JP7498920B1 - Telephone number investigation device, investigation method, investigation program, and information provision system - Google Patents

Abstract

[Problem] The usage status of telephone numbers in an IMS network is determined by utilizing an IMS interconnection interface or the like for interconnection between carriers. [Solution] A telephone number investigation device 10 is connected to a plurality of IMS terminals 50 connected to a terminating mobile IMS network 30 via an originating fixed IMS network 20, and sends an INVITE request to the originating fixed IMS network 20 by adding SDP parameters to the INVITE request for the IMS terminal 50 to be investigated, and receives a response message via the originating fixed IMS network 20, and determines the usage status of the telephone number of the IMS terminal 50 to be investigated according to the response message. [Selected Figure] Figure 1

Description

The present invention relates to a technology for investigating telephone numbers.

A known prior art for determining telephone number information is a telephone number information determination device using a computer server connected to multiple terminals via an Internet network, which includes a database that stores usage history information for multiple telephone numbers, search information receiving means that receives authentication information from the terminal and receives telephone numbers as search information from the terminal on the condition that the authentication means allows login, and a system control means that searches the database using the telephone number received by the search information receiving means, analyzes the change in the telephone number field to a missing number to see if there are multiple histories in the telephone number history information that transition from a subscription state to a missing number state, and/or analyzes the valid change in the telephone number field to see if there are multiple histories in the telephone number history information that transition from a missing number state to a subscription state, and generates history determination information that determines the telephone number in the search information to be a specified subscriber number by referring to unaccumulated history in the telephone number history information, the most recent investigation record in the telephone number history information that is a missing number history, the investigation record one record before the most recent investigation record that is a missing number history, and multiple call stop histories in the telephone number history information, and displays this history determination information on the terminal via the Internet network (see Patent Document 1).

JP 2014-060796 A

By the way, with the transition from PSTN (Public Switched Telephone Networks) to NGN (Next Generation Network), the interconnection interface between operators will also be changed from SS7 (Signaling System No. 7), a common channel signaling system, to SIP (Session Initiation Protocol), an IP (Internet Protocol). As a result, a specific SIP message from a calling terminal (for example, a telephone number research device) will reach the IMS (IP Multimedia Subsystem) network, the NGN network, and the IP telephone network (VoIP: Voice over Internet Protocol).

IMS is a standard for converting services that have previously been provided via fixed networks and mobile communications into IP, and realizing integrated multimedia services. Mobile communications systems and NGN are examples of systems built in accordance with this standard.

For this reason, it is necessary to introduce a SIP protocol-based telephone number investigation tool that can connect to the originating IMS network via a UNI (User Network Interface), using an IMS interconnection interface for interconnection between operators and determining the usage status of telephone numbers in the destination IMS network, in order to ensure a smooth transition to the new system infrastructure.

In one aspect, the present invention aims to provide a technology that can determine the usage status of telephone numbers in an IMS network by using an IMS interconnection interface or the like for interconnection between carriers.

In order to solve the above problem, the telephone number investigation device according to the present invention is a telephone number investigation device connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network, and includes a message exchange control unit that adds SDP parameters to an INVITE request for the IMS terminal to be investigated, transmits the INVITE request to the originating fixed IMS network, and receives a response message via the originating fixed IMS network, and a telephone number investigation determination unit that determines the usage status of the telephone number of the IMS terminal to be investigated according to the response message, and the SDP parameters may be described as: network protocol is IPv4, media type is audio only, media transport protocol is RTP/AVP only, and voice codec includes G.711 μ-law and G.722.

The telephone number investigation device according to the present invention may be configured such that the telephone number investigation determination unit determines that the telephone number of the IMS terminal being investigated actually exists if the response message is code 183 Session Progress, code 180 Ringing, code 487 Request Terminated, code 488 Not Acceptable Here, code 500 Server Internal Error, or code 486 Busy Here, and determines that the telephone number of the IMS terminal being investigated is a missing number if the response message is code 404 Not Found.

The telephone number investigation device according to the present invention may be configured such that, when the response message is code 183 Session Progress or code 180 Ringing, the telephone number investigation determination unit determines that the telephone number of the IMS terminal being investigated is real, and the message exchange control unit sends a CANCEL request to the originating fixed IMS network, thereby stopping the ringing of the call bell of the IMS terminal being investigated if the anonymous call rejection service and anonymous call rejection function are not set for the IMS terminal being investigated.

