Overview

Asynchronous Transfer Mode (ATM) is a technology based on packet transmission mode, and it also incorporates the high speed of circuit transmission mode. Due to its flexibility and support for multimedia services, ATM is regarded as a core broadband technology.

As defined by the ITU-T, data is encapsulated in cells in ATM. Each ATM cell is 53 bytes in length, of which the first 5 bytes contain cell header information and the last 48 bytes contain payload. The major function of the cell header is to identify virtual connection. In addition, it can be used to carry limited flow control, congestion control, and error control information.