Where a separate bearer channel is required to be set up in a mobile network to complete a hybrid VoIP call on the mobile network as specified in 3GPP ICS standard TR 23.892, an alerting process may be started after a provisionable delay rather than upon completion of the network call setup. This allows the mobile network user to start responding to the impending call before signaling of the call has been completed, so that the person can answer closer in time to completion of call signaling. Additionally, the person who placed the call may be provided with ringing feedback to make it sound like the call has been completed. The amount of delay between receipt of a SIP invite and the onset of an alerting process may be specified in the mobile handset or may be specified as a header in the SIP invite. The amount of delay may be fixed or adjusted based on feedback.
