In modern conditions, the activities of society and civilization are impossible without the use of means of rapid exchange of information. This problem is designed to solve global computer networks.
A global computer network (GKS) is a network that consists of computers covering vast territories with an unlimited number of computer systems included in this network. The main condition for the functioning of such networks is the instant transmission of information over the network, regardless of the distance of the transmitting and receiving computers.
The global network differs from the local one, firstly, in lower data transfer rates. Global networks operate via TCP / IP, MPLS, ATM and some others. The most famous of these is the TCP / IP protocol, which includes subprotocols of different levels: application, transport, network, physical and channel.
At the application level, most programs work that have their own protocols that are widely known to ordinary PC users (HTTP, WWW, FTP, etc.). These protocols provide visualization and display of information required by the user.
The transport protocol is responsible for delivering the data to the exact application that can handle it. It is called TCP.
The network layer is, in fact, the receiver when transmitting information and sending requests to lower layers to receive all the information. Bears the name of the IP protocol.
The physical and link layers are responsible for defining the conditions and methods of information transfer.
The most famous global network is WWW (World Wide Web), which is a collection of servers that store information necessary for users and computers that can both receive information from servers and download it to them. WWW is characterized by convenience and ease of use, as well as low requirements for data transfer speed. This allowed the development of this network over a period of slightly more than a decade.
