Propagate From Header (SIP to SIP)

1 Call Flow Diagram
2 Configuration
- 2.1 Initial Configuration
- 2.2 Enable SIP Privacy
- 2.3 Create a SIP Profile (SGP) and SIP Headers page
- 2.4 Create a Remote Gateway
- 2.5 Configure SIP Signaling
3 Additional Information

Feature F-5545 Propagate From Header between SIP calls is applied when the IMG 2020 is within a Trusted Domain and the SIP Privacy functionality is enabled. If SIP Privacy is set to Disabled, the Propagate From Header feature does not function.

During a SIP to SIP call the IMG 2020 can receive an INVITE message with a From Header, a P-Asserted Identity Header, a Remote Party ID Header or some combination of each. Each of these headers has a username attached. The Propagate From Header between SIP Calls feature enables or disables which username from the From Header, P-Asserted Identity Header, or Remote Party-ID header will be propagated to the outgoing INVITE.

The Propagate From Header between SIP calls feature is configured through a combination of the Username Bypassed field in the From Header Tags object and the Privacy field setting in the SIP Profile object. Below is a table displaying how the username from these various headers is interworked. As displayed in the table, it is a combination of this feature and the SIP Privacy setting that determines the outgoing username.

SIP Privacy Setting	Received in the incoming INVITE	Username Bypass set to Enable	Username Bypass set to Disable
Disabled	From Header P-Asserted Header	The Username Bypass setting is a Don't Care. The username in the From Header of the incoming INVITE message is propagated to the From Header. The P-Asserted is not propagated (Refer to 1st Call Flow Diagram below)	The Username Bypass setting is a Don't Care. The username in the From Header of the incoming INVITE message is propagated to the From Header. The P-Asserted is not propagated (Refer to 1st Call Flow Diagram below)
PAID Only	From Header P-Asserted Header	The username in the From Header of the incoming INVITE message is propagated to the From Header on the Outgoing INVITE message. The username of the P-Asserted Identity Header on the incoming INVITE message is propagated to the outgoing P-Asserted Identity Header. (Refer to 2nd Call Flow Diagram below)	The username in the P-Asserted ID Header of the incoming INVITE message is propagated to both the From Header and P-Asserted Header on the Outgoing INVITE message. (Refer to 3rd Call Flow Diagram below)
RPID Only	From Header RPID Header	The username in the From Header of the incoming INVITE message is propagated to the From Header on the Outgoing INVITE message. The username of the Remote Party ID Header on the incoming INVITE message is propagated to the outgoing Remote Party ID Header. (Refer to 2nd Call Flow Diagram below)	The username in the Remote Party ID Header of the incoming INVITE message is propagated to both the From Header and the Remote Party ID Header on the Outgoing INVITE message. (Refer to 3rd Call Flow Diagram below)
Both	From Header P-Asserted Header RPID Header	The username in the From Header of the incoming INVITE message is propagated to the From Header on the Outgoing INVITE message. The username in the P-Asserted Identity Header of the incoming INVITE message is propagated to the outgoing P-Asserted Identity Header. The username of the Remote Party ID Header on the incoming INVITE message is propagated to the outgoing Remote Party ID Header. (Refer to 2nd Call Flow Diagram below)	The username in the P-Asserted ID Header of the incoming INVITE message is propagated to the From Header, the P-Asserted ID Header, and the Remote Party ID Header on the Outgoing INVITE message. (Refer to 3rd Call Flow Diagram below)

Call Flow Diagram

The call flows below display the functionality for each of the different states that could be configured for the Propagate the From Header on SIP to SIP call with Privacy feature.

SIP Privacy = Disabled; UserName Bypassed = Don't Care

If SIP Privacy is Disabled, the Propagate From Header between SIP calls feature will not function. SIP Privacy needs to be Enabled before configuring the UserName Bypassed field in the SIP From Header Tags object. Refer to call flow below.

SIP Privacy = Enabled; UserName Bypassed = Enable (Default)

In the call flow below, the IMG 2020 receives an INVITE request. The username in the From Header is 1111 and the username in the P-Asserted Identity Header is 2222. With both SIP Privacy enabled and the UserName Bypassed field in the SIP From Header Tags object set to Enable, the username in the From Header is propagated to the outgoing INVITE message. The P-Asserted Identity Header username is propagated as well. Refer to call flow below.

