Asynchronous Transfer Mode (ATM) :
Asynchronous
transfer mode (ATM) is a switching technique used by telecommunication
networks that uses asynchronous time-division multiplexing to encode
data into small, fixed-sized cells. This is different from Ethernet or
Internet, which use variable packet sizes for data or frames. ATM is the
core protocol used over the synchronous optical network (SONET)
backbone of the integrated digital services network (ISDN).