Asynchronous Transfer Mode - Definition from the Hotspot Shield Glossary
This is a type of data transfer method that involves fixed size packets or cells created by asynchronous time-division. ATM is generally used by ISP’s over long distance networks.
This type of technology is used as an alternative to Ethernet and TCP/IP and features several key differences - Firstly data in an ATM connection travels directly from the source to the end destination with no routing involved. Secondly, ATM data travels in fixed cells of 53 bytes which includes 5 bytes of header info (information on how the cell should be transported and viewed etc.) and 48 bytes of actual data. While Asynchronous Transfer Mode provides a hugely superior connection and traffic speeds, its relative high cost has prevented its wide spread use on the internet backbone.