The full-duplex capability of sessions between two LUs is determined during BIND negotiation. If both applications specify PARMS=(FDX=YES) on the OPEN for the ACB, then all sessions will be full-duplex capable. Otherwise, all sessions will be half-duplex capable. If the BIND exchange results in a full-duplex-capable session, transaction programs are able to send data in an expedited manner, bypassing normal paced protocols. Sessions that are negotiated to a full-duplex-capable level support sending and receiving expedited data whether the conversations are full-duplex or half-duplex. If the BIND exchange does not result in a full-duplex-capable session, sending and receiving expedited data is not supported.