ATM  - Asynchronous Transfer Mode

ATM - A transfer mode in which data is transmitted in the form of 53 byte
units called cells.  Each cell consists of a 5 byte header and a 48 byte
payload.  The term "asynchronous" in this context refers to the fact that
cells from any one particular source need not be periodically spaced
within the overall cell stream.  In other words, users are not assigned a
set position in a recurring frame as is common in circuit switching. 

Keywords: ATM
See Also: ATM UNI Cell Structure