Asynchronous Transfer Mode is, according to the ATM Forum, "a telecommunications concept defined by ANSI and ITU standards for carriage of a complete range of user traffic, including voice, data, and video signals," and is designed to unify telecommunication and computer networks. It uses asynchronous time-division multiplexing, and it encodes data into small, fixed-sized cells. This differs from approaches such as the Internet Protocol or Ethernet that use variable sized packets or frames. ATM provides data link layer services that run over a wide range of OSI physical layer links. ATM has functional similarity with both circuit switched networking and small packet switched networking. It was designed for a network that must handle both traditional high-throughput data traffic, and real-time, low-latency content such as voice and video. ATM uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the actual data exchange begins. ATM is a core protocol used over the SONET/SDH backbone of the public switched telephone network and Integrated Services Digital Network, but its use is declining in favour of all IP. Wikipedia [ - ]

Asynchronous Transfer Mode is, according to the ATM Forum, "a telecommunications concept defined... [ + ]