WO2006075809A1

WO2006075809A1 - Method and apparatus for providing sounds for substitutiing ringback tones

Info

Publication number: WO2006075809A1
Application number: PCT/KR2005/000099
Authority: WO
Inventors: Tae-Hwan Weon
Original assignee: Eluon Corporation
Priority date: 2005-01-12
Filing date: 2005-01-12
Publication date: 2006-07-20

Abstract

In the prior art, there is a disadvantage that only uniformed ringback tone is provided, and there is limitations in providing ringback tone substituting sound. According to the present invention, the present method, conducted by the terminating exchange, is to provide sounds for substituting ringback tones by the terminating exchange corresponding to the called terminal and being coupled to the originating exchange corresponding to the calling terminal, the home exchange where the called terminal is registered, and the ringback tone substituting sound generator, through the telecommunication network, comprising of the steps of; receiving a call connection request signal from the originating exchange; corresponded to the received signal, transmitting a call connection request signal to the called terminal; transmitting the call connection request signal to the home exchange wherein the call connection request signal includes the identifier of the called terminal, wherein corresponded to the signal received from the terminating exchange, the home exchange transmits a call connection request signal to the ringback tone substituting sound generator, and the ringback tone substituting sound generator extracts a ringback tone substituting sound for the called terminal and transmits the selected sound, through the established trunk connection, to the calling terminal.

Description

METHOD AND APPARATUS FOR PROVIDING SOUNDS FOR SUBSTITUTIING RINGBACK TONES

Technical Field

[1] The present invention relates to a method and apparatus for providing sounds for substituting ringback tones.

Background Art

[2] When a subscriber calls another in a Public Switched Telephone Network (PSTN) or a mobile communication network, the terminating exchange managing the called terminal provides a uniformed ringback tone to the calling terminal according to the specification of the International Telecommunication Union-Telecommunication (ITU-T). Generally, a ringback tone refers to a signal tone provided to the calling terminal according to the specification of ITU-T when a subscriber makes a call to the called terminal through a telecommunication network.

[3] Fig. 1, Fig.2, and Fig. 3 are simplified drawings of the exchange having a T-S-T

(Time-Space-Time) switching structure for offering ringback tone in the prior art.

[4] Referring to Fig. 1, a local call that call origination and call termination are processed within a T-S-T switching structured exchange is comprised of the Calling Subscriber Interface Module 101, the Space Switch 105 and the Called Subscriber Interface module 103.

[5] In case of the local call which is originated and terminated though a PSTN, the

Calling Subscriber Interface Module 101 establishes a switching path to the Called Subscriber Interface Module 103 that is determined by the Call Control Block. Thereafter, the Called Subscriber Interface Module 103 transmits the tone created from the internal tone generator to the specific slot in the Time Switch of the called subscriber. Through above-described process, the tone created from the tone generator can be provided to the calling terminal.

[6] In case of the local call which is originated and terminated through the mobile communication network, when a calling terminal attempts to place a call to a called terminal, the Called Subscriber Interface Module 103 is not determined until the called terminal respond to the paging. Therefore, it is decided that the called terminal belongs to which Called-subscriber Interface Module after the tone generated in the Calling Subscriber Interface Module 101 is provided in response to the paging. Accordingly, the ringback tone generated in the Called Subscriber Interface Module 103 can be provided to the calling terminal as a T-S-T switching path is established after the called terminal responds until the called subscriber answers. [7] Referring to Fig. 2, it is an embodiment of the present invention in the case that call origination and call termination are processed in different exchanges separately. This is also applied in the case that several tandem/toll exchanges are participating in a call delivery from an originating exchange to a terminating exchange in a PSTN. That is, after a call is originated from the calling terminal and signal processing of transmitting IAM (Initial Address Message) and ACM (Address Complete Message) is completed between the originating exchange and the final terminating exchange, a certain channel of the Tl or El trunk is allocated to the originating exchange and the final terminating exchange. Therefore, the ringback tone from the Called Subscriber Interface Module 103 of the final terminating exchange is transmitted to the calling terminal.

