How does a Tower Crane Work

What is Internet:

The Internet is a worldwide network of millions of computers connected to each other by wires, optical cables or radio waves.  The connection between the devices allows users to communicate or share information and resources with each other.  Smooth and efficient data transmission is ensured by well-established rules and protocols.  Data is transmitted to short distances through wireless connections, while in the case of larger distances; transmission takes place through electric or optical cables. 

What is Internet

How does a Computer Network Work:

Data centers located on different continents are connected to each other by optical cables laid on the ocean floor.  Currently, there are more than 400 Internet cables laid on the floor of oceans and seas, and their number is continuously changing as new ones are installed and old ones are removed.

Computer Network

According to estimates, the total length of underwater Internet cables is about 1.3 million kilometres.  There are relatively short cables, for example the one that connects Ireland and the United Kingdom measuring 131 kilometres in length as well as very long ones, like the cable providing connection between Asia and the USA, which measures 20,000 kilometres in length.

underwater Internet cables

The signal must be amplified at intervals of 80-100 km to avoid data loss.  About 99% of the Internet traffic between continents takes place through these cables.  Contrary to popular belief, the Internet is not an intangible notion, but a set of interacting devices and the systems guaranteeing the connection between them. 

When you upload something to the cloud, the information is stored using the resources of the service provider's data centre.  Even though the cloud seems to be a virtual storage system, data is actually stored physically in it.  The first version of the Internet was called ARPANET that connected the computers of four American universities' campuses (University of Utah, University of California-Santa Barbara, University of California Los Angeles and University of Stanford).  The first message through ARPANET was sent on October 29, 1969 from the University of California to the University of Stanford.

Digital data transmission and storage:

Digital data transmission and storage, be it texts, images or videos, use a binary number system where numbers are represented by two digits, 0 and 1. These number sequences are transmitted as light and electric impulses or radio waves.  For effective data transmission, large files of messages and information must be divided into smaller units, called network packets. 

Digital data transmission and storage

Any available route can be used to deliver these packets to their destination, where they are reassembled.  As opposed to traditional voice communication, this method does not require a single dedicated route between each pair of users.  Besides the instructions on how to assemble them, each packet contains information about the sender and the recipient.  Routers function as data traffic controllers. 

Routers function

Their task is to find the fastest route for each packet. If a route is congested, the router forwards the packet through another route.  Usually, network packets arrive at the destination through various routes.  It is also possible that they do not reach the recipient in the same order in which they were sent.  When every packet has arrived, the receiving computer assembles the message.

How does a computer network work

Local area networks (LAN):

Local area networks (LAN) connect the computers within a given location, like an office, a school or a hospital, while wide area networks (WAN) provide a connection between devices located at larger distances from each other, for example in different cities.  countries and continents.  Thanks to its structure, the network of Internet connections can be extended easily without interrupting the service. 

Local area networks

Networks follow protocols to standardize communication between each element.  Every computer connected to the Internet must have a unique identification number (numerical sequence), called Internet Protocol address (commonly known as IP address), so they can be identified by other devices.  Computers can also establish a connection between each other via switches and routers.  Switches serve mainly to connect computers within a network, while routers are usually used for connecting several networks.