Data transmission over a network includes a set of communication devices that are combined by data transmission channels, switched by devices and provide messaging between all end devices.
Between personal computers, for example, data transfer is irregular and is carried out according to the requests of people working on a PC. Devices can be silent for a long time, working autonomously (there is no data transfer at this time), and then send a message or document somewhere. With a low-speed telephone line, this file will be transferred for several minutes, and this often annoys users. To overcome these inconveniences, a network was developed that uses a common high-speed cable for all devices. We will not go into technical details here, but will only say that such a network can be represented as interconnected computers, each of which monitors the channel. In the case of transmission, computers recognize it by its address, and the one to which it is addressed receives the information. If necessarytransmission, a specific subscriber must wait until the channel is free, and then start transmission. If it happens that two users try to take the line at the same time, then after a short idle time, they try again until one of them is ahead of the other. A computer that occupies a shared channel can use it at full speed and in its entirety. This is a fairly efficient operation algorithm, in which data transfer is fast and reliable.
As you probably already guessed, the type of this network is called Ethernet. These types of communications are used in a small area, for example, inside one building. So it's a local kind of connection. The Ethernet network is internationally standardized and has captured almost the entire global market in its segment.
Radio-Ethernet is a very recent development. This is a new standard, and it has two applications. First, it is a wireless local area network within the walls of one building or on the territory 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.
The concept of "last mile" is used to determine the connectivity between the subscriber and the node closest to him in the "large network". This distance in reality can be from several meters to 20-30kilometers.
It is not advisable to bring a point-to-point radio channel to each subscriber, because in this case, for technological reasons, the channel will be expensive, and information will be pumped slowly. So it is much more efficient to arrange a point-to-many point channel and make it available to several subscribers. These subscribers can use it in collision mode, like an Ethernet local area network. This solution was invented and developed quite recently, and it is compatible with a conventional Ethernet cable. Radio-Ethernet has recently received the standard of the International Committee of the IEEE, and it provides technical stability in operational operation.