[8] It is also applied in the case that several tandem/toll exchanges are participating in a call delivery from an originating exchange to a terminating exchange in a mobile communication network. That is, after a call is originated from the calling terminal and signal processing of transmitting IAM and ACM is completed between the originating exchange and the final terminating exchange, a certain channel of the Tl or El trunk is allocated to the originating exchange and the final terminating exchange. Therefore, the ringback tone from the Called Subscriber Interface Module 103 of the final terminating exchange is transmitted to the calling terminal. However, if it is before the response to the paging, a ringback tone from the Space Switch part 105 of the terminating exchange is transmitted to the calling terminal, and if it is after the response to the paging, a ringback tone from the Called Subscriber Interface Module 103 is transmitted.

[9] Referring to Fig. 3, it is an embodiment of the present invention in the case that call origination and call termination are processed by the different network operators separately. In both cases of PSTN and mobile communication network, after signal processing of transmitting IAM and ACM is completed between the gateway exchange in the originating network and the gateway exchange in the terminating network, the Space Switching part 105 of the gateway exchange in the terminating network can transmit a progressive tone as an option of the operator, because before finding the location of the mobile terminal a caller s waiting time without any tone notification becomes longer by the reason of the signal processing time as the number of tandem/ toll exchanges are increased. Thereafter, after the location of the called terminal is found and signal processing of transmitting IAM and ACM is completed between the gateway exchange in the terminating network and the final terminating exchange, a ringback tone from the tone generator in the Space Switch part 105 of the terminating exchange is transmitted to the calling terminal before the response to the paging, and a ringback tone from the Called Subscriber Interface Module is transmitted until the called subscriber answers after determining the Called Subscriber Interface Module in the response to the paging.

[10] In the prior art described above, there is a disadvantage that only uniformed ringback tone is provided to the calling terminal. In order to solve this disadvantage, the prior invention titled METHOD AND APPARATUS FOR GENERATING TER- MINAΗONER SELECTED SUBSTITUTES OF RINGBACK TONES IN WIRED, WIRELESS TELECOMMUNICATION NETWORK and applied at 6 October 1999 (application number 10-1999-0042987) is published at 15 January 2000. Above- mentioned prior invention will be described with reference to Fig. 4.

[11] Fig. 4 is a sequence diagram showing a signal flow in detail for offering ringback tone in accordance with the prior art.

[12] Referring to Fig. 4, the originating MSC/VLR 10 transmits a LocReq (Location

Request) message requiring the location information of the called terminal to the HLR (Home Location Register 20). The HLR 20 transmits a RoutReq (Routing Request) message requiring the routing number for connecting to the called terminal to the terminating MSC/VLR 30 at step 203. As a result, the terminating MSC/VLR 30 returns a routreq message including TLDN (Temporary Local Directory Number) information which is assigned temporarily to identify the called terminal during the call setup to the HLR 20 at step 205. Then, the HLR 20 returns a locareq message to the originating MSC/VLR 10 at step 207. As a result, a proper announcement or tone is transmitted to the called terminal from the originating MSC/VLR 10 if the called terminal is in power-off or busy state, otherwise an ISUP call processing is started by transmitting an IAM message at step 209.

[13] At step 209, it is determined whether a traditional ringback tone or a ringback tone substituting sound is played to the called terminal according to the value of the specific field representing value-added service of the called terminal stored in the database of the terminating MSC/VLR 30. In case of playing a ringback tone substituting sound, it is in the state that it is not determined what specific ringabck tone substituting sound will be played and where the sound will be loaded. Therefore, the SCP (Service Control Point 40) receives an Analyzed Information message defined in the WIN (Wireless Intelligent Network) standard specification from the originating MSC/VLR 10 at step 211. In this case, the Anainfo (Analyzed Information) message includes MIN (Mobile Identification Number) and the value of the specific field representing whether the ringback tone replacement service is registered or not and containing the routing information of the IP (Intelligent Peripheral) to be used.