The telephone number survey method according to the present invention is a telephone number survey method for surveying the usage status of telephone numbers of IMS terminals to be surveyed using a device connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network, and includes the steps of: sending an INVITE request to the IMS terminal to be surveyed by the device with SDP parameters; receiving a response message via the originating fixed IMS network; and determining the usage status of the telephone number of the IMS terminal to be surveyed according to the response message; and the SDP parameters may be described as: network protocol is IPv4; media type is audio only; media transport protocol is RTP/AVP only; and voice codec includes G.711 μ-law and G.722.

The telephone number investigation method according to the present invention is a telephone number investigation method for investigating the usage status of the telephone number of the IMS terminal to be investigated using a device connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network, and includes the steps of the device adding SDP parameters to an INVITE request for the IMS terminal to be investigated and sending the INVITE request to the originating fixed IMS network, receiving a response message via the originating fixed IMS network, and determining the usage status of the telephone number of the IMS terminal to be investigated according to the response message, and the SDP parameters may be described as the network protocol being IPv6, the media type being audio only, the media transport protocol being RTP/AVP only, and the voice codec being G.711 μ-law only.

The telephone number investigation method according to the present invention may determine that the telephone number of the IMS terminal being investigated actually exists if the response message is code 183 Session Progress, code 180 Ringing, code 487 Request Terminated, code 488 Not Acceptable Here, code 500 Server Internal Error, or code 486 Busy Here, and determine that the telephone number of the IMS terminal being investigated is a missing number if the response message is code 404 Not Found.

The telephone number investigation method according to the present invention may determine that the telephone number of the IMS terminal being investigated exists when the response message is code 183 Session Progress or code 180 Ringing, and send a CANCEL request to the originating fixed IMS network, thereby stopping the ringing of the call bell of the IMS terminal being investigated when the anonymous call rejection service and anonymous call rejection function are not set for the IMS terminal being investigated.

The telephone number survey program of the present invention may execute at least the following processes on a computer connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network: adding SDP parameters to an INVITE request for the IMS terminal to be surveyed and sending the INVITE request to the originating fixed IMS network; receiving a response message via the originating fixed IMS network; and determining the usage status of the telephone number of the IMS terminal to be surveyed according to the response message, and the SDP parameters may be described as: network protocol is IPv4, media type is audio only, media transport protocol is RTP/AVP only, and voice codec includes G.711 μ-law and G.722.

The telephone number investigation program of the present invention may determine that the telephone number of the IMS terminal being investigated actually exists if the response message is code 183 Session Progress, code 180 Ringing, code 487 Request Terminated, code 488 Not Acceptable Here, code 500 Server Internal Error, or code 486 Busy Here, and may determine that the telephone number of the IMS terminal being investigated is a missing number if the response message is code 404 Not Found.

The telephone number investigation program according to the present invention may determine that the telephone number of the IMS terminal being investigated is real if the response message is code 183 Session Progress or code 180 Ringing, and send a CANCEL request to the originating fixed IMS network, thereby stopping the ringing of the call bell of the IMS terminal being investigated if the anonymous call rejection service and anonymous call rejection function are not set for the IMS terminal being investigated.

The telephone number information provision system according to the present invention may also include any one of the telephone number investigation devices described above and a user terminal, and may include a network interface unit that, when the telephone number investigation device receives a telephone number investigation information provision request for the IMS terminal from the user terminal, transmits the telephone number usage status of the IMS terminal determined by the telephone number investigation determination unit to the user terminal that has made the telephone number investigation information provision request via an IP network.

According to one aspect of the present invention, it is possible to determine the usage status of telephone numbers in an IMS network by using an IMS interconnection interface or the like for interconnection between carriers.

