ATM switches
Cells come in at approx. 150Mbps = 36E04 cells/sec - therefore cycle time of switch is 1/36E04 = 2.7777microsec.
Switch may have from 16 to 1024 input lines. Thus anywhere between 16 to 1024 cells are to be switched every 2.7microsec.
At 622Mbps the time is measured in nanoseconds.