Tunnel SIP INFO to ISDN

 

 

After a call between the SIP protocol and the ISDN protocol has been answered and is in progress, a proprietary header within the SIP INFO message can be interworked from the SIP side to the ISDN side. After the call is answered, and the IMG 2020 receives a SIP INFO message with the proprietary header labeled X-DLGCIsdnTunnelingInfo the information that proceeds the header will be interworked into the ISDN side. The header in the SIP INFO message uses the format shown below:

 

X-DLGCIsdnTunnelingInfo: 621c<xxxxxxxxxxxxxxxxxxxx>

 

The information in the header must include 0x621c for the IMG 2020 to take the message and interwork it into the ISDN leg of the call. If the first four bytes are not 0x621c the SIP INFO message will be ignored. Since the 0x621c is a facility message, the feature is used to transfer Malicious Call Trace information from SIP to ISDN. Refer to the information below.

 

Call Flow Diagrams

SIP to ISDN

 

ISDN to SIP

 

Configuration

Below are instructions on how to configure the IMG 2020 to interwork a proprietary header from a SIP Info message to the ISDN side. Before configuring, the IMG 2020 must have an initial configuration created on it. Refer to the procedure and verify the basic functionality has been configured. Also, since the feature uses interworking between the SIP and ISDN protocol, verify that ISDN signaling and ISDN channel groups have been configured. Refer to the topic for information on configuring ISDN.

 

Create SIP SGP and  SIP Headers objects

The SIP Headers object is used to enable/disable the X-Dialogic ISDN Data field. Configure the SIP Headers object as described below.

  1. Right click on the Profiles object and select New SIP SGP. Once SIP SGP pane is created, change the SIP Profile ID to something other than 0 by selecting a different ID from the drop down menu. A SIP SGP Profile with an Id of 0 is a default SIP SGP Profile and cannot be modified. Modifying the SIP Profile Id field will allow user the ability to edit the SIP SGP Profile.

  2. In the SIP Profile Name field, enter a name that describes this profile. In this procedure, the name SIP_XDialogic_Head was entered. Refer to topic for more information on configuring the remaining fields in this object.

  3. Right click on the SIP SGP object and select New SIP Headers. In the SIP Headers object that appears enable the X-Dialogic ISDN Data field. See screen capture below. Refer to topic for more information.

PKN: Need Web GUI screenshot to replace ClientView GUI.

 

Create SIP Signaling Stack

Configure the SIP signaling stack.

  1. Right click on the Signaling object and select New SIP. A SIP Signaling object will appear# In the Remote IMG's SIP Profile field, select the SIP SGP Profile created earlier (SIP_XDialogic_Head). Refer to the topic for more information on configuring the remaining fields in this object.Create SIP Channel Group

  2. Right click on Channel Groups object and select New Channel Group. Set the Signaling Type field to SIP.# In the Name field, enter a name that describes the channel group being configured. In this procedure ChGrp_SIP_XDialogic was entered. Refer to the topic for more information on configuring the remaining fields in the SIP Channel Group object.Create External SIP Gateway

The gateway being created is the network element on the SIP network that the SIP INFO message will be coming from.

  1. Right click on IMG EMS and select New External Network Elements. No configuration is needed here. The External Network Element pane is a parent object to multiple external entities in the network. Refer to topic for more information.

  2. Right click on the External Network Elements object and select New External Gateways. Again, no configuration is needed here. Refer to object for more information.

  3. Right click on External Gateways object and select New External Gateway.

  4. modify the Gateway Signaling Protocol field to display SIP, and enter an IP address in the Gateway IP Address field.

  5. Within the SIP Profile field select the SIP SGP created above for the X-Dialogic ISDN Data feature. See screen capture below. Refer to the External Gateway topic for more information.

PKN: Need Web GUI screenshot to replace ClientView GUI.

 

  • Enter a name to identify this gateway.* Select SIP as the Gateway Signaling Protocol.* Enter the IP address of the Gateway in the Gateway IP Address field.* Select from the drop down menu of the SIP Profile field, the SGP Profile created earlier.* Refer to the topic for more information on configuring the remaining fields.

 

Point SIP Channel group to gateway created

The SIP Channel group created above must point to the external gateway just created.

  1. Right click on the SIP Channel group created above and select New IP Network Element. In the IP Network Element field, select from drop down menu the gateway created above. Refer to the topic for more information on this object. See screen capture below!SC_Facility_Tunn_IPNetElem_Config.png|title=!

PKN: Need Web GUI screenshot to replace ClientView GUI.

  

Route SIP Channel group to ISDN Channel group

At this point the feature has been configured and both the ISDN and SIP channel groups have been configured. Using routing information, route the SIP channel group to the ISDN channel group.

Additional Information

  • Call must be in the answered state for the feature to function.* The ISDN Facility Tunneling is supported in a SIP to ISDN call flow only.* The ISDN Facility Tunneling is supported for Malicious Call Tracing information only.* The ISDN Facility Tunneling is supported in all ISDN variants.* The Proprietary Header the IMG 2020 receives on the SIP side must contain the format X-DLGCIsdnTunnelingInfo: 621c<xxxxx>* If the Proprietary Header is received but the data does not validate (e.g first two bytes are not 0x621c or length is incorrect) the INFO message will be ignored and the IMG 2020 will return a 400 Bad Request [BAD-X-DLGCIsdnTunnelingInfo] header.

 

 

 

 

 

 

 

 

 

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