known that one of the most significant achievements of humanity in the past century has been the creation and rapid development of information technologies - technologies to using computers and various types of computer networks, store, process, convert and transfer large amounts of information.It is worth noting that such a rapid leap Information humanity became possible only after the computer had been set up communication networks.
All types of computer networks are a collection of computers distributed over a certain territory and linked by specialized channels that can transmit data.Today, computer networks have been widely spread, various kinds of computer networks around the world operate and interact with each other.Current understanding of networking features, has led to the classification on a territorial basis.According to this classification includes such types of computer networks:
Global Area Network (GAN) - the global network that combine computers and networks located in different
Wide Area Network (WAN) - large-scale networks of a computer network at the level of continents and countries;
Metropolitan Area Network (MAN) - long distance networks of computers and networks within the regions and other administrative units;
Local Area Network (LAN) - LANs imply association of computers located at a relatively short distance - for instance, within the same building.
WAN and MAN networks are regional.It should be noted that to date the separation of computer networks in the WAN and MAN Group is very conditional, because now almost every part of the regional network of any WAN.
many organizations that are interested in maintaining a high level of information protection from attacks from the outside (for example, military, banks, etc.), create their own networks, known as corporate.In a corporate network may include tens of thousands of computers that are located at a considerable distance from each other, for example, in different countries.
most common in the world numerically are local computer networks.
main feature of LAN is the ability to connect computer cable, without the need for channels for transmission of data used by global networks (telephone network, fiber optic cable, airwaves and so forth.).Since the computers are located close to each other, to create a network cable is sufficient to connect them, and adjust accordingly.Network integration of computers in the internal production area network gives its holder a lot of advantages.
Types of local computer networks often share a topology - a method of connecting computers to each other.Topology is a major feature of Ethernet as the connection method is determined by the most important figures presented performance and reliability of operation.
biggest advantage of the network have performed according to the topology of "star" - to one central source connected to all the other computers on the network.
existing networks formed according to the topology of the "ring" - all of the computers communicate with each other in sequence and eventually form something resembling a ring.
third type of topology, for which a local computer network, a bus topology - all the computers on the network are connected to a single cable - data bus.
Computer networks, how they work, protocols, and hardware components are constantly being improved and developed.