The T1 and E1 inverse multiplexing over ATM (IMA) port adapters use IMA technology to aggregate multiple low-speed links into one larger virtual trunk or IMA group. An inverse multiplexer appears to your ATM switch router as one logical pipe. IMA provides you with modular bandwidth to access the ATM network between T1 or E1 and T3 or E3 rates.IMA requires inverse multiplexing and demultiplexing of ATM cells in a cyclical fashion among links grouped to form higher bandwidth logical group with a rate approximately the sum of the link rates. This is called an IMA group. You can combine up to a maximum of eight T1 and E1 lines to form an IMA group.