Nowadays, most us
are surrounded by powerful computer systems with graphics oriented input and output.These
computers include the entire spectrum of PCs, through professional workstations
upto super-computers. As the performance of computers has increased, so too has
the demand for communication between all systems for exchanging data, or between
central servers and the associated host computer system.
The
replacement of copper with fiber and the advancement sin digital communication
and encoding are at the heart of several developments that will change the communication
infrastructure. The former development has provided us with huge amount of transmission
bandwidth. While the latter has made the transmission of all information including
voice and video through a packet switched network possible.With continuously work
sharing over large distances, including international communication, the systems
must be interconnected via wide area networks with increasing demands for higher
bit rates.For the first time, a single communications technology meets LAN and
WAN requirements and handles a wide variety of current and emerging applications.
ATM is the first technology to provide a common format for bursts of high speed
data and the ebb and flow of the typical voice phone call. Seamless ATM networks
provide desktop-to-desktop multimedia networking over single technology, high
bandwidth, low latency network, removing the boundary between LAN WAN.
ATM
is simply a Data Link Layer protocol. It is asynchronous in the sense that the
recurrence of the cells containing information from an individual user is not
necessarily periodic. It is the technology of choice for evolving B-ISDN (Board
Integrated Services Digital Network), for next generation LANs and WANs. ATM supports
transmission speeds of 155Mbits / sec. In the future. Photonic approaches have
made the advent of ATM switches feasible, and an evolution towards an all packetized,
unified, broadband telecommunications and data communication world based on ATM
is taking place.
