The Internet is based on the TCP/IP network protocol, which actually consists of two network protocols: TCP and IP. The TCP protocol manages the process of transmitting information. The protocol is IP – addressable, it determines where the information is transmitted. The TCP/IP protocol controls the transfer of data between computers on the network. This happens as follows. The data is divided into small packets, each with its own number. Information necessary for its transmission is added to each packet: the address of the sending computer, the address of the receiving computer, etc. Then the packets are forwarded, and they can go by different routes (those that are currently free).
Special computers-routers (from the English Router) determine the path along which a particular packet should be sent from one computer to another. After the package is delivered to the recipient computer, the integrity of the package is checked. Before sending each package, so-called checksums are added, which are calculated according to the package data. After delivery, the checksums are calculated anew, and if they coincide with the initial ones, the package is delivered without damage. If a package is damaged or has not been delivered at all, the receiving computer requires resending the package.
It is almost impossible to organize access to all the features and services of the Internet using a home computer: for this you need to have special hardware and software. Therefore, for the organization of Internet access, as a rule, the "client-server" technology is used.
For the functioning of a server program that provides Internet access and serves clients, you need a sufficiently powerful computer (often even several). The organization of servers and the supply of Internet services are handled by special organizations – Internet service providers.
For an ordinary user to connect to the Internet, it is necessary to conclude an agreement with the provider organization and physically connect to it. Connection to the provider can be carried out by one of the methods given in the previous paragraph (for example, by remote connection).
The provider assigns its own IP address to the computer and performs the role of a server for it. In order to use Internet services, in addition to programs that support the TCP/IP protocol, programs that support application protocols must be installed on the client computer. Each Internet service has its own application protocol, for example, a mail protocol, an FTP file transfer protocol, etc. So, an email client is installed on the computer to use e–mail, an FTP client is installed for file transfer, and so on. toponlinecasino.pl
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