[14] Thereafter, at step 213 the SCP 40 requests resource allocation to the IP 50 using a

SeizeRes (Seize Resource Operation) message. At step 215, the IP 50 transmits a TLDN to the SCP 40 in response to the SeizeRes message. The SCP 40 transmits an Analyzed Information message that includes TLDN returned from the IP 50 to the terminating MSC/VLR 30 at step 217.

[15] As a result, the terminating MSC/VLR 30 tries an ISUP call setup using the returned TLDN at step 219. At step 221, the IP 50 invokes an InstReq (Instruction Request) message to the SCP 40 in order to get the information of ringback tone substituting sound corresponding to the specified MIN. In this case, a requesting instruction means a command to specify which ringback tone substituting sound will be selected within the sounds stored in the designated IP. As a result, the SCP 40 queries the database by the MIN to get the information of ringback tone substituting sound, and includes the result in a SRFDir (Specialized Resource Function Directive) message as an output to transmit to the IP 50 at step 223. The IP received the SRFDir message locates the specific ringback tone substituting sound corresponding to the information stored in the received SRFDir and transmits it to the calling terminal at step 225. When the called terminal answers after paging/alerting at step 225 and 227, the terminating MSC/VLR 30 transmits a REL message for the SCP 40 to release the trunk connection at step 229. Also, the terminating MSC/VLR 30 transmits an ISUP ANM message to the originating MSC/VLR 10 at step 227. Through the above-described procedure, the calling terminal can continue a normal call with the called terminal. If the paging is failed (Paging No Response) or there is no answer from the called terminal (No Answer), the terminating MSC/VLR 30 transmits a REL message for the SCP 40 to release the trunk connection between the IP and the terminating MSC/VLR 30. The terminating MSC/VLR 30 releases the trunk connection, plays an announcement defined for this situation to the calling terminal, and then stops the call processing or performs the next step according to the value-added service logic of the called terminal.

[16] In addition to the prior invention described above, a centralized service method is used. However, the above-mentioned prior invention and the centralized service method require an Intelligent Network or Wireless Intelligent Network environment where the IP (Intelligent Peripheral) is connected to the terminating MSC/VLR and new exchange SSP is included in. Therefore, the above-described method has a disadvantage that SSP function should be added on to the existing exchange in order to interface with the SCP/IP. It means that tremendous expenditure is required for adding SSP function to the existing exchange or replacing the exchange to the SSP.

[17] Moreover, there is another disadvantage in the above-mentioned prior invention and the centralized service method that all the value-added service systems interacting with the terminating exchanges must have the whole database of ringback tone substituting sounds, because the terminating exchange in the visited area has to provide ringback tone replacement service when the subscriber roams to other area. That is, whenever a subscriber records new sound and selects it as their own ringback tone substituting sound, all the value-added service systems interacting with the terminating exchanges have to synchronize the database by coping the same sound. In effect, the above- mentioned prior invention and the centralized service method requires a lot of Point Codes to interconnect the value-added service systems. Moreover, there is a disadvantage that the cost for installing and managing those systems is increased exponentially as subscribers increase, because each system must have the duplicated database of the same contents. Disclosure of Invention Technical Problem

[18] An object of the present invention is to provide a method and apparatus for providing sounds for substituting ringback tones that can be used immediately with minimal modification of function of the existing exchanges in the mobile communication network.

[19] Another object of the present invention is to provide a method and apparatus for providing sounds for substituting ringback tones that can reduce a volume of the database storing and managing the ringback tone substituting sounds.

[20] The other object of the present invention is to provide a method and apparatus for providing sounds for substituting ringback tones that can reduce a number of Point Codes, which are network resource of high cost, used for connecting to the terminating exchange. Technical Solution

[21] In order to accomplish the above objects, in accordance with an aspect of the present invention, there is provided a method, conducted by the terminating exchange, for providing sounds for substituting ringback tones by the terminating exchange corresponding to the called terminal and being coupled to the originating exchange corresponding to the calling terminal and the home exchange where the called terminal is registered, through the telecommunication network, comprising of the steps of; receiving a call connection request signal from the originating exchange; corresponded to the received signal, transmitting a call connection request signal to the called terminal; routing the call to the home exchange, wherein the ringback tone substituting sound generator connected to the home exchange transmits the ringback tone substituting sound, through the established trunk connection, to the calling terminal.

