SIP Privacy

The 2020 IMG supports SIP Privacy as per RFC 3323 and also supports RFC 3325 which adds the P-Asserted and P-Preferred Identity Headers used within a Trusted Network. SIP Privacy is an extension to SIP that allows parties in a SIP session to withhold their identity and remain anonymous. SIP Privacy is similar to withholding a caller ID in the PSTN. Below are a few reasons why SIP Privacy would be implemented in a network.

RFC 3325 adds the P-Asserted Identity Header which provides network asserted identity to other trusted network elements such as Application Servers and other Call Agents. The 2020 IMG can select on a gateway by gateway basis which gateways are part of this trusted domain or network and which are not. Below is more information on the fields in the SIP privacy page.

 

SIP Privacy is configured in multiple objects as described below:

  1. Set Privacy Support field within the SIP Signaling Stack either P-Asserted only, Remote-Party only, or both. This is a global setting and must be done for SIP Privacy feature to function correctly.
  2. Within the SIP SGP object. The fields Trusted and SIP Privacy can be configured accordingly. See configuration procedure below
  3. The SIP SGP object is then configured to be associated with a specific gateway. See configuration procedure below

 

SIP Privacy Diagram

 

DG_SIP_Privacy.png

 

Call Flow

SIP to PSTN Default Call Flow with Remote-Party-Id

CF_SIP_Privacy_SIP_PSTNDef_RPI.png

 

 

SS7 to SIP Default Call Flow with Remote-Party-Id Translation. No Privacy Requested

CF_SIP_Priv_RemPtyID_NoPRiv.png

 

Configuration

On the 2020 IMG, SIP Privacy is configured in three separate places. Follow procedure below to configure SIP Privacy.

 

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 object. Within the SIP SGP object, the Trusted and SIP Privacy fields can be configured. Once SIP SGP is configured, it can be associated with entities inside and outside of the trusted domain  

  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 to identify this profile.
  3. In the SIP Privacy field, select from drop down menu either ON or Off. If ON is selected then the P-Asserted Identity Header will be displayed in the SIP messaging (Default = Off)
  4. In the Trusted field, select from drop down menu either Yes or No. Trusted is a network of gateways/servers that are part of a Trusted Domain. Will the gateway be part of the trusted domain or not (Default = No). For more information on the SIP SGP page see SIP SGP.

 

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. In the Privacy Support field, select one of the options from the drop down menu. All calls will be handled according to this setting regardless of other SIP Privacy settings on an individual External Gateway or ISDN/ISUP Group.

SC_SIP_Privacy_SIPSig_Config.png

  1. Select the SIP SGP created above from drop down menu in the Remote IMG's SIP Profile field. For more Information refer to SIP Signaling

 

Create an External Gateway:

Configure the external gateway that the SIP channel group will send messages to.

  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. Enter a name in the Name field to identify the gateway being created.

  4. Select SIP from drop down menu in the Gateway Signaling Type field.

  5. Enter an IP address for this gateway

  6. In the SIP Profile field the SIP SGP configured earlier can be selected from drop down menu.

SC_SIP_Privacy_GW_Config.png

 

Note: To enable Privacy for an ISDN Group or an ISUP Group, set the Discard Privacy Info field in the ISDN Group pane or the ISUP Group pane to Yes.

 

Create SIP Channel Groups:

  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.

 

Insert SIP External Network Element into SIP Channel Group:

  1. Right Click on the SIP Channel group created and select New IP Network Element. Within the IP Network Element field, select from drop down menu, the gateway configured earlier. See screen capture below.

SC_SIP_Privacy_IPNetElem_Config.png

  1. Multiple SIP SGP profiles with different privacy settings can be configured. The procedure above can be followed numerous times to create a network of gateways that are either trusted or untrusted and whether SIP Privacy is enabled or not.