Subscription for Notification of Signaling Path Status

The Oracle Communications Session Border Controllercan explicitly open a flow for the signaling and through a subscription to this flow, provide status change notifications.

The Oracle Communications Session Border Controller supports provisioning of signaling flows to send a Authentication-Authorization Request (AAR) message to the Policy and Charging Rule Function (PCRF) when an endipoint registers, reregisters and deregisters. Service Providers want status information of the signaling flows to be able to react to state changes. By enabling the specific-action-sig-flow-subscription parameter, the Oracle Communications Session Border Controller subscribes for signaling flow status change notifications. The Policy and Charging Rule Function (PCRF) informs the Proxy Call Session Control Function (P-CSCF) when signaling flow state changes have taken place so that the P-CSCF can then take action, e.g. de-registering the User Equipment in the Serving Call Session Control Function (S-CSCF).

The Oracle Communications Session Border ControllerP-CSCF supports the Specific Action attribute value pair (AVP) in conjunction with the AAR being sent to provision a signaling flow. The request to subscribe to this flow status change notifications will enable the handling of either INDICATION_OF_LOSS_OF_BEARER and/or INDICATION_OF_RELEASE_OF_BEARER, the two values of the specific action AVP.

Once enabled, the Oracle Communications Session Border Controller P-CSCF accepts the Re-Authentication Request (RAR) from the PCRF and its notification. The Oracle Communications Session Border Controller P-CSCF replies with a Re-Authentication Authorization acknowledging the RAR as per usual.

When the notification in the RAR is INDICATION_OF_RELEASE_OF_BEARER, the P-CSCF cancels the registration of that UE. The Oracle Communications Session Border Controller deletes the contact on INDICATION_OF_RELEASE_OF_BEARER only if this action is specified in the specific-action-sig-flow-subscription parameter settings. Further action is not taken when the RAR notification is "INDICATION_OF_LOSS_OF_BEARER" as the bearer can be re-established. This notification service is not available for VoLTE.

Subscription for Notification of Signaling Path Status Configuration

To enable specific-action-sig-flow-subscription to receive notifications regarding signal state change information.

1. Access the ext-policy-server configuration element.

   ORACLE# configure terminal
   ORACLE(configure)# media-manager
   ORACLE(media-manager)# ext-policy-server
   ORACLE(ext-policy-server)# 

2. Select the ext-policy-server object to edit.

   ORACLE(ext-policy-server)# select
   <name>:1:  name=extpol1
   
   selection: 1
   ORACLE(ext-policy-server)#

3. specific-action-sig-flow-subscription—Signaling path status changes information available for notification
   • loss of bearer— Within a Re-authorization Request (RAR), this value shall be used when the server reports a loss of a bearer (e.g. in the case of General Packet Radio Service - Packet Data Protocol (GPRS PDP) context bandwidth modification to 0 kbit) to the Application Function (AF). The Service Data Flows (SDFs) that are deactivated as a consequence of this loss of bearer shall be provided within the Flows Attribute Value Pair (AVP). In the Authentication-Authorixation Request (AAR), this value indicates that the AF requests the server to provide a notification at the loss of a bearer.
   • release of bearer— Within a RAR, this value shall be used when the server reports the release of a bearer (e.g. PDP context removal for GPRS) to the AF. The SDFs that are deactivated as a consequence of this release of bearer shall be provided within the Flows AVP. In the AAR, this value indicates that the AF requests the server to provide a notification at the removal of a bearer.tate where the bearer connection has been released.
4. Type done to save your configuration.