1 is a schematic diagram showing a network connection form of a telephone number research device according to an embodiment of the present invention; FIG. 10 is a diagram for explaining a basic sequence pattern 1 of the operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 10 is a diagram for explaining pattern 2 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 11 is a diagram for explaining pattern 3 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 11 is a diagram illustrating pattern 4 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 11 is a diagram for explaining a basic sequence pattern 5 of the operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 11 is a diagram for explaining a basic sequence pattern 6 of the operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 11 is a diagram for explaining a basic sequence pattern 7 of the operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 11 is a diagram for explaining a basic sequence pattern 8 of the operation between the calling device, the calling fixed IMS network, and the called mobile IMS network when a mobile phone is actually present as the called device and is not busy. FIG. 1 is a diagram for explaining a basic sequence pattern 1 of an operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as a called device and is busy. FIG. 10 is a diagram for explaining pattern 2 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a mobile phone is actually present as the called device and is busy. A diagram explaining the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when the called device has an unused number. FIG. 2 is a block diagram showing the configuration of the telephone number investigation device of FIG. 1. FIG. 10 is a diagram illustrating a first operational sequence when a mobile phone actually exists as an IMS terminal to be investigated and is not busy. FIG. 11 is a diagram illustrating a second operational sequence when a mobile phone actually exists as the IMS terminal to be investigated and is not busy. FIG. 11 is a diagram illustrating the third operational sequence when a mobile phone actually exists as the IMS terminal to be investigated and is not busy. FIG. 10 is a diagram for explaining a first operational sequence when a mobile phone actually exists as the IMS terminal to be surveyed and is busy. FIG. 11 is a diagram illustrating a second operational sequence when a mobile phone actually exists as the IMS terminal to be surveyed and is busy. 11 is a diagram illustrating an operation sequence when an IMS terminal to be investigated has a missing number. FIG. FIG. 13 is a diagram for explaining an operation sequence when the IMS terminal to be investigated has a missing number (IPv4, G.711 μ-law only). FIG. 10 is a diagram for explaining a basic sequence pattern 1 of an operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a data communication-only terminal actually exists as a called device. 13 is a diagram for explaining a basic sequence pattern 2 of the operation between a calling device, a calling fixed IMS network, and a called mobile IMS network when a data communication-only terminal actually exists as a called device. FIG. A diagram explaining pattern 3 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a data communication-only terminal actually exists as the called device. FIG. 11 is a diagram for explaining pattern 4 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a data communication-only terminal actually exists as the called device. A diagram explaining pattern 5 of the basic sequence of operations between a calling device, a calling fixed IMS network, and a called mobile IMS network when a data communication-only terminal actually exists as a called device. FIG. 10 is a diagram for explaining a first operation sequence in the case where a data communication-only terminal actually exists as the IMS terminal to be investigated. FIG. 11 is a diagram for explaining a second operation sequence in the case where a data communication-only terminal actually exists as the IMS terminal to be investigated. FIG. 11 is a diagram for explaining the third basic sequence in the case where a data communication-only terminal actually exists as the IMS terminal to be investigated. FIG. 4 is a diagram for explaining the fourth basic sequence in the case where a data communication-only terminal actually exists as the IMS terminal to be investigated. FIG. 5 is a diagram for explaining the fifth basic sequence in the case where a data communication-only terminal actually exists as the IMS terminal to be investigated. FIG. 1 is a diagram showing a method for investigating the usage status of a telephone number of an IMS terminal. 1 is a system configuration diagram of a telephone number information providing system according to an embodiment of the present invention;

The following describes an embodiment of the present invention with reference to the attached drawings.

(Network connection form)
FIG. 1 is a schematic diagram showing a network connection form of a telephone number investigation device 10 according to an embodiment, as an example of a specific configuration mode of the telephone number investigation device according to the present invention.

The telephone number investigation device 10 according to the embodiment is connected to a plurality of mobile phone terminals (specifically, IMS terminals 50a, 50b, 50c) to be investigated, which are connected to a receiving mobile IMS network 30 (specifically, for example, an IP telephone network (VoIP: Voice over Internet Protocol)) via a calling fixed IMS network 20 (specifically, for example, an NGN network). In the explanation of the embodiment, when it is not necessary to distinguish between the IMS terminals 50a, 50b, 50c for each network (in other words, for each contract carrier or contract business), they will simply be referred to as "IMS terminals 50".

The originating fixed IMS network 20 is equipped with a SIP server 20a, and the operation of the originating fixed IMS network 20 is managed and controlled by the SIP server 20a. The terminating mobile IMS network 30 is equipped with SIP servers 30a, 30b, and 30c, and the operation of the terminating mobile IMS network 30 is managed and controlled by the SIP servers 30a, 30b, and 30c.

The terminating mobile IMS network 30 is constructed for each telecommunications carrier (in the example shown in FIG. 1, carrier A, carrier B, and carrier C), and IMS terminals 50a, 50b, and 50c are connected to each network (in other words, each contracted carrier or each contracted business operator) via SIP servers 30a, 30b, and 30c managed and operated by each of them.

The destination mobile IMS network 30 supports at least the IP (Internet Protocol) v4 network protocol (in other words, the Internet Protocol, IP version) for SDP (Session Description Protocol) parameters, supports audio as a media type, supports RTP/AVP as a media transport protocol, and requires G.711 μ-law as a voice codec.

The IMS terminal 50 is assumed to be a mobile phone (mobile terminal) with a 0A0 type (specifically, for example, 090, 080, and 070) telephone number or a terminal dedicated to data communication, and is connected to the terminating mobile IMS network 30, which is the network on the receiving side.

