What Is an ATM Surcharge?

People are generally used to divide telecommunication networks into transmission, multiplexing, switching, and terminals. However, with the development of program-controlled time-division switching and time-division multiplexing, the three parts of transmission, multiplexing, and switching in telecommunications networks have become more and more closely linked, and they have been uniformly described using transfermode. At present, the transmission methods on the communication network can be divided into two types: synchronous transmission method (STM) and asynchronous transmission method (ATM). For example, 2B + D on the ISDN subscriber line, and the digital multiplexing level in the digital telephone network are all synchronous transmission methods. Its characteristics are that in the time-division multiplexed signal composed of N original signals, each original signal is It appears periodically at a certain time interval, so as long as you can determine which way the original signal is based on time. However, each original signal of the asynchronous transmission method does not necessarily appear periodically at a certain time interval, so it is necessary to add another flag to indicate to which original signal a certain piece of information belongs. For example, a logo that uses a letterhead before a cell is an asynchronous transfer method. The letterhead of ATM cells in broadband ISDN is an example.

ATM protocol

The ATM protocol consists of the relevant ATM layers required for communication. ATM can be logically described in three levels:

User plane-is the interface between user protocols such as IP or SMDS and ATM.

Management planeCoordinates the various layers of the ATM stack.

Control Plane-Coordinates signalling and the creation and removal of virtual circuits.

The combined technology is mainly divided into two categories of overlapping technology and integrated technology. When overlapping technology is used, the endpoint uses both the address and the address or address to identify the server in the network. The address mapping function of the address and address or address is established. After the end user obtains the address of the end user, a connection is established and data packets are transmitted on it. The typical technology in this area has the advantages of overlapping technologies, such as the use of standard forums or signaling standards that are compatible with standard networks and services. The disadvantage is that the efficiency of packet transmission is low. When using integrated technology, the peers of the layer are regarded as the peer endpoints of the layer only need to use the address to identify the use of non-standard signaling protocols when establishing the connection. The use of integrated technology does not require an address resolution protocol but adds complexity to the switch to make it look more like a multi-protocol router. Typical technologies in this area are integrated technologies such as switching and multi-protocol label switching. The advantage is that the efficiency of transmitting packets is relatively high. Address resolution protocols are not required. The disadvantage is that it is difficult to integrate with standard technologies. Through research on various and combined technologies in the past two years, it has been concluded that overlapping technologies such as,, etc. are more suitable for private networks or small-scale networks, while integrated technologies such as switching, etc. are more suitable for large-scale public networks. The proposal to transmit information on the public network has been adopted in the year. The proposal clarified that the recommended technical solution for transmitting information on public networks using technology, including service provision networks and bearer networks, is multi-protocol label switching and clearly public. The target services supported by the network are differential services, integration services, and virtual private networks.