPA net. Around this time the government also started connecting many of the country’s universities to the network. Since then, generations of students have studied, used and improved what is today known as Internet. ARPA net is generally considered as the first version of internet.
The ARPANET (Advanced Research Projects Agency Network) built by DARPA of the United States Department of Defense, was the world’s first operational network. It is generally called as the predecessor of internet. The first ARPANET link was set up on November 21, 1969. It was established in UCLA (University Of California, Los Angeles) for the interconnection of four Universities. The first message sent over this network was on October 29, 1969 at 10:30 PM.
There were four nodes in the network each representing one university. Node is actually a machine in the network. The four nodes are:
- University of UTAH
- UCLA (University of California, Los Angeles)
- UCSB (University of California, Santa Barbara)
- SRI (Stanford Research Institute)
In October 1972 ARPANET went ‘public’. In the First International Conference on Computers and Communication which was held in Washington DC, the system in operation was demonstrated by ARPA scientists by connecting computers together from 40 different locations which inspired the Western world to research further in science. Other networks appeared soon after this. The Washington conference also established an Inter-networking Working Group (IWG) to organize the research taking place. Meanwhile ARPA scientists were occupied on enhancing the system and expanding its capabilities.
- In 1972, they successfully made use of a new program which is now referred to as e-mail, that would allow to send the messages over the net, allowing direct person-to-person communication.
- The new host-to-host protocols developed in the early 70s allowed access to the hosts’ programs. Before then the system only allowed a ‘remote terminal’ to access the files of each separate host.
- A common language called TCP/IP ( Transmission Control Protocol/Internet Protocol) was developed by ARPA scientist in 1974 with help from experts in Stanford which would allow communication between different networks.
The development of TCP/IP marked a key stage in networking development. In 1982, ARPANET allowed TCP/IP for its functioning. This is known as the birth of internet. During the initial stages internet was only used for transferring files between computers. A protocol (rule) known as FTP is used for this purpose. FTP stands for file transfer protocol. Then a language known as GOPHER is introduced by the University of Minnesota. It was helpful in increasing the contents of internet. GOPHER can be used to create web pages in the internet. But it has some drawbacks. It does not support multimedia content. So a new technology was introduced for writing web pages, known as Hyper Text Markup Language. After the introduction of HTML, internet became very powerful. HTML allows the web pages to contain videos, sound clips, animations and so on.
So the Internet History can be divided into 3 stages:
- Initial stage: internet is generally used for file transfer purposes based on FTP protocol.
- Second stage: GOPHER was introduced. Web pages contained text only.
- Third stage: HTML was introduced. Multimedia features were introduced in web pages.
From there on, internet has grown very rapidly. Internet is now a global network of networks. It actually consists of many networks. The number of computers in such a network can range from two or three in a small intranet to several thousands in large organizations.
How Internet Works?
Internet is a network of networks. Each network will contain several computers. Each machine in the network is known as a host. It will have a unique address known as internet address (generally known as IP address). IP address is a 32 bit address. It will be in the form of aaa.bbb.ccc.ddd.
One network is connected to another network using certain devices known as routers. Information is sent from one machine to other in the form of packets. Each packet will have a header( which contains address of the machine to which the packets are sent) and a body. So router checks the header of the packet and sends the information to the specified machine.
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