In the configuration shown in FIG. 1, the telephone number investigation device 10, which is the calling device, dials the telephone numbers of the IMS terminals 50a, 50b, and 50c connected to the called mobile IMS network 30 as the telephone numbers of the called telephone terminals, and routing is performed in the order of the SIP server 20a in the calling fixed IMS network 20, the calling IBCF (Inter-connection Border Control Function) 21, the called IBCF 31, the SIP servers 30a, 30b, and 30c, and the called IMS terminals 50a, 50b, and 50c. In the telephone number investigation method according to the present invention, as described below, the telephone number investigation device 10, which is the calling device, sets the calling number to be withheld (specifically, adds the number "184" before the telephone number of the called party), and transmits the telephone number.

At this time, a UNI connection is guaranteed between the telephone number investigation device 10 and the originating fixed IMS network 20, and the inter-operator interconnection between the originating fixed IMS network 20 and the terminating mobile IMS network 30 is guaranteed via an IMS interconnection interface (specifically, the originating IBCF 21 and the terminating IBCF 31), and a specific SIP message (details will be described later) sent from the telephone number investigation device 10 in accordance with the SIP signaling method reaches the terminating mobile IMS network 30.

In the example shown in Figure 1, the NNI (Network-Network Interface), which is a common interface for interconnection between IMS operators via IP-IP connections, is specified in the TTC standard JJ-90.30 (TTC: Telecommunication Technology Committee).

According to SIP, in order to carry out real-time communication, it is necessary for terminals to negotiate the encoding method of packets containing media information and the addresses of the packet destinations, etc. This negotiation requires a description language called SDP (Session Description Protocol), which is defined in the TTC standard RFC4566.

To establish a session with SIP, the calling party first sends a request that describes media information in a SIP message, and the called party replies with a response in which it selects compatible media from that request, thereby sharing the media information to be used for communication between the calling party and the called party.

Sending a SIP message with media information to start a session is called an offer, and returning compatible media information in response is called an answer. This offer/answer model is defined in the TTC standard RFC3264. Furthermore, the SDP media negotiation procedure in IMS is specified in the TTC standard JJ-90.26.

In the example shown in FIG. 1, when the telephone number investigation device 10 sends an SDP offer (called an "INVITE request") of the INVITE method to the IMS terminal 50 to be investigated via the calling fixed IMS network 20 (including SIP server 20a) and the called mobile IMS network 30 (including SIP servers 30a, 30b, and 30c), it adds (in other words, writes) a specific SDP parameter (called an "SDP parameter for determination") to the SDP parameter and transmits it.

The SDP parameters added to the SDP parameters when sending an INVITE request are the network protocol (in other words, the Internet Protocol, IP version), media type, media transport protocol, and audio codec.

In response to an INVITE request, the IMS terminal 50 on the receiving side compares the SDP parameters included in the INVITE request with the SDP parameters that it can use, and depending on the result of the comparison (i.e., whether the SDP parameters match or mismatch), returns a response with a specified code in the SIP session as a response message.

Then, the telephone number investigation device 10 determines whether the receiving IMS terminal 50 exists or does not exist (and thus whether the telephone number of the IMS terminal 50 exists or is missing) based on the received response of the specified code.

(Basic sequence)
2 to 12 are diagrams for explaining a basic sequence of operations between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30 when the IMS terminal 50 as the called device is a mobile phone by the INVITE method in IMS interconnection. Note that the basic sequence of operations between the calling device (specifically, the telephone number investigation device 10) according to the embodiment and the IMS terminal 50 which is a mobile phone is not limited to the contents shown in Figs. 2 to 12, and may be in accordance with, for example, the contents specified in TTC standard JJ-90.30, TTC standard JJ-90.26, TTC standard JF-IETF-RFC3398, TTC standard TR-1088, TTC standard JT-Q850, and TTC specification TS-1025.

Communication is carried out between the calling device and the called device (specifically, a mobile phone) connected to the called mobile IMS 30 via the calling fixed IMS network 20, the calling IBCF 21, the called IBCF 31, and the called mobile IMS network 30.

(In the real world / Pattern 1)
FIG. 2 is a diagram for explaining a basic sequence pattern 1 of the operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 2 is a diagram explaining the basic sequence when there is no setting to reject incoming calls, particularly when the caller has set the phone number to be withheld. Here, there are two ways to set up the setting to reject incoming calls: using a service provided by a carrier (communications operator) (called the "withheld call rejection service"), or using a function provided in the IMS terminal 50 itself (called the "withheld call rejection function"). In other words, Figure 2 is a diagram explaining the basic sequence when the withheld call rejection service and withheld call rejection function are not set.

The calling device sends an INVITE request to the called device via the calling fixed IMS network 20 and the called mobile IMS network 30, such as the mobile phone network of the called device's contract carrier (F1). In response, an INVITE request is sent from the calling fixed IMS network 20 to the called mobile IMS network 30 (F2).

