Configure SIP to SIP-T Interworking

Owned by Kelli Higdon
Last updated: Apr 02, 2024
5 min read

 

 

The IMG 2020 supports interworking between SIP and SIP-T. A call originates in the PSTN can be interworked into a SIP network by placing the ISUP messaging into the SIP message body. When the call finally gets to its destination, the ISUP information is extracted from SIP message and placed back into ISUP messaging format so PSTN can now route the call.

The IMG 2020 also supports accepting a SIP message which originally has no ISUP information in the received message and create a SIP-T message which has the ISUP information embedded in its SIP body. Follow the configuration below which describes how to configure the IMG 2020 to accept an incoming SIP message and send out a SIP-T message 

Initial Configuration

To configure SIP to SIPT Interworking, the IMG 2020 must have an initial configuration on it. Refer to the IMG 1010 - Basic Configuration topic and verify the objects in that topic have been completed. 

Configure SS7 Stack

An SS7 stack must be configured. The IMG 2020 will use the SS7 stack information when placing the ISUP message in the SIP body, therefore when creating the stack ensure the correct information is selected in the stack. For information on configuring the SS7 Stack, refer to the Configure SS7 topic. 

Configure SIP Signaling

  1. Right click on the IMG 2020 object and select New Signaling. The Signaling object is a container object and no configuration is needed here. Refer to the Signaling topic for more information on this object.

  2. Right click on the Signaling object created above and select New SIP. In the SIP object that appears, configure SIP-T by selecting Yes from Drop Down menu in the SIP-T Enabled field. Refer to the SIP Signaling - SIP topic for more information on configuring SIP Signaling Pane.

  3. Right click on the SIP Signaling Object and select New SIP-T Entity. A SIP-T Entity object pane will appear.

  4. In the SS7 Stack field, select from the drop down menu the stack created earlier in this procedure. Refer to the SIP Signaling - SIP-T Entity topic for more information on configuring the SIP-T Entity Pane.

Configure a SIP Profile which includes SIP to SIP-T Interworking as an attribute:

  1. Right click on the Profiles object and select New SIP Profiles. The first Profiles object is a Default Profiles object and cannot be modified. Disregard this SIP Profile.

  2. Right click on the Profiles object again and select New SIP Profiles. Modify this SIP Profiles object for your network. Refer to the SIP Profile - SGP topic for information on configuring this object.

  3. Right click on the SIP Profile object and select New SIP to SIP-T Interworking. A SIP to SIP-T Interworking Pane will appear. Select Enabled from the drop down menu in the SIP to SIP-T Interworking field. Refer to the SIP to SIPT Overview topic for information on how to configure the individual fields within this object pane.

Configure External Gateways (Incoming and Outgoing):

The next step will be to configure the external gateways that will be communicating with the IMG 2020.

  • Right click on the Dialogic object and select New External Network Elements. The External Network Elements pane will get created. This is a container object for external gateways. Refer to the External Network Elements topic for more information on configuring this object.

  • Right click on External Network Elements pane and select New External Gateways. From here the individual gateways can get configured. Refer to the External Gateways topic for more information on configuring this object.

  • Right click on External Gateways object and select New External Gateway. In this example the external gateway objects created on the incoming and outgoing side of the IMG 2020 will need the SIP to SIP-T profile enabled. Refer to the screen capture below on how to enable the SIP to SIP-T profile on the incoming gateway. Refer to the External Gateway topic for more information on configuring an external gateway object.



  • Configure an External Gateway on the Outgoing side of the IMG 2020 also. Follow steps above to accomplish configuring an external gateway on the outgoing side.

Note: In this example SIP to SIP-T profile will be configured on both Incoming and Outgoing Gateways. This way all responses on the incoming side will have ISUP messaging embedded and all SIP messaging on the Outgoing side will have ISUP messaging in them. (Now SIP-T messaging)

Configure Incoming and Outgoing Channel Groups

For this example, an incoming and outgoing channel group will be configured. Both channel groups will enable this feature. Follow steps below to accomplish this task

  • Right click on the Dialogic object and select New Routing Configuration. This is a container object. The Channel groups are configured under this object. Refer to the Routing Configuration topic for more information on configuring this object.

  • Right click on the Routing Configuration Object and select New Channel Groups. A Channel Groups Pane will appear. The individual channel groups are configured under this object. Refer to the Channel Groups topic for more information on configuring this object.

  • Right click on Channel Groups object and select New Channel Group. A channel Group Pane will appear, Enter a Name and select SIP as the Signaling Type. See the Channel Group topic for more information on configuring the Channel Group Pane. In this example, Routes and Translations are not configured. Routing and Translation is explained in multiple other Topics In this WebHelp document.

  • Right click on the Channel Group just created and select New IP Network Element. This is the network element that will be connected to the Channel Group just created. Select from drop down menu the Gateway that will connect to the incoming side of IMG 2020. The drop down list includes all the entities that would be considered a Network Element. See screen capture below.

  • Create a second Channel Group for the Outgoing side along wit its IP Network Element.  And connect the external gateway to it as explained above.

  • Click on the Channel Groups object. The icon displayed will be a yellow exclamation point indicating the configuration has not been sent to the IMG 2020. Click on the Download Resource Tables button and the configuration will get sent.


At this point, the IMG 2020 is configured to accept SIP signaling on the incoming side and send out SIP signaling with ISUP messaging in the body of the SIP message (SIP-T). Also, by enabling SIP-T Interworking on the incoming side the responses sent back to the Gateway on the Incoming side will have ISUP messaging in the body of the SIP responses. The procedure above is solely for explaining the basic configuration of the SIP to SIP-T interworking feature. Information such as routing, translation, and other panes can be found on their respective topic links in this online documentation.

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