What is ATM technology and what is its purpose?

Asychronous Transfer Mode (Asychronous Asynchronous Transfer Mode) is a kind of information transmission Mode that can transmit comprehensive business information at high speed, with high efficiency, flexible control, and novelty, it has been determined by the Telecommunications Standardization Department of the ITU-T International Telecommunication Union) as a delivery and exchange voice. Tools for images, data, and multimedia information have been widely valued and are one of the hot topics of information exchange today. The birth of ATM technology has its inevitability. With the arrival of the information society, people's demand for communication is far greater than that of traditional telephone and telegraph services, and the demand for data communication and broadband communication is growing, because of their different bandwidth and business needs, it is difficult to implement traditional communication methods. For example, existing networks are designed for a specific service and are often not applicable to other services: cable TV networks cannot transmit telephone services, while telecom networks cannot transmit TV signals. Obviously, these network technologies are insufficient to support new businesses. It is expected that only one network will exist in the future. It is independent of services and flexible, secure, economic, and effective use of all resources. ATM technology is regarded as a key technology for implementation.

The ATM system is a fast group exchange method that uses asynchronous time-division multiplexing technology. It divides information flows into fixed-length ATM cells and can easily achieve multimedia communication in which various information flows are mixed, it can dynamically allocate valid capacity according to service type and transmission rate, which is frequently used for high-speed metadata transmission and frequently used for low-speed metadata transmission. Therefore, ATM can adopt a single exchange mode to support a wide range of services, such as narrowband voice and data transmission to HDTV. An ATM Cell consists of a length of 53B, where SB is the header and 48B is the information domain. Therefore, the information transmitted online is all ATM cells. In order to complete the transfer of ATM cells, a typical ATM switch should have three basic parts: Line and outlet processing, ATM switching unit and ATM control. The ATM switching unit is the key, it transfers the online ATM cells to the desired outlets as required to complete the switching. The control unit controls the actions of the switching unit. The human line processing processes the input ATM cells to suit the requirements of the ATM switching unit. The outlet processing processes the cells sent by the switching unit, make it suitable for line transmission requirements.