ATM stands for Asynchronous Transfer Mode. It is a high speed mode of transporting data from one point to another. With ATM, you are able to transmit voice, data and video in small data packets over a single network. It can carry traffic at speeds up to 622 Mbps. Data is transmitted in fixed length cells which gives it advantages over other methods of data transfer. ATM is a cell switching network which takes data and breaks it into 48 bytes. These bytes are then affixed to a 5 byte header which will contain the source and destination information. The use of cell switching and multiplexing is employed and the information is routed in a calculated manner. This method makes it so that your transmission is constant and has a guaranteed capacity. ATM is unlike other time division multiplexing technologies, which are on a time sharing transmission method. With TDM (time division multiplexing) the user is given a time slot to which he or she can send data. The user can only send data when their turn comes up and if there is no data to be sent, the slot is sent empty. ATM is unlike that in which the slots are based on an on demand system. Like the OSI model of data transmission, the packet is sent with identifying headers so the source is known. ATM networks are made up of switches and endpoints. The switch takes packets from other switches or endpoints. Its responsibility is to update the header, the front end of the data being transmitted and to send it on its way to the destination or endpoint. The endpoint is much like it says, it is the destination of the data packet. Each packet in the network is considered independent of the packet before it and after it. Because of this, the network is called a connectionless network. The information that is transferred is split up into 53 eight bit bytes called octets of equal length. The first five bytes of the cell contain the source and destination information and the rest, the payload. It was...