[22] The present method may further comprise the steps of determining whether a called terminal is registered to the ringback tone replacement service or not, and routing the call to the home exchange if the called terminal is registered to the ringback tone replacement service. Further, the present method may further comprise the steps of transmitting a trunk connection release request to the home exchange when the called terminal answers in response to the call connection request, and releasing the trunk connection established between the ringback tone substitution sound generator and the calling terminal in response to the trunk connection release request. The ringback tone substituting sound generator extracts a ringback tone substituting sound selected by the subscriber which is corresponding to the called terminal from the database using the identifier of the called terminal, and transmits the selected sound to the called terminal. The identifier of the called terminal is the MIN (Mobile Identification Number). And, the trunk connection is established by the ISUP (Integrated Service Digital Network User Part) call setup.

[23] In accordance with another aspect of the present invention, there is provided a terminating exchange corresponding to the called terminal and being coupled to the originating exchange corresponding to the calling terminal and the home exchange where the called terminal is registered, through the telecommunication network, the terminating exchange comprising means for receiving a call connection request signal from the originating exchange, corresponded to the received signal, means for transmitting a call connection request signal to the called terminal, and means for routing the call to the home exchange, wherein the ringback tone substituting sound generator connected to the home exchange transmits the ringback tone substituting sound, through the established trunk connection, to the calling terminal.

[24] In accordance with yet another aspect of the present invention, there is provided a service provision apparatus for providing ringback tone substitution sound, the service provision apparatus corresponding to the terminating terminal and being coupled to the originating exchange corresponding to the calling terminal and the home exchange where the called terminal is registered, the service provision apparatus comprising memory for storing therein a program, and a processor connected to the memory to execute the program, wherein the processor is operated by the program so that it receives a call connection request signal from the originating exchange, corresponded to the received signal, transmits a call connection request signal to the called terminal, and routes the call to the home exchange, wherein the ringback tone substituting sound generator connected to the home exchange transmits the ringback tone substituting sound, through the established trunk connection, to the calling terminal.

Advantageous Effects

[25] According to the method of providing sounds for substituting ringback tones of the present invention, there is an advantage of reducing the cost tremendously because it can be used immediately with minimal modification of function of the existing terminating exchanges, such as making a branched call connection to the ringback tone substituting sound generator when the terminating exchange does paging to the called terminal, in the mobile communication network.

[26] According to the method of providing sounds for substituting ringback tones of the present invention, there is an advantage of reducing a volume of the database by connecting the each ringback tone substituting sound generator to the Home MSC/ VLR separately according to the subscribers.

[27] According to the method of providing sounds for substituting ringback tones of the present invention, there is an advantage of reducing a number of Point Codes, which are network resource of high cost, by assigning local Point Code when connecting to the terminating exchange. Brief Description of the Drawings

[28] Fig. 1, Fig.2, and Fig. 3 are simplified drawings of the exchange having a T-S-T

[29] Fig. 4 is a sequence diagram showing a signal flow in detail for offering ringback tone in accordance with the prior art.

[30] Fig. 5 is a simplified diagram showing a construction of a ringback tone replacement service according to a preferred embodiment of the present invention.

[31] Fig. 6 is a sequence diagram showing a process of providing ringback tone substituting sound using a Home MSC/VLR according to a preferred embodiment of the present invention.

[32] Fig. 7 is a simplified flowchart showing a procedure of providing ringback tone substituting sound according to a preferred embodiment of the present invention.

[33] Fig. 8 is a signal sequence diagram showing a procedure of connecting to the terminating MSC/VLR according to a preferred embodiment of the present invention.

