SS7 - Destination - ISUP Group - BCI Override

Owned by Kelli Higdon
Last updated: Apr 03, 2024
6 min read

 

After an IAM (Initial Address Message) is sent to a destination endpoint, the destination endpoint returns an ACM (Address Complete Message) indicating that a switched circuit has been established to the requested endpoint. Within the ACM message are parameters labeled as Backward Call Indicators (BCI). The Backwards call indicators send information about call setup back to the called party. The BCI Override object allows the IMG 2020 to either ignore or override any of the indicators it receives in an Alerting message such as an ACM and send them back to the originator with the parameters selected in each of the fields described in the Field Description section below. Use this pane to override/modify any of the Backward Call Indicator parameters. The BCI Override object functions as explained below.

A call comes into the IMG 2020. This call could be of any protocol and has call setup information to be passed to the outgoing side. The setup information is transmitted on the outgoing side as Forward Call Indicators. The far end gateway on the outgoing side receives the IAM message and sends an ACM message back to IMG 2020. The IMG 2020 receives the Backwards Call indicators. The BCI Override object can be configured to do one or all of the described below.

  1. Backward Call Indicator is set to Ignore, all setup information received in the ACM will pass through the IMG 2020 and be transmitted back to the originator.

  2. Backward Call Indicator is set to Override, a default set of values will be automatically set in this object. In this case when the IMG 2020 receives the ACM message, it will ignore the indicators in the ACM and transmit a default set of indicators back to the originator in an ACM message.

  3. Backward Call Indicator is set to Override. The user now has the ability to modify any of the indicators displayed in the BCI Override object. The ACM message sent back to the originator will consist of any default indicator values as well as any modified indicator values. 

It is also possible to override the BCI parameters in the ANM and CPG messages. The configuration is done the same way as for ACM message but from the ANM BCI Override and CPG BCI Override pages. 

Web GUI Page

Dialogic > SS7 > SS7 Network > SS7 Stack > SS7 Destination > ISUP Group > New BCI Override

Dialogic > SS7 > SS7 Network > SS7 Stack > SS7 Destination > ISUP Group > New ANM BCI Override

Dialogic > SS7 > SS7 Network > SS7 Stack > SS7 Destination > ISUP Group > New CPG BCI Override

Maximum Objects

One BCI Override, one ANM BCI Override and one CPG BCI Override object per ISUP Group object.

Related Topics and Dependencies

BCI Override is configured for a specific SS7 ISUP group. Once the ISUP group is configured, the BCI Override object can be configured under it. Each SS7 ISUP Group configured under the SS7 Channel Group can be configured to have the ability to ignore or override certain indicators it receives in an ACM message from a far end gateway. The Backwards Call Indicators parameter sends the ignored or overridden parameters back to originator in the ACM message. The Default is to Ignore overriding the parameters.

SS7 - Destination - ISUP Group - FCI Override

Configure SS7

Field Descriptions

Backward Call Indicator

When the ACM is received, the IMG 2020 can be configured to either  ignore or  override the indicators with values set in fields below.

Ignore (default) - Accept any Backwards Call Indicator values. Transmit them to the originator as they were received.

Override - A set of default values will be set. User can transmit the default values back to originator -or- user can modify any of the Backward Call Indicator parameters. ACM message sent back will consist of both default and modified indicators. (Default values that are displayed in the object will be sent if no value was received for a specific indicator)

Refer to the for bit information on the Backward Call Indicator.

If BCI Override is set to Override, the parameters marked with an asterisk (*) below are the default values selected in the BCI Override Pane and will be available in the outbound IAM message.

Charge Indicator

Charge Indicator parameter will indicate whether a call should be charged as determined by the charging exchange. Values below can be used to override the initial values sent back from IMG 2020 in ACM message.

no indication * - Modify the Charge Indicator on ACM message sent back to originator to no Indication.

no charge - Modify the Charge Indicator on ACM message sent back to originator to no Charge.

charge - Modify the Charge Indicator on ACM message sent back to originator to charge.

 

H

G

F

E

D

C

B

A

No Indication

 

 

 

 

 

 

0

0

No Charge

 

 

 

 

 

 

0

1

Charge

 

 

 

 

 

 

1

0

Spare

 

 

 

 

 

 

1

1 

Called Party Status Indicator

Indicates whether subscriber is free.

no indication * - Modify the Called Party Status Indicator on ACM message sent back to originator to no Indication.

subscriber free - Modify the Called Party Status Indicator on ACM message sent back to originator to subscriber free.

connect when free - Modify the Called Party Status Indicator on ACM message sent back to originator to connect when free.

excessive delay - Modify the Called Party Status Indicator on ACM message sent back to originator to excessive delay.

