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Asynchronous Transfer Mode

(also ATM)

ATM definition

Asynchronous Transfer Mode (ATM) is a switching technology used in telecommunications networks for data, voice, and video transfer at high speeds. ATM has been largely replaced by newer technologies, but it may still be used in certain niche cases (like high-speed trading in the financial industry) and legacy systems.

See also: network frame, virtual switch, digital switch

What does ATM use for data transmission?

To transmit data over the network, ATM uses fixed-length frames called “cells.” ATM cells are 53 bytes in size, with a 5-byte header (destination address, priority, and other control information) and a 48-byte payload (the data being transmitted).

How does ATM data transmission work?

ATM uses virtual circuits (logical connections that allow for the efficient allocation of bandwidth) to manage the flow of data between devices. There are two types of virtual circuits in ATM: pre-established permanent virtual circuits (PVCs) and dynamically generated switched virtual circuits (SVCs).

When a virtual circuit is established, a path is defined through the network for the transmission of data. The ATM cells are transmitted individually over the virtual circuit in a process called “cell switching.” Each ATM switch examines the header of the cell and uses this information to forward it to the appropriate destination.

ATM also uses a quality of service mechanism to prioritize different types of traffic, allocating more bandwidth to high-priority data (such as voice and video feeds).