[34] Fig. 9 is a signal sequence diagram showing a procedure of generating and providing ringback tone substituting sound according to a preferred embodiment of the present invention.

[35] Fig. 10 is a signal sequence diagram showing a procedure of changing to a normal call according to a preferred embodiment of the present invention.

[36] Fig. 11 is a simplified drawing showing distributed architecture of the system generating ringback tone substituting sound (iVSC) according to a preferred embodiment of the present invention. Best Mode for Carrying Out the Invention

[37] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[38] Fig. 5 is a simplified diagram showing a construction of a ringback tone replacement service according to a preferred embodiment of the present invention.

[39] The method for providing sounds for substituting ring-back tones according to a preferred embodiment of the present invention is described below simply with reference to Fig. 5. First, a caller requests a call to a called terminal 313 using a calling terminal 311, then the originating exchange 301 requests a call connection to the terminating exchange 303 after finding a location of the called terminal. At this time, while requesting a call connection to the called terminal 313, the terminating exchange 303 requests a call connection to the home exchange (it will be called as Home MSC/ VLR 305 hereinafter) using the information of the ringback tone replacement service to which the called party subscribed. That is, the terminating exchange 303 routes the call to the Home MSC/VLR 305 using the MEN information of the called terminal 313. The Home MSC/VLR 305 received the call routing request tries an ISUP call setup to the ringback tone substituting sound generator (it will be called as iVSC 307 hereinafter) connected to itself. After the ISUP call setup to the iVSC 307 is completed, the iVSC 307 extracts a ringback tone substituting sound stored in the database using the MIN of the calling terminal 311 and the called terminal 313, and transmits the selected sound, through the established trunk connection, to the calling terminal 311. Then, the terminating exchange 303 does paging to the called terminal 313, and transmits an ANM to the originating exchange 301 at the time it receives the result whether the connection is completed or failed. Thereafter, the terminating exchange 303 requests the Home MSC/VLR 305 to release the trunk connection established to the iSCV 307 for offering a ringback tone substituting sound. Finally, the Home MSC/VLR 305 releases the trunk connection established to the iSVC 307 in response to the request. After this procedure, the calling terminal can continue a normal call procedure with the called terminal.

[40] Fig. 6 is a sequence diagram showing a process of providing ringback tone substituting sound using a Home MSC/VLR according to a preferred embodiment of the present invention.

[41] Referring to Fig. 6, the originating MSC/VLR 301 transmits a LocReq (Location

Request) message to the HLR (Home Location Register 40 in order to inquire the location information of the called terminal at step 401. The HLR 40 returns a LocReq response message back to the originating MSC/VLR 301 in response to the received LocReq message. Thereafter, the originating MSC/VLR 301 transmits an IAM (Initial Address Message) message to the terminating MSC/VLR 303 using the returned LocReq response message at step 405.

[42] The terminating MSC/VLR 303 returns an ACM (Address Complete Message) to the originating MSC/VLR 301 in response to the received IAM at step 407, and transmits an IAM message to the Home MSC/VLR 305 connected through the network at step 409. At this time, the terminating MSC/VLR 303 determines whether the called party subscribed to the ringback tone replacement service or not by querying the database using the called terminal s MIN, and if subscribed, transmits an IAM message (call connection request) to the Home MSC/VLR 305.

[43] Home MSC/VLR 305 requests a call connection (transmitting IAM message) to the connected iVSC 307 at step 411. It means that Home MSC/VLR 305 tries an ISUP call setup to the connected the iVSC 307. The iVSC 307 transmits an ACM message to the Home MSC/VLR in response to the received ISUP call setup request at step 413. The Home MSC/VLR 305 received the ACM message from the connected iVSC 307 also transmits an ACM to the terminating MSC/VLR 303.

[44] The iVSC 307 transmits an ANM (Answer Message) to the Home MSC/VLR 305 in response to the ISUP call setup, and then the ANM message is transmitted to the terminating MSC/VLR 303 at steps of 417 and 419. The ISUP call setup from the calling terminal to the iVSC 307 is completed at step 421 when the terminating MSC/ VLR 303 receives the ANM.

