SIP INFO Method - Long Call Duration Auditing

The feature Long Call Duration Auditing uses the SIP INFO Method to verify whether a call is in progress. When the 2020 IMG receives a SIP INFO request with id and tags that match an active call, a 200 OK response indicating that the call is in progress will be sent from the 2020 IMG. If the 2020 IMG receives a SIP INFO request with id and tags that do not match an active call, then a response of '481 Call Leg/Transaction Does Not Exist' is sent from the 2020 IMG. The initiator of the SIP message will then be able to determine if call is up or not. Below are call flows for each scenario.

 

 

Call Flow 1

The call is in progress and Dialog was found. The 2020 IMG sends back a 200 OK message

CF_SIP_INFO_LCDA_OK.png

 

 

Call Flow 2

The call is no longer in progress and Dialog was not found. The 2020 IMG sends back a 481 Call Does not exist message.

CF_SIP_INFO_LCDA_DoesNotExist.png

 

Configuration

The Long Call Duration Auditing feature is Disabled by default. To enable the feature you must select enable in the INFO Keep-Alive Support field in the SIP SGP profile. See procedure below.

 

Initial Configuration:

The procedure below explains how to configure SIP Privacy on the 2020 IMG. Before configuring, the 2020 IMG must have an initial configuration created on it. Follow the Basic Configurations procedure before proceeding.

 

Create SIP Signaling Gateway Profile (SGP)

Create a SIP SGP and SIP DTMF support objects.

  1. Right Click on the Profiles object and select New SIP SGP. Change the SIP Profile ID to something other than ID:0. By doing this, the other fields within the SIP SGP object can now be modified.

  2. In the SIP SGP object enter a name in the SIP Profile Name field. This will identify the profile being created.

  3. Click in the INFO Keep-Alive Support field and select Enable from drop down menu. This will enable the Long Call Duration Auditing feature. The INFO Keep-Alive field is by default set to Disable. Refer to SIP SGP for more information.

 

Create SIP signaling stack

  1. Right Click on 2020 IMG Name and select New Signaling. The Signaling Object allows multiple signaling objects to be configured below it. No configuration is needed in this object.

  2. Right Click on Signaling Object just created and select New SIP. Select the SIP Gateway Profile (SIP SGP) just created from drop down menu in the Remote IMG’s SIP Profile field. See screen capture below. For more Information refer to SIP Signaling

 

Create SIP Channel Group

  1. Right Click on Dialogic IMG EMS and select New Routing Configuration. See Routing Configuration for more information.

  2. Right Click on Routing Configuration and select New Channel Groups. The Channel Groups object allows multiple channel groups to be created under it. There is no configuration required in this object.

  3. Right Click on Channel Groups object and select New Channel Group. Enter a name to identify this channel group and change the Signaling Type to SIP using the drop down menu. See SIP Channel Group for more information on configuring a SIP channel group.

 

Create an External Network Element:

Configure an external gateway and add the SIP SGP profile to it.

  1. Right Click on Dialogic IMG EMS and select New External Network Elements. The External Network Elements object allows multiple external network element objects to be created under it. There is no configuration required in this object. Refer to the External Network Elements topic for more information.

  2. Right Click on External Network Elements object and select New External Gateways. The External Gateways object allows multiple gateway objects to be created under it. There is no configuration required in this object. Refer to the External Gateways topic for more information.

  3. Right Click on External Gateways object and select New External Gateway. See screen capture below. Refer to External Gateway for more information on configuring the External Gateway object.

 

Insert SIP External Network Element into SIP Channel Group:

  1. Right Click on SIP Channel group and select New IP Network Element. Select the Gateway configured earlier from the drop down menu in the IP Network Element field.