The data acknowledge message is used by the application to acknowledge one or more regular or a single expedited data packet from the far end (SCCPDAckRqst) when employing the SCCP connection-oriented services (class 2 or 3). This message is also received by the application to indicate an incoming regular or expedited data ACK packet from a far end point (SCCPDACKIND).
typedef struct sccpDAckRqst
{
SccpNextRS rsn; /* rcv seq. # (M-normal data only- not used for
* expedited */
SccpCredit credit; /* window size (M-normal data only- not used for
* expedited) */
U16 spare1; /* spare for alignment */
} SccpDAckRqst;