Supporting Released Flows that are Subsequently Hairpinned back to the SBC

The Oracle Communications Session Border Controller (SBC) allows you to quickly re-establish media flows for released calls that may be hairpinned back the SBC by other network elements.

When the SBC releases a media flow, it also deletes information related to that flow by default. For a call that the environment subsequently hairpins back to the SBC, there is a delay in determining how to forward it. You can configure the SBC to retain IP/port information for all released calls to cause it to quickly process and forward these calls. To do this, you configure the media-manager with the hairpin-released-flows option.

ORACLE(media-manager)# options +hairpin-released-flows

This configuration makes the SBC store the IP/port information of the released media port sent out in the SDP. Should a proxy or media server send the media connection with that IP/port back to the SBC, the SBC recognizes the leg and performs the proper linking between the flows.

Recall that you determine whether the SBC releases or manages media using the mm-in-realm, mm-in-network, mm-same-ip and mm-in-system settings in the realm configuration.