In response to this, the terminating mobile IMS network 30 returns a code 100 Trying response to the originating fixed IMS network 20 indicating that the request has been accepted in the SIP session (F3), and in response to this, the originating fixed IMS network 20 returns a code 100 Trying response to the calling device (F4).

Then, the terminating mobile IMS network 30 returns a code 183 Session Progress response indicating the progress of the call in the SIP session to the originating fixed IMS network 20 (F5), and in response, the originating fixed IMS network 20 returns a code 183 Session Progress response to the calling device (F6).

At this time, the receiving device (specifically, the mobile phone) rings, and an RBT (Ringing Back Tone) is sent as RTP (Real time Transport Protocol) from the receiving mobile IMS network 30 to the calling device via the originating fixed IMS network 20 (F7).

Next, a code 200 OK response is returned from the terminating mobile IMS network 30 to the originating fixed IMS network 20, indicating that the request in the SIP session (specifically, the INVITE request and confirmation of SDP information) has been successfully processed (F8), and in response, a code 200 OK response is returned from the originating fixed IMS network 20 to the calling device (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11). Then, a session is established between the calling device and the called device, and communication (a call) is started.

After that, (in the example shown in FIG. 2, when the calling device disconnects the communication) a BYE request indicating the end of the SIP session is sent from the calling device to the calling fixed IMS network 20 (F12), and in response, a BYE request is sent from the calling fixed IMS network 20 to the called mobile IMS network 30 (F13).

In response to this (in the example shown in FIG. 2), the terminating mobile IMS network 30 returns a code 200 OK response to the originating fixed IMS network 20 indicating that the request (specifically, a BYE request) has been successfully processed in the SIP session (F14), and in response, the originating fixed IMS network 20 returns a code 200 OK response to the originating device (F15). This ends the session between the originating device and the terminating device, i.e., the communication (call) between the originating device and the terminating device is disconnected.

(In the real world / Pattern 2)
FIG. 3 is a diagram for explaining a basic sequence pattern 2 of the operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 3 is a diagram that explains the basic sequence when, like Figure 2, the anonymous call rejection service is not set and the anonymous call rejection function is not set. Note that the basic sequence pattern 1 shown in Figure 2 and the basic sequence pattern 2 shown in Figure 3 may differ in content due to the fact that the basic sequence may differ depending on, for example, the contracted carrier of the IMS terminal 50.

The operations F1 to F7 in pattern 2 of the basic sequence shown in Figure 3 are the same as the operations F1 to F7 in pattern 1 of the basic sequence shown in Figure 2.

In the basic sequence pattern 2 shown in FIG. 3, an RBT (Ringing Back Tone) is sent as an RTP (Real time Transport Protocol) from the terminating mobile IMS network 30 to the originating fixed IMS network 20 via the originating fixed IMS network 20 to the originating device (F7), and a code 180 Ringing response indicating that a ringtone is ringing in the SIP session is returned from the terminating mobile IMS network 30 to the originating fixed IMS network 20 (F8). In response to this, a code 180 Ringing response is returned from the originating fixed IMS network 20 to the originating device (F9).

In the basic sequence pattern 2 shown in FIG. 3, the operations of F10 to F17 after the code 180 Ringing response is returned (F8, F9) are the same as the operations of F8 to F15 in the basic sequence pattern 1 shown in FIG. 2. Then, the session between the calling device and the called device ends, that is, the communication (call) between the calling device and the called device is disconnected.

(In the real world / Pattern 3)
FIG. 4 is a diagram for explaining a basic sequence pattern 3 of an operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 4 is a diagram that explains the basic sequence when (at least) the anonymous call rejection service is set for the receiving device (i.e., mobile phone) and the calling device is set to anonymous caller number (specifically, the number "184" is added before the called party's phone number) and makes a call.

The operations F1 to F6 in pattern 3 of the basic sequence shown in Figure 4 are the same as the operations F1 to F6 in pattern 1 of the basic sequence shown in Figure 2.

In the basic sequence pattern 3 shown in FIG. 4, a code 183 Session Progress response is returned from the terminating mobile IMS network 30 to the calling device via the originating fixed IMS network 20 (F5, F6), and an incoming call rejection guidance is sent as RTP (Real time Transport Protocol) (F7) to inform the calling device that the incoming call has been rejected because the caller has set their phone number to be withheld. At this time, the calling device does not ring (because the incoming call has been rejected), and no call history is left on the called device.

Next, the terminating mobile IMS network 30 returns a code 200 OK response to the originating fixed IMS network 20 (F8) indicating that the request in the SIP session (specifically, the INVITE request and confirmation of SDP information) has been successfully processed (however, the incoming call is actually rejected), and in response, the originating fixed IMS network 20 returns a code 200 OK response to the calling device (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11).

