Overview of ATM

Introducing ATM

Asynchronous Transfer Mode is a network technology that combines the features of cell-switching and multiplexing to offer reliable and efficient network services. ATM provides an interface between devices such as workstations and routers, and the network. The asynchronous nature of ATM means that bandwidth is made available on demand instead of allocating slots of transmission time to network devices, as is the case in a synchronous system employing Time-Division Multiplexing (TDM).

ATM employs fixed-sized cells of 53 bytes each as the basic unit of transmission. Each cell consists of a 5-octet header, identifying the source of the transmission, among other information, and a 48-octet payload containing the user data and headers for higher-level protocols. This architecture permits data ranging from text, voice, graphics, and video to share the same network without any one source dominating network bandwidth.

ATM employs a star topology with an ATM switch acting as the hub of the network. All devices are connected directly to this hub, making network configuration and troubleshooting more straightforward, as well as offering dedicated bandwidth to the central switch.

How you can use ATM on a filer

You can use ATM in two ways on a filer:

The filer can simultaneously support Fore/IP over SPANS as well as LANE over UNI 3.0 or 3.1 on the same physical interface.


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Part No. 210-02334
File: atm1.htm
Last updated: 02/24/99 12:16:13