Using the SDP-Response Early Media Suppression Rule

To use SDP-response early media suppression, you must add the early-media-sdp-realms option to the SIP interface configuration that interfaces with the next-hop device, such as the supported softswitch.

When the Oracle® Enterprise Session Border Controller receives a provisional response that includes SDP from the called endpoint, and the early-media-sdp-realms option is active in the outgoing SIP interface of the call, it first searches the realms that apply to the outgoing SIP interface. If it does not find a realm, the Oracle® Enterprise Session Border Controller searches the global realms. If the search yields a new realm that is not the SIP interface realm, its early media suppression rule (if any) replaces the existing one. Only the early media suppression rule of the new realm is applied to the call. Other realm properties from the outbound realm remain applicable to the call. If no new realm is found, the early media policy of the outgoing SIP interface realm is applied.

TheOracle® Enterprise Session Border Controller allows media when the SDP media connect address in a response matches one of a configured list of IP address ranges defined in a realm and the realm has early media allowed. You need to configure specific a IP address or address range to specify which media gateways should not be suppressed based on SDP media addresses. The IP addresses are checked against the SDP being received. The decision for suppression is based on whether the matching realm allows early media. The early media will be suppressed if the matching realm does not allow early media or if there is no match and the outbound SIP interface ream does not allow early media.