After that, (when the calling device receives the call rejection guidance and disconnects the communication) a BYE request indicating the end of the SIP session is sent from the calling device to the calling fixed IMS network 20 (F12), and in response, a BYE request is sent from the calling fixed IMS network 20 to the called mobile IMS network 30 (F13).

In response to this, the terminating mobile IMS network 30 returns a code 200 OK response to the originating fixed IMS network 20 indicating that the request (specifically, a BYE request) has been successfully processed in the SIP session (F14), and in response, the originating fixed IMS network 20 returns a code 200 OK response to the originating device (F15). This ends the session between the originating device and the terminating device, i.e., the communication (call) between the originating device and the terminating device is disconnected.

(In the real world / Pattern 4)
FIG. 5 is a diagram illustrating a basic sequence pattern 4 of an operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 5 is a diagram explaining the basic sequence when (at least) the anonymous call rejection service is set for the receiving device (i.e., mobile phone) and the calling device is set to anonymous caller number (specifically, by adding the number "184" before the called party's telephone number) and makes a call. Note that the basic sequence pattern 3 shown in Figure 4 and the basic sequence pattern 4 shown in Figure 5 may differ depending on the contracted carrier of the IMS terminal 50, for example, and the contents are different due to this.

The operations F1 to F6 in basic sequence pattern 4 shown in Figure 5 are the same as the operations F1 to F6 in basic sequence pattern 1 shown in Figure 2.

In the basic sequence pattern 4 shown in FIG. 5, a code 183 Session Progress response is returned from the terminating mobile IMS network 30 to the calling device via the originating fixed IMS network 20 (F5, F6), and an incoming call rejection guidance is sent as RTP (Real time Transport Protocol) (F7) to inform the calling device that the incoming call has been rejected because the caller has set their phone number to be withheld. At this time, the calling device does not ring (because the incoming call has been rejected), and no call history is left on the called device.

Next, the terminating mobile IMS network 30 returns a code 433 Anonymous Disallowed response to the originating fixed IMS network 20, indicating that anonymity is not permitted on the terminating device in the SIP session (F8), and in response, the originating fixed IMS network 20 returns a code 433 Anonymous Disallowed response to the originating device (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11).

Then, the session related to the INVITE request from the calling device ends.

(In the real world / Pattern 5)
FIG. 6 is a diagram illustrating a basic sequence pattern 5 of an operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 6 is a diagram that explains the basic sequence when the anonymous call rejection function is set for the receiving device (i.e., a mobile phone) (and the anonymous call rejection service is not set), and the calling device is set to anonymous caller ID (specifically, the number "184" is added before the called party's phone number) and makes a call.

The operations F1 to F6 in basic sequence pattern 5 shown in FIG. 6 are the same as the operations F1 to F6 in basic sequence pattern 1 shown in FIG. 2.

In the basic sequence pattern 5 shown in FIG. 6, the terminating mobile IMS network 30 returns a code 183 Session Progress response to the calling device via the originating fixed IMS network 20 (F5, F6), and an RBT (Ringing Back Tone) is sent as an RTP (Real time Transport Protocol) (F7). At this time, the calling device does not ring (because the incoming call has been rejected), and the incoming call history remains on the called device.

Next, the terminating mobile IMS network 30 returns a code 403 Forbidden response to the originating fixed IMS network 20 indicating that access to the media resource requested by the originating party in the SIP session (i.e., the terminating party's equipment) is prohibited (F8), and in response, the originating fixed IMS network 20 returns a code 403 Forbidden response to the originating party's equipment (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11).

Then, the session related to the INVITE request from the calling device ends.

(In the real world / Pattern 6)
FIG. 7 is a diagram illustrating a basic sequence pattern 6 of an operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 7 is a diagram explaining the basic sequence when the anonymous call rejection function is set for the receiving device (i.e., mobile phone) (and the anonymous call rejection service is not set), and the calling device sets the caller number to anonymous (specifically, adds the number "184" before the called party's telephone number) and makes a call. Note that the basic sequence patterns 5 to 8 shown in Figures 6 to 9 may differ depending on the contracted carrier of the IMS terminal 50, for example, and as a result, the contents of each pattern are different.

The operations F1 to F6 in basic sequence pattern 6 shown in Figure 7 are the same as the operations F1 to F6 in basic sequence pattern 1 shown in Figure 2.

