A derivative of the DXI standard, FUNI extends asynchronous transfer mode (ATM) access to smaller sites with relatively low speed access at rates from 56 kbps to 1.544 Mbps (T1). Data enters a router, which encapsulates the data in frames similar to those employed in frame relay.The router then forwards the data to an ATM switch, which converts them to cell format. See also ATM, cell, DXI, frame, frame relay, router, switch, and UNI.