Patent ID: 8606241

Claim:
A method of providing a terminal-based ringback tone substitute service in a system having a caller-side Mobile Switching Center (MSC), a receiver-side MSC, a Home Location Register (HLR), and a Voice Message Service (VMS) server, the method comprising: receiving a request for an originating call for voice communication with a called terminal from a calling terminal; transmitting a ringback tone start message to the calling terminal, the ringback tone start message being a control message informative of beginning of a ringback tone section performed by the calling terminal, the ringback tone section comprising: determining if a ringback tone substitute sound source is stored in the calling terminal; after the determination that the ringback tone substitute sound source is stored in the calling terminal, activating an audio codec of the calling terminal, decoding the ringback tone substitute sound source by using the audio codec, and playing the ringback tone substitute sound source; and after the determination that the ringback tone substitute sound source is not stored in the calling terminal, activating a voice codec of the calling terminal, and processing signals received from the system by using the voice codec, the voice codec being different from the audio codec; paging the called terminal; transmitting a ringback tone termination message to the calling terminal, the ringback tone termination message being a control message informative of ending of the ringback tone section, and connecting the voice communication between the calling terminal and the called terminal when a response to paging is received from the called terminal, the connecting the voice communication comprising activating, by the calling terminal, the voice codec of the calling terminal, decoding sounds for the voice communication by using the voice codec, and playing the sounds; and transmitting the ringback tone termination message to the calling terminal and transmitting a voice guide message to the calling terminal when no response to the paging is received from the called terminal.