In the basic sequence pattern 6 shown in FIG. 7, a code 183 Session Progress response is returned from the originating fixed IMS network 20 to the originating device (F6), and then a code 183 Session Progress response indicating the progress of the call in the SIP session is returned from the terminating mobile IMS network 30 to the originating fixed IMS network 20 (F7). In response to this, a code 183 Session Progress response is returned from the originating fixed IMS network 20 to the originating device (F8).

Furthermore, silent data is sent as RTP (Real time Transport Protocol) from the receiving mobile IMS network 30 to the calling device via the originating fixed IMS network 20 (F9). At this time, the calling device does not ring (because the call has been rejected), and the call history remains on the receiving device.

Then, the terminating mobile IMS network 30 returns a code 183 Session Progress response indicating the progress of the call in the SIP session to the originating fixed IMS network 20 (F10), and in response, the originating fixed IMS network 20 returns a code 183 Session Progress response to the calling device (F11).

Next, the terminating mobile IMS network 30 returns a code 603 Decline response to the originating fixed IMS network 20 indicating that the terminating device has rejected the SIP session (F12), and in response, the originating fixed IMS network 20 returns a code 603 Decline response to the originating device (F13).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F14), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F15).

Then, the session related to the INVITE request from the calling device ends.

(In the real world / Pattern 7)
FIG. 8 is a diagram illustrating a basic sequence pattern 7 of an operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 8 is a diagram explaining the basic sequence when the anonymous call rejection function is set for the receiving device (i.e., mobile phone) (and the anonymous call rejection service is not set), and the calling device sets the caller number to anonymous (specifically, adds the number "184" before the called party's telephone number) and makes a call. Note that the basic sequence patterns 5 to 8 shown in Figures 6 to 9 may differ depending on the contracted carrier of the IMS terminal 50, for example, and as a result, the contents of each pattern are different.

The operations F1 to F4 in basic sequence pattern 7 shown in Figure 8 are similar to the operations F1 to F4 in basic sequence pattern 1 shown in Figure 2.

In the basic sequence pattern 7 shown in FIG. 8, after a code 100 Trying response is sent from the originating fixed IMS network 20 to the originating device (F4), a code 486 Busy Here response is sent from the terminating mobile IMS network 30 to the originating fixed IMS network 20, indicating that the media resource requested by the originating device in the SIP session is currently busy and the session cannot be started (F5), and in response to this, a code 486 Busy Here response is sent from the originating fixed IMS network 20 to the originating device (F6). At this time, the terminating device does not ring (because the incoming call has been rejected).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F7), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F8).

Then, the session related to the INVITE request from the calling device ends.

(In the real world / Pattern 8)
FIG. 9 is a diagram illustrating a basic sequence pattern 8 of the operation according to the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a mobile phone is actually present as the called device and is not busy, and the calling device disconnects communication.

Figure 9 is a diagram explaining the basic sequence when the anonymous call rejection function is set for the receiving device (i.e., mobile phone) (however, the anonymous call rejection service is not set), and the calling device sets the caller number to anonymous (specifically, adds the number "184" before the called party's telephone number) and makes a call. Note that the basic sequence patterns 5 to 8 shown in Figures 6 to 9 may differ depending on the contracted carrier of the IMS terminal 50, for example, and as a result, the contents differ from one another.

The operations F1 to F6 in basic sequence pattern 8 shown in Figure 9 are the same as the operations F1 to F6 in basic sequence pattern 1 shown in Figure 2.

In the basic sequence pattern 8 shown in FIG. 9, the terminating mobile IMS network 30 returns a code 183 Session Progress response to the calling device via the originating fixed IMS network 20 (F5, F6), and sends silent data or a busy tone indicating that the called device is busy as RTP (Real time Transport Protocol) (F7). At this time, the called device does not ring (because the call has been rejected).

Next, the terminating mobile IMS network 30 returns a code 180 Ringing response to the originating fixed IMS network 20 indicating that a ringtone is ringing in the SIP session (F8), and in response, the originating fixed IMS network 20 returns a code 180 Ringing response to the calling device (F9).

Then, the terminating mobile IMS network 30 returns a code 486 Busy Here response to the originating fixed IMS network 20, indicating that the media resource requested by the originating side in the SIP session is currently busy and the session cannot be started (F10), and in response, the originating fixed IMS network 20 returns a code 486 Busy Here response to the originating device (F11).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F12), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F13).

Then, the session related to the INVITE request from the calling device ends.

Note that the operations of F10 to F13 in pattern 8 of the basic sequence shown in Figure 9 may differ from the contents (operations) shown in Figure 9, but this does not affect the configuration of the present invention (specifically, the operational sequence related to determining the usage status of a telephone number).