[45] Then, the terminating MSC/VLR 303 does paging to the called terminal, and transmits an ANM to the originating MSC/VLR 301 at the time it receives the result whether the connection is completed or failed. Thereafter, the terminating MSC/VLR 303 transmits a REL message to the Home MSC/VLR 305 in order to release the trunk connection established to the iVSC 307 for offering a ringback tone substituting sound, and the Home MSC/VLR 305 forwards the REL to the iVSC 307. The iVSC 307 transmits a RLC message to the Home MSC/VLR 305 in response to the received REL, and the Home MSC/VLR 305 forwards it to the terminating MSC/VLR 303 at steps of 425, 427,429 and 431. Through the above-described process, the trunk connection established to the iVSC 307 for offering a ringback tone substituting sound is released. Thereafter, at step 433, the calling terminal can continue a normal call procedure with the called terminal.

[46] Through the above-described process, the ringback tone substituting sound can be provided easily to the calling terminal using the Home MSC/VLR 305 and the connected iVSC 307 wherever the called terminal is located. The above-described process will be described in detail with references to the attached drawings.

[47] Fig. 7 is a simplified flowchart showing a procedure of providing ringback tone substituting sound according to a preferred embodiment of the present invention.

[48]

[49] Referring to Fig. 7, the method for providing sounds for substituting ring-back tones comprises the steps of finding the location of the called terminal (step 501), connecting to the terminating MSC/VLR 303 (step 503), creating and offering a ringback tone substituting sound (step 505), and changing to a normal call procedure (step 507).

[50] The first step of finding the location of the called terminal is a process of getting the location of the called terminal from the HLR in the mobile communication network. This step is identical to one of Fig. 6, so that a detailed description thereof is omitted.

[51] Second, the step of connecting to the terminating MSC/VLR 303 (step 503) will be described in detail with reference to the Fig. 8.

[52] Fig. 8 is a signal sequence diagram showing a procedure of connecting to the terminating MSC/VLR according to a preferred embodiment of the present invention.

[53] Referring to Fig. 8, the originating MSC/VLR 301 requests a call connection to the terminating MSC/VLR 303 using the LocReq message returned from the HLR 40 at step 601. In detail, the originating exchange 301 requests the call connection by transmitting an IAM (Initial Address Message) to the terminating MSC/VLR 303. The terminating MSC/VLR 303 returns an acknowledge message, ACM (Address Complete Message), to the originating MSC/VLR 301 in response to the call connection request from the originating MSC/VLR 301, and requests a call connection to the called terminal 60 located in the area it covers at step 603.

[54] At this time, the terminating MSC/VLR 303 can determine whether the called party subscribed the ringback tone replacement service or not, and if subscribed, the process moves to the next step.

[55] In the prior art, during the above-described process, the terminating MSC/VLR 303 transmits an ACM to the originating MSC/VLR 301, requests a call connection to the called terminal, and then transmits a ringback tone to the calling terminal by the ITU-T specification depending on the status of the called terminal until the trunk connection is established. However, in the present invention, instead of transmitting a ringback tone to the calling terminal by itself, the terminating MSC/VLR 303 requests a call connection to the Home MSC/VLR, which is connected through the telecommunication network, at the state of it requested a call connection to the called terminal. The ringback tone replacement service model according to a preferred embodiment of the present invention can be provided as the iVSC connected to the Home MSC/VLR transmits a ringback tone substituting sound to the called terminal.

[56] Referring to Fig. 7, the step of creating and offering a ringback tone substituting sound (step 505) will be described in detail with reference to Fig. 9.

[57] Fig. 9 is a signal sequence diagram showing a procedure of generating and providing ringback tone substituting sound according to a preferred embodiment of the present invention.

