SCTPSctSapReCfg

Dependent function: None.

The following SCTPSctSapReCfg structure contains re-configurable SCT SAP configuration parameters for SCTP. Bold text indicates fields you can modify. Unbolded fields are either unused or for internal use only. They are set to correct values by SctpInitSctSapCfg and must not be overridden.

typedef struct _SctSapReCfg /* SCT SAP Reconfiguration */
{
    U16             maxAckDelayTm;      /* Maximum time delay for generating Acks */
    U16             maxAckDelayDg;      /* Maximum # of datagrams after which an Ack */
                                        /* shall be sent */
    U16             rtoInitial;         /* Initial value of RTO */
    U16             rtoMin;             /* Minimum RTO */
    U16             rtoMax;             /* Maximum RTO */
    U16             freezeTm;           /* Default Freeze timer value */
    U16             cookieLife;         /* Life time for a Valid Cookie */
    U16             intervalTm;         /* Default Heartbeat interval timer value */

    U16             maxBurst;           /* new protocol parameter defined */
    U16             maxHbBurst;         /* new protocol parameter defined */
    U16             t5SdownGrdTm;       /* T5 Shutdown Guard Timer value */

    U16             spare1;             /* alignment */
    Bool            handleInitFlg;      /* Flag to indicate whether SCTP should
                                         * handle INIT itself */
    Bool            negAbrtFlg;         /* Negotiate or Abort the init if MIS is
                                         * less than OS */
    Bool            hBeatEnable;        /* Enable HeartBeat by Default */

    U8              spare2;             /* alignment */
    U32             flcUpThr;           /* Flow Control upper threshold */
    U32             flcLowThr;          /* Flow Control lower threshold */

    U32             spare3;             /* alignment */
} SCTPSctSapReCfg;

SCTPSctSapReCfg is a substructure to SCTPSctSapCfg. Unlike with SCTPSctSapCfg, you can modify the field values for bolded fields at any time.

The following table describes the fields in the SCTPSctSapReCfg structure. Fields not listed in the table are either unused or for internal use only.

Field

Type

Default

Description

maxAckDelayTm

U16

200

Maximum time to wait before the SCTP layer must send a Selective Acknowledgement (SACK) message. Valid range is 1 -165535.

maxAckDelayDg

U16

2

Maximum number of messages to receive before the SCTP layer must send a SACK message. Valid range is 1 - 165535.

rtoInitial

U16

3000

Initial value of the retransmission timer (RTO). The SCTP layer retransmits data after waiting for feedback during this time period. Valid range is 1 - 65535.

rtoMin

U16

1000

Minimum value used for the RTO. If the computed value of RTO is less than rtoMin, the computed value is rounded up to this value.

rtoMax

U16

10000

Maxiumum value used for RTO. If the computed value of RTO is greater than rtoMax, the computed value is rounded down to this value.

cookieLife

U16

60000

Base cookie lifetime for the cookie in the Initiation Acknowledgement (INIT ACK) message.

intervalTm

U16

3000

Default heartbeat interval timer. Valid range is 1 - 65535.

maxBurst

U16

4

Maximum burst value. Valid range is 1 - 65535.

maxHbBrust

U16

1

Maximum number of heartbeats sent at each retransmission timeout (RTO). Valid range is 1 - 65535.

t5SdownGrdTm

U16

15000

Shutdown guard timer value for graceful shutdowns.

negAbrtFlg

Bool

FALSE

Action to take when the receiver's number of incoming streams is less than the sender's number of outgoing streams. Valid values are:

TRUE = Accept incoming stream and continue association.

FALSE = Abort the association.

hBeatEnable

Bool

TRUE

Whether to enable or disable heartbeat by default. Valid values are:

TRUE = Enable heartbeat.

FALSE = Disable heartbeat.

flcUpThr

U32

192

Flow control start threshold. When the number of messages in SCTP’s message queue reaches this value, flow control starts.

flcLowThr

U32

64

Flow control stop threshold. When the number of messages in SCTP’s message queue reaches this value, flow control stops.