ATM is also asynchronous, but for a different reason. In this case, we can give up synchronizing our two devices because we put in place other ways of insuring that the data is properly received and processed at the Destination. It can also mean greater capacity. We want to transmit real-time data without errors. Switch all cells with as low a discard rate as possible Never reorder the cells on a virtual circuit.
Small cells mean little is lost if a single cell fails to arrive.
5 byte Header and 48 byte payload. This is a combination of synchronous and asynchronous techniques. Because Hardware is synchronous, we don't have to worry about identifying the beginning and end of cells. Even when used with video or telephony, the input will somehow have to be segmented to fit into an ATM cell or cells. 243 ATM at the Network and Transport Layers.