 

H

G

F

E

D

C

B

A

No Indication

 

 

 

 

0

0

 

 

Subscriber Free

 

 

 

 

0

1

 

 

Connect When Free

 

 

 

 

1

0

 

 

Excessive Delay (ANSI)

 

 

 

 

1

1

 

 

 

Called party category indicator

Indicates the general category of the called party, an ordinary subscriber, or payphone.

no indication * - Modify the Called party category indicator on ACM message sent back to originator to no indication.

ordinary subscriber- Modify the Called party category indicator on ACM message sent back to originator to ordinary subscriber.

payphone- Modify the Called party category indicator on ACM message sent back to originator to payphone.

 

H

G

F

E

D

C

B

A

No Indication

 

 

0

0

 

 

 

 

Ordinary Subscriber

 

 

0

1

 

 

 

 

Payphone

 

 

1

0

 

 

 

 

Spare

 

 

1

  1

 

 

 

  

End to end method indicator

no end-to-end information available *- Modify the End to end method indicator on ACM message sent back to originator to no end-to-end information available.

pass along method available - Modify the End to end method indicator on ACM message sent back to originator to pass along method available.

SCCP method available - Modify the End to end method indicator on ACM message sent back to originator to SCCP method available.

pass along and methods available - Modify the End to end method indicator on ACM message sent back to originator to pass along and methods available.

 

H

G

F

E

D

C

B

A

No end-to-end method available

0

0

 

 

 

 

 

 

Pass along method available

0

1

 

 

 

 

 

 

SCCP method available

1

0

 

 

 

 

 

 

Pass along and SCCP methods available

1

1

 

 

 

 

 

 

Interworking Indicator

no interworking available * - Modify the Interworking Indicator on ACM message sent back to originator to no interworking available.

interworking available - Modify the Interworking Indicator on ACM message sent back to originator to interworking available.

 

H

G

F

E

D

C

B

A

No interworking encountered

 

 

 

 

 

 

 

0

Interworking encountered

 

 

 

 

 

 

 

1

IAM segmentation Indicator

no indication * - Modify the IAM segmentation indicator on ACM message sent back to originator to no indication.

additional information has been received and incorporated into call setup - Modify the IAM segmentation indicator on ACM message sent back to originator to 'additional information has been received and incorporated into call setup.

 

H

G

F

E

D

C

B

A

No indication

 

 

 

 

 

 

0

 

Additional information has been received and incorporated into call setup

 

 

 

 

 

 

1

  

ISUP Indicator

ISUP not used all the way * - Modify the ISUP indicator on ACM message sent back to originator to ISUP not used all the way.

ISUP used all the way - Modify the ISUP indicator on ACM message sent back to originator to ISUP used all the way.

 

H

G

F

E

D

C

B

A

ISUP not used all the way

 

 

 

 

 

0

 

 

ISUP used all the way

 

 

 

 

 

1

 

 

Holding Indicator

holding not required * - Modify the Holding indicator on ACM message sent back to originator to holding not required.

holding required - Modify the Holding indicator on ACM message sent back to originator to holding required.

 

H

G

F

E

D

C

B

A

Holding not required

 

 

 

 

0

 

 

 

Holding required

 

 

 

 

1

 

 

  

ISDN access indicator

terminating access non-ISDN * - Modify the ISDN access indicator on ACM message sent back to originator to terminating access non-ISDN.

terminating access ISDN - Modify the ISDN access indicator on ACM message sent back to originator to terminating access ISDN.

 

H

G

F

E

D

C

B

A

Terminating access non-ISDN

 

 

 

0

 

 

 

 

Terminating access ISDN

 

 

 

1

 

 

 

  

Echo control device indicator

terminating access non-ISDN * - Modify the Echo control device indicator on ACM message sent back to originator to Incoming half echo control device not included.

terminating access ISDN - Modify the Echo control device indicator on ACM message sent back to originator to Incoming half echo control device included.

 

H

G

F

E

D

C

B

A

Incoming half echo control device not included

 

 

0

 

 

 

 

 

Incoming half echo control device included

 

 

1

 

 

 

 

  

SCCP Method indicator

no indication * - Modify the SCCP Method Indicator on ACM message sent back to originator to no indication.

connection less method available - Modify the SCCP Method Indicator on ACM message sent back to originator to connection less method available.

connection oriented method available - Modify the SCCP Method Indicator on ACM message sent back to originator to connection oriented method available.

connection less and connection oriented methods available - Modify the SCCP Method Indicator on ACM message sent back to originator to connection less and connection oriented methods available.

 

H

G

F

E

D

C

B

A

no indication

0

0

 

 

 

 

 

 

Connection less method available

0

1

 

 

 

 

 

 

Connection oriented method available

1

0

 

 

 

 

 

 

Connection less and connection oriented methods available

1

1

 

 

 

 

 

 

 

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