SIP Privacy = Enabled; UserName Bypassed = Disable

In the call flow below, the IMG 2020 receives an INVITE request. The username in the From Header is 1111 and the username in the P-Asserted Identity Header is 2222. With SIP Privacy enabled and the UserName Bypassed field in the SIP From Header Tags object set to Disable, the username in the From Header is not propagated to the outgoing INVITE message. The P-Asserted Identity Header username is propagated to both the From Header username and the P-Asserted Identity Header as well. Refer to call flow below.

Configuration

Initial Configuration

The procedure below explains how to configure the IMG 2020 to Propagate the username in the From Header on the incoming leg to the username in the From Header on the outgoing leg while SIP Privacy is enabled. Before configuring, the IMG 2020 must have an initial configuration created on it. Follow the Basic Configurations procedure before proceeding.

Enable SIP Privacy

The Propagate the From Header on SIP to SIP call with Privacy feature functions only when Privacy is enabled on the IMG 2020. Refer to the topic for information on enabling SIP Privacy.

Create a SIP Profile (SGP) and SIP Headers page

Configure the SIP Profile and then the SIP From Header Tags Headers object. In the SIP From Header Tags object, enable the Username Bypass field. Refer to procedure below.

Right click on the Profiles object and select New SIP Profiles. The SIP Profiles object is a parent or container object. No configuration is needed here. Refer to the SIP Profiles topic for more information on this object.
Right click on the SIP Profiles object and select New SIP Profile. The first profile that gets created is a Default SIP Profile and cannot be modified. Disregard this profile.
Right click on the SIP Profiles object and select New SIP Profile again. In the SIP Profile object that appears, either enter a name that identifies this SIP Profile or accept the default name already entered. In this example the SIP Profile was labeled SIP_PropFromHeader_Profile. Refer to the SIP Profile - SGP topic for information on configuring the remaining fields in this object.
Right click on the SIP Profile object just created and select New SIP from Header Tags. Verify the UserName Bypassed field is set to Enable. This is by default set to Enable.

Since the UserName Bypassed field is initially set to Enable, the Propagate From: Header (SIP to SIP) functionality is also initially set to Enabled. If the setup being configured uses Privacy between SIP and SS7, or SIP and ISDN, the UserName Bypassed field in the SIP From Header Tags object must be manually modified to Disable. This is explained in the topic.

Create a Remote Gateway

Create an External Gateway object. This will link the SIP Profile created above with an External Remote Gateway. Follow procedure below.

Right click on the Dialogic object and select New External Network Elements. The External Network Elements object is a parent or container object and no configuration is needed here. Refer to External Network Elements topic for more information.
Right click on External Network Elements and select New External Gateways. The External Gateways object is a parent or container object also and no configuration is needed here. Refer to External Gateways for more information.
Right click on External Gateways and select New External Gateway. Enter a name that identifies the gateway being configured. In this example the gateway was labeled SIP_PropFromHeader_GW.

Select SIP from drop down menu in the Gateway Signaling Protocol field.
Enter an IP address for this gateway.
Select the SIP Profile (SGP) created earlier from drop down menu in the SIP Profile field.

Configure SIP Signaling

The configuration above displays how to configure the SIP Profile and External SIP Gateway so that the Propagate From Header functionality is configured. The next step is to configure the SIP signaling stack and SIP Channel Groups. Refer to the Configure SIP (Single SIP IP) topic for a procedure on how to configure the SIP functionality.

Additional Information

The Propagate From Header on SIP to SIP call with Privacy feature is supported when the A leg and B leg are both using SIP.
The Propagate From Header on SIP to SIP call with Privacy feature is supported only when Privacy is enabled.
In the scenario where SIP Privacy is configured as Both and the Propagate From Header on SIP to SIP call with Privacy feature is Disabled (UserName Bypass = Disable), if both a P-Asserted Identity Header and a P-Preferred Identity header are received in the incoming INVITE, the IMG 2020 will propagate the username of the P-Asserted Identity Header to the outgoing leg. The P-Asserted Identity header always takes precedence.

Dialogic Integrated Media Gateways