[58] Referring to Fig. 9, the terminating MSC/VLR 303 determines whether the called party subscribed to the ringback tone replacement service or not, at step 701. That is, the terminating MSC/VLR 303 can determine whether the called party subscribed to the ringback tone replacement service or not by querying the database using the called terminal s MIN. If the called party subscribed, the terminating MSC/VLR 303 routes the call to the Home MSC/VLR 305 using MIN at step 703. Corresponded to the call routing, the Home MSC/VLR 305 tries an ISUP call setup to the connected iVSC 307 at step 705. After the ISUP call setup to the iVSC 307 is completed, the iVSC 307 extracts a ringback tone substituting sound stored in the database using the MIN of the calling terminal and the called terminal at step 707. Thereafter, the iVSC 307 transmits the selected sound, through the established trunk connection, to the calling terminal at step 709.

[59] Referring to Fig. 7, the step of changing to a normal call procedure (step 507) will be described in detail with reference to Fig. 10.

[60] Fig. 10 is a signal sequence diagram showing a procedure of changing to a normal call according to a preferred embodiment of the present invention.

[61] Referring Fig. 10, the terminating MSC/VLR 303 transmits an ISUP message,

ANM, to the originating MSC/VLR 301 at the time it receives the result whether the connection is completed or failed after it requests a call connection to the called terminal at step 801. Thereafter, the terminating MSC/VLR 303 transmits a REL message to the Home MSC/VLR 305 in order to release the trunk connection established to the iVSC 307 for offering a ringback tone substituting sound at step 803. The Home MSC/VLR 305 also releases the established trunk connection by forwarding the REL to the iVSC 307 at step 805.

[62] The following is identical to a normal voice call processing, so that a detailed description thereof is omitted.

[63]

[64] In order to implement the above-described method for providing sounds for substituting ringback tones of the present invention, it is possible to make a configuration of the terminating MSC/VLR and iVSC using El trunk and SS7 signaling similar to the one of the VMS (Voice Messaging System). Moreover, it is possible to implement the service registration field for a ringback tone replacement service to be registered in the HLR and the VLR (Visited Location Register) similar to the VMS s. However, the trunk connection between the terminating MSC/VLR and the Home MSC/VLR is required for the call transfer in the present invention whereas it is not required when the call is transferred to the VMS. Moreover, the Home MSC/VLR can be connected to the iVSC using the call information defined in the IAM message. To adopt the process of querying the information related with the HLR and VLR defined in the IS-41C or IS-41D standard specification, a 'Special Route Sequence' can be used for the terminating exchanges to route the call to the Home MSC/VLR.

[65] It is necessary to distribute the apparatuses regionally for providing sounds for substituting ringback tones of the present invention in order to interface them to the current telecommunication network. In a mobile communication network, a subscriber can move to other places, in this case, it is possible to distribute the iVSCs regionally to adopt the apparatus for providing sounds for substituting ringback tones of the present invention. This will be described in detail with reference to the Fig. 11.

[66] Fig. 11 is a simplified drawing showing distributed architecture of the system generating ringback tone substituting sound (iVSC) according to a preferred embodiment of the present invention.

[67] Referring to Fig. 11, the subscriber information including the ringback tone substituting sound of the subscriber is stored in the iVSC of the present invention.

[68] The subscriber information can be stored in the central database for ringback tone substituting sounds as redundancy to cope with the iVSC s fault. The ringback tone substituting sounds stored in the central database are used only for backup for the ringback tone replacement service of present invention actually the ringback tone substituting sounds stored in the iVSC are used in service. Through the above-described process, a real time ringback tone replacement service can be provided. Moreover, the quality of the service can be guaranteed as each iVSC only manages the database and provides the service within the subscribers allocated to it.

[69] Home MSC/VLR information of the new subscribers can be saved in the HLR after interfacing new iVSC with the network by allocating subscribers to the certain iVSC in order to adopt the situation that subscribers are increased in the future. Through the above-described process, a large number of new subscribers can be adopted without lots of modification of the system, and the ringback tone substituting sound can be provided with only the Home MSC/VLR and the connected iVSC that are assigned to the subscriber even through the subscriber moves to the another area. It means that extending database capability infinitely is not necessary.

