What is the Internet and why has it been invented?
The Internet is a vast network that connects all the computers. While using the internet we can share information and communication throughout the world.
How does the internet work?
The Internet moves data from one place to another through the network in a series of hops. Data moves over the internet in a manner called packet switching. It works by using a packet routing network that follows Internet Protocol (IP) and Transport Control Protocol (TCP)
The origins of the internet are rooted in the USA in the 1980s. During the cold war between North America and the soviet union (Russia). People lived in fear of long rage surprise attacks due to deadly nuclear weapons. In that situation, the U.S needed a communications system that could not be affected by a soviet nuclear attack.
Computers were large &exclusively expensive machines used by military scientists and university staff in that period.
These machines were powerful but limited in numbers, researchers required access to the technology but had to travel a great distance. To solve this problem researchers started ‘time sharing’, i.e users could simultaneously access a mainframe through a series of terminals, although only a fraction of the computer’s actual power at their command. Overcome this problem led various scientists, and engineers to research the possibility of a large-scale network
For what purpose internet was invented?
Initially, the internet was invented for military purposes and then expanded for communication purposes. The first workable prototype of the Internet came in the late 1960s with the creation of ARPANET(Advanced Research Projects Agency Network). Originally funded by the U.S. Department of Defence, ARPANET used packet switching to allow multiple computers to communicate on a single network.
In 1965, Lawrence Roberts made two separate computers in different places ‘talk’ to each other for the first time. This experimental link used a telephone line with an acoustically coupled modem and transferred digital data using packets.
When the first packet-switching network was developed, Leonard Kleinrock was the first person to use it to send a message. He used a computer at UCLA to send a message to a computer at Stanford. Kleinrock tried to type ‘login’ but the system crashed after the letters ‘L’ and ‘O’ had appeared on the Stanford monitor. A second attempt proved successful and more messages were exchanged between the two sites.
How does the data transfer across the continent?
A larger amount of data is transferred thru Fiber optic cables at a very high speed. Compare to other cables, this cable transmits the data with a high bandwidth level, is less bulky, lighter, more flexible, and carries more data. There are 2 major types of fiber optic cables: single-mode and multi-mode. The single-mode fiber uses very thin glass strands and a laser to produce light. Multi-mode fiber optic cables use LED.
The single-optic fiber cable networks usually use Wave Division Multiplexing techniques to increment data traffic that each strand can carry. Wave Division Multiplexing allows combining light in multiple different wavelengths and then later separated. This effectively transmits multiple communication streams in a single light pulse.
Nowadays most of the internet traffic flows thru undersea cables. These cables – often thousands of miles in length – are able to transmit huge amounts of data rapidly from one point to another.
A submarine cable is a fiber optic cable laid in the ocean, connecting two or more landing points. The cables are laid using ships that are modified specifically for this purpose, transporting and slowly laying the ‘wet plant’ infrastructure on the seabed. These special ships can carry thousands of kilometers of optical cable out to sea.
Some traditional method of laying optical fiber still used in most developing countries is Ducting and Trenching. This involves creating a trench through manual or mechanized soil excavation. This approach is preferred in countries where manual labor is cheap. There are around 380 underwater cables in operation around the world, spanning a length of over 1.2 million km(745,645 miles).