IMG 1010 - SIP Delayed Media Calls - Outbound

Overview:

Before software version 10.5.3, the IMG supports receiving incoming delayed media SIP calls where the incoming INVITE message does not contain an offer SDP. The IMG would then respond with a 200 OK message containing the offer SDP and negotiations would proceed after receiving ACK for INVITE with answer SDP. F-1666 gives the IMG the ability to generate the outbound delayed media SIP call where INVITE generated does not contain offer SDP. Negotiation will proceed once offer SDP is received from far end provisional response or in final response. The IMG will either pass, release, or cancel the call.

Scenario 1:

IMG generates an INVITE with No SDP (empty INVITE) and sends INVITE to Far End Gateway.
The Far End Gateway responds with a 180 Ringing followed by a 200 OK with SDP (offer) in the response.
The IMG and Far End Gateway negotiate the offer based on local capabilities.
If negotiation is successful, the IMG sends the answer in an ACK message and the call is connected
If negotiation fails, IMG will reject the offer in the ACK by setting the port to 0 and release the call by sending a BYE. See call flows above.

Scenario 2:

IMG generates an INVITE with No SDP (empty INVITE) and sends INVITE to Far End Gateway.
Far End Gateway responds with a non-reliable 183 Session Progress or 180 Ringing with SDP (offer)
IMG ignores this SDP since the SDP came in a non-reliable non failure 183 Session Progress message from the Gateway to the IMG.
The Gateway then sends the SDP in the 200 OK message. Since this is a reliable message, the IMG negotiates the offer based on local capabilities.
If negotiation is successful the IMG sends the answer in an ACK to the gateway.
If negotiation fails, the IMG shall reject the offer (SDP) in the ACK by setting the port to 0 and then release the call by sending a BYE message to the gateway. See call flow diagrams above.

Scenario 3:

IMG generates an INVITE with No SDP (empty INVITE) and sends INVITE to Far End Gateway.
Far end Gateway responds with a reliable 183 Session Progress or 180 Ringing with offer (SDP).
IMG negotiates the offer received in the reliable 183 Session Progress or 180 Ringing with offer (SDP) based on local capabilities.
If negotiation is successful, the IMG will send answer in a PRACK.
If negotiations fail, IMG releases the call by sending CANCEL

Configuration Procedure:

The procedure below explains how to configure the IMG for feature F-1666. Verify the following entities are configured before proceeding:

Configure these initial objects before proceeding to the procedure below.

Create an Signaling Gateway Profile (SGP) for Delayed Media Feature

Right Click on the Profiles object and select New SGP. In the SGP object Enter a Name to identify this object, change the ID to something other than ID:0. Enable the Outbound Delayed Media by selecting ‘Enabled’ from drop down menu. See screen capture below:

See IMG 1010 - SIP Profile - 10.5.3 for more information on configuring the SGP pane.
Right Click on IMG Name and select New Signaling. The Signaling Object is created to allow multiple signaling objects below it. No configuration needs to be accomplished in this object. See IMG 1010 - Signaling Object for information on this object
Right Click on Signaling Object just created and select New SIP. Select the SIP Gateway Profile just created from drop down menu in the Remote IMG’s SIP Profile. See screen capture below:

See IMG 1010 - Configuring SIP Signaling for more information on this object

Creating SIP Channel Groups:

Right Click on Dialogic IMG EMS and select New Routing Configuration. See IMG 1010 - Routing Configuration Object for more information.
Right Click on Routing Configuration and select New Channel Groups. No configuration is needed within the IMG 1010 - Channel Groups object. This object is configured so that multiple Channel Group objects can be configured below it.
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 IMG 1010 - Channel Group for more information on configuring a SIP channel group.

Create an external network element:

An external network element must be created. Configure the external gateway that the SIP channel group will send messages to as the external network element.

Right Click on Dialogic IMG EMS and select New External Network Elements. The External Network Elements object is created to allow multiple external network element objects to be created under it. There is no configuration required in this object. See External Network Elements for more information.
Right Click on External Network Elements object and select New External Gateways. The External Gateways object is created to be able to configure multiple gateways objects to be created under it. There is no configuration required in this object. See IMG 1010 - External Gateways for more information.
Right Click on External Gateways object and select New External Gateway. Enter a name in the ‘Name’ field to identify this gateway. Select SIP from drop down menu in the Gateway Signaling Type field. See IMG 1010 - External Gateway for more information.
- Enter a Name into the Name field.
- Select SIP from drop down menu in the ‘Gateway Signaling Protocol’ field.
- Enter IP address for this gateway
- Select the SIP Gateway Profile (SGP) created earlier from drop down menu in the ‘SIP Profile’ field.

Insert SIP External Network Element into SIP Channel Group:

Right Click on SIP Channel group and select New IP Network Element. Select the Gateway created under the External Network Elements that was just created. See screen capture below:
At this point the feature has been configured. Below is screen capture of the Delayed Media Tree within ClientView.

Dialogic Integrated Media Gateways