[70] The present invention is not limited to the embodiments, and those skilled in the art will appreciate that various modifications are possible, without departing from the spirit of the invention.

[71]

Claims

[1] The method, conducted by the terminating exchange, for providing sounds for substituting ringback tones by the terminating exchange corresponding to the called terminal and being coupled to the originating exchange corresponding to the calling terminal, the home exchange where the called terminal is registered, and the ringback tone substituting sound generator, through the telecommunication network, comprising of the steps of; receiving a call connection request signal from the originating exchange; corresponded to the received signal, transmitting a call connection request signal to the called terminal; and transmitting the call connection request signal to the home exchange wherein the call connection request signal includes the identifier of the called terminal, wherein corresponded to the signal received from the terminating exchange, the home exchange transmits a call connection request signal to the ringback tone substituting sound generator, and the ringback tone substituting sound generator extracts a ringback tone substituting sound for the called terminal and transmits the selected sound, through the established trunk connection, to the calling terminal.

[2] The method, conducted by the terminating exchange, for providing sounds for substituting ringback tones according to the claim 1, further comprising the step of determining whether a called terminal is registered to the ringback tone replacement service or not, wherein the terminating exchange routes the call to the home exchange if the called terminal is registered to the ringback tone replacement service.

[3] The method, conducted by the terminating exchange, for providing sounds for substituting ringback tones according to the claim 1, further comprising the step of transmitting a trunk connection release request to the home exchange when the called terminal answers in response to the call connection request, wherein the trunk connection established between the ringback tone substitution sound generator and the calling terminal is released in response to the trunk connection release request.

[4] The method, conducted by the terminating exchange, for providing sounds for substituting ringback tones according to the claim 1, wherein the ringback tone substituting sound generator extracts a ringback tone substituting sound selected by the subscriber which is corresponding to the called terminal from the database using the identifier of the called terminal, and transmits the selected sound to the called terminal.

[5] The method, conducted by the terminating exchange, for providing sounds for substituting ringback tones according to the claim 4, wherein the identifier of the called terminal is the MIN (Mobile Identification Number).

[6] The method, conducted by the terminating exchange, for providing sounds for substituting ringback tones according to the claim 1, wherein the trunk connection is established by the ISUP (Integrated Service Digital Network User Part) call setup.

[7] The terminating exchange for providing a ringback tone replacement service, the terminating exchange corresponding to the called terminal and being coupled to the originating exchange corresponding to the calling terminal, the home exchange where the called terminal is registered, and the ringback tone substituting sound generator, through the telecommunication network, comprising; means for receiving a call connection request signal from the originating exchange; means for transmitting a call connection request signal to the called terminal, corresponded to the received signal; and means for transmitting the call connection request signal to the home exchange wherein the call connection request signal includes the identifier of the called terminal, wherein corresponded to the signal received from the terminating exchange, the home exchange transmits a call connection request signal to the ringback tone substituting sound generator, and the ringback tone substituting sound generator extracts a ringback tone substituting sound for the called terminal and transmits the selected sound, through the established trunk connection, to the calling terminal.

[8] The terminating exchange for providing a ringback tone replacement service, the terminating exchange corresponding to the called terminal and being coupled to the originating exchange corresponding to the calling terminal, the home exchange where the called terminal is registered, and the ringback tone substituting sound generator, through the telecommunication network, comprising memory for storing therein a program; and a processor connected to the memory to execute the program, wherein the processor is operated by the program so that it receives a call connection request signal from the originating exchange, corresponded to the received signal, transmits a call connection request signal to the called terminal, and transmitting the call connection request signal to the home exchange wherein the call connection request signal includes the identifier of the called terminal, wherein corresponded to the signal received from the terminating exchange, the home exchange transmits a call connection request signal to the ringback tone substituting sound generator, and the ringback tone substituting sound generator extracts a ringback tone substituting sound for the called terminal and transmits the selected sound, through the established trunk connection, to the calling terminal.