SCTP configuration reference

This topic presents the SCTP configuration file parameters:

All timer values are in milliseconds.

General SCTP

The following table describes the SCTP general configuration parameters:

Parameter

Default

Description

MAX_ASSOC

4

Maximum number of SCTP associations the service user can open simultaneously. Valid range is 1 - 65535.

MAX_DEST_ADDRS

8

Maximum number of destination addresses that can be active simultaneously in SCTP. Valid range is 1 - 65535.

MAX_TX_QUEUE

256

Maximum number of datagrams that can be queued for sending to the peer. Valid range is 1 - the result of (2^32-1).

MAX_RX_QUEUE

256

Maximum number of datagrams received from the peer that can be queue before being sent up to the service user. Valid range is 1 - the result of (2^32-1).

MAX_INSTREAM

8

Maximum number of incoming streams per association. Valid range is 1 - 65545.

MAX_OUTSTREAM

8

Maximum number of outgoing streams per association. Valid range is 1 - 65545.

MTU_INITIAL

1400

Initial path max transmit unit (MTU) in bytes. Valid range is 1 - 1400.

MTU_MAX

1400

Maximum value in bytes to be used in searching for an optimal MTU size using the midpoint algorithm. This field is mandatory if the value of the PERFORM_MTU parameter is TRUE. Valid range is 1 - 1400.

MTU_MIN

500

Minimum value in bytes to be used in searching for an optimal MTU size using the midpoint algorithm. This field is mandatory if the value of the PERFORM_MTU parameter is TRUE. Valid range is 1 - 1400.

PERFORM_MTU

FALSE

Indicates whether or not to perform MTU discovery. Valid values are:

TRUE = Perform MTU discovery.

FALSE = Do not perform MTU discovery.

HOSTNAME

NULL

Self-hostname.

USE_HOSTNAME

FALSE

Whether or not to send hostname in INIT (Initiation) / INIT ACK (Initiation Acknowledgement).

MAX_INIT_RETRY

0

Maximum number of retries for INIT message to open an association. Valid range is 0 - 255. Set to 0 to retry indefinitely.

When MAX_INIT_RETRY number of sends is reached, SCTP terminates the association and M3UA immediately attempts to establish another association The INIT for this new association will contain new TSN and InitTag parameters.

MAX_ASSOC_RETRY

10

Maximum retransmissions for an association. Valid range is 0 - 255.

MAX_DEST_RETRY

5

Maximum retransmissions for a destination address. Valid range is 0 - 255.

ACCEPT_ALT

FALSE

TRUE = Accepts additional lifetime parameters from the peer to extend cookie lifetime.

FALSE = Does not accept additional lifetime parameters from the peer to extend cookie lifetime.

TMR_MD5_KEY

60000

Lifetime of an MD5 key. A new private key is generated every time this timer expires. Valid range is 1 - 65535.

RTT_ALPHA

12

Used for round trip time (RTT) calculations. Valid range is 0 - 65535.

RTT_BETA

25

Used for RTT calculations. Valid range is 0 - 65535.

TRACE_DATA

FALSE

Turns data tracing on or off. Data tracing is sent to the ss7trace utility. Refer to the Dialogic® TX Series SS7 Boards TX Utilities Manual for information about ss7trace. Data tracing can also be turned on or off through the sctpmgr utility. Refer to the Dialogic® NaturalAccess™ SIGTRAN Stack Developer's Reference Manual  for information about sctpmgr.

DEBUG_LOG

FALSE

Turns debug logging on or off. Debug logging is sent to the txalarm utility. Refer to the Dialogic® TX Series SS7 Boards TX Utilities Manual for information about txalarm. Debug logging can also be turned on or off through the sctpmgr utility. Refer to the Dialogic® NaturalAccess™ SIGTRAN Stack Developer's Reference Manual  for information about sctpmgr.

END

N/A

Marks the end of this general SCTP definition. This parameter is required.


SCT Upper SAP

The following table describes the SCT upper SAP configuration parameters:

Parameter

Default

Description

SCT_SAP_ID

0

SAP ID used by the upper layer (M3UA). This identifier must be specified and must be 0.

TMR_ACK_DELAY

200

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

NMB_ACK_DELAY

2

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

TMR_INIT_RTO

3000

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

TMR_MIN_RTO

1000

Minimum value used for the RTO. If the computed value of RTO is less than TMR_MIN_RTO, the computed value is rounded up to this value. Valid range is 1 - 65535.

TMR_MAX_RTO

10000

Maximum value used for RTO. If the computed value of RTO is greater than TMR_MAX_RTO, the computed value is rounded down to this value. Valid range is 1 - 65535.

TMR_COOKIE_LIFE

60000

Base cookie lifetime for the cookie in the INIT ACK (Initiation Acknowledgement) message. Valid range is 1 - 65535.

TMR_HB_INTERVAL

3000

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

MAX_BURST

4

Maximum burst value. Valid range is 1 - 65535.

MAX_HB_BURST

1

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

ABORT_ON_STREAM

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.

ENABLE_HEARTBEAT

TRUE

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

TRUE = Enable heartbeat (recommended for allowing earlier detection of loss of associations).

FALSE = Disable heartbeat.

FLOW_START_THR

192

Number of messages waiting in queue, when flow control indication is sent to the service user (M3UA) to inform it that the queue is nearly full. Valid range is FLOW_STOP_THR to MAX_TX_QUEUE.

FLOW_STOP_THR

64

Number of messages waiting in queue, when flow control indication is sent to the service user (M3UA)  to inform it that the queue is almost empty. Valid range is 0 to FLOW_START_THR.

TMR_SD_GUARD

15000

Shutdown guard timer for graceful shutdowns. Valid range is 1 - 65535.

END

N/A

Marks the end of this SCT upper SAP definition. This parameter is required.


SCT Lower SAP (TSAP)

The following table describes the SCT lower SAP (TSAP) parameters:

Parameter

Default

Description

TSAP_ID

0

Service user ID for the TSAP being configured. This must be 0.

SAP_ID

0

Service provider ID of the TSAP to which this TSAP binds. This must be 0.

MAX_BIND_RETRY

3

Maximum number of bind request retries allowed.

TMR_CFM

200

Time interval for which the SCTP layer waits for bind or status confirmations from the lower layer.

END

N/A

Marks the end of this SCT lower SAP (TSAP) definition. This parameter is required.