Data transmission over the network includesa plurality of communication devices that are combined by data channels are switched by devices and provide messaging between all end devices.
Between personal computers, for example,the data transmission is irregular and is carried out according to the requests of people working for the PC. Devices can remain silent for a long time, working autonomously (data transmission is not carried out at this time), and then send somewhere a message or document. With a low-speed telephone channel, this file will be transmitted for several minutes, and this often causes irritation among users. To eliminate such inconveniences, a network was developed in which a common high-speed cable is used for all devices. We will not touch on the technical details here, but let's just say that such a network can be represented in the form of interconnected computers, each of which monitors the channel. In the case of transfer, computers recognize it at the address, and the one to which it is addressed receives information. If it is necessary to transfer a particular subscriber must wait for the release of the channel, and then start the transfer. If it happens that two users try to occupy a line at the same time, after a short time they try again for a short time, until one of them overtakes the other. You can use the computer that has shared the channel at full speed and in full. This is a fairly efficient algorithm of operation, in which data transmission is fast and reliable.
As you probably already guessed, the type of this networkis called Ethernet. These types of communications are applied in a small area, for example, within a single building. So this is a local type of connection. The Ethernet network is standardized at the international level and has occupied almost the entire world market in its segment.
Radio-Ethernet was developed quite recently.This is a new standard, and it has two uses. First, it is a wireless local area network within the walls of a single building or on the premises of an enterprise. It solves the problem of "limited mobility" within the organization - all employees have high-quality access to the network. Secondly, Radio-Ethernet allows you to solve the problem of connecting to a large network of subscribers, while the transfer of personal data is carried out bypassing the problem of the last mile.
It is inappropriate to bring to each subscriberradio channel "point-to-point", because in this case for technological reasons the channel will be expensive, and the information will be pumped slowly. So it is much more efficient to arrange a point-to-multipoint channel and to place it at the disposal of several subscribers. These subscribers can use it in a collision mode, like a local Ethernet network. This solution was invented and developed quite recently, and it is compatible with a conventional Ethernet cable. Radio-Ethernet recently received the standard of the IEEE International Committee, and it provides technical stability in operational work.