(If the line is busy / No. 1)
10 is a diagram for explaining a basic sequence pattern 1 of an operation by the INVITE method in IMS interconnection when a mobile phone is actually present and busy as a called device between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30. This basic sequence is defined in the TTC standard TR-1088.

The calling device sends an INVITE request to the called device via the calling fixed IMS network 20 and the called mobile IMS network 30, such as the mobile phone network of the called device's contract carrier (F1). In response, an INVITE request is sent from the calling fixed IMS network 20 to the called mobile IMS network 30 (F2).

In response to this, the terminating mobile IMS network 30 returns a code 100 Trying response to the originating fixed IMS network 20 indicating that the request has been accepted in the SIP session (F3), and in response to this, the originating fixed IMS network 20 returns a code 100 Trying response to the calling device (F4).

Then, the terminating mobile IMS network 30 returns a code 486 Busy Here response to the originating fixed IMS network 20, indicating that the media resource requested by the originating side in the SIP session is currently busy and the session cannot be started (F5), and in response, the originating fixed IMS network 20 returns a 486 Busy Here response to the originating device (F6).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F7), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F8). This ends the session related to the INVITE request from the calling device.

(If the line is busy / No. 2)
Fig. 11 is a diagram for explaining a pattern 2 of a basic sequence of an operation when a mobile phone is actually present and busy as a receiving device by the INVITE method in the IMS interconnection between a calling device, a calling fixed IMS network 20, and a receiving mobile IMS network 30. Note that the basic sequence pattern 1 shown in Fig. 10 and the basic sequence pattern 2 shown in Fig. 11 may differ depending on the contract carrier of the IMS terminal 50, for example, and the contents are different due to this.

The calling device sends an INVITE request to the called device via the calling fixed IMS network 20 and the called mobile IMS network 30, such as the mobile phone network of the called device's contract carrier (F1). In response, an INVITE request is sent from the calling fixed IMS network 20 to the called mobile IMS network 30 (F2).

In response to this, the terminating mobile IMS network 30 returns a code 100 Trying response to the originating fixed IMS network 20 indicating that the request has been accepted in the SIP session (F3), and in response, the originating fixed IMS network 20 returns a code 100 Trying response to the calling device (F4).

Then, the terminating mobile IMS network 30 returns a code 183 Session Progress response indicating the progress of the call in the SIP session to the originating fixed IMS network 20 (F5), and in response, the originating fixed IMS network 20 returns a code 183 Session Progress response to the calling device (F6).

Furthermore, a busy tone indicating that the receiving device is busy is sent from the receiving mobile IMS network 30 to the calling device via the originating fixed IMS network 20 as RTP (Real time Transport Protocol) (F7).

Then, the terminating mobile IMS network 30 returns a code 487 Request Terminated response indicating the termination of the request in the SIP session (in other words, the end of the session) to the originating fixed IMS network 20 (F8), and in response, the originating fixed IMS network 20 returns a code 487 Request Terminated response to the calling device (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11). This ends the session related to the INVITE request from the calling device.

(In case of missing number)
12 is a diagram for explaining a basic sequence of operations in the INVITE method in IMS interconnection when the called device (in other words, the telephone number) is a missing number between the calling device, the calling fixed IMS network 20, and the called mobile IMS network 30. This basic sequence is defined in the TTC standard TR-1088.

The calling device sends an INVITE request to the called device via the calling fixed IMS network 20 and the called mobile IMS network 30, such as the mobile phone network of the called device's contract carrier (F1). In response, an INVITE request is sent from the calling fixed IMS network 20 to the called mobile IMS network 30 (F2).

In response to this, the terminating mobile IMS network 30 returns a code 100 Trying response to the originating fixed IMS network 20 indicating that the request has been accepted in the SIP session (F3), and in response to this, the originating fixed IMS network 20 returns a code 100 Trying response to the calling device (F4).

Then, the terminating mobile IMS network 30 returns a code 404 Not Found response to the originating fixed IMS network 20 indicating that the media resource requested by the originating side in the SIP session cannot be found (F5), and in response, the originating fixed IMS network 20 returns a 404 Not Found response to the originating device (F6).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F7), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F8). This ends the session related to the INVITE request from the calling device.

(Telephone number investigation device)
FIG. 13 is a block diagram showing a configuration of a telephone number research device 10 according to an embodiment.

The telephone number investigation device 10 according to the embodiment is connected to a plurality of IMS terminals 50 connected to a terminating mobile IMS network 30 via an originating fixed IMS network 20, and sends an INVITE request to the originating fixed IMS network 20 (toward the IMS terminal 50 being investigated) by adding SDP parameters to the INVITE request for the IMS terminal 50 being investigated, and receives a response message via the originating fixed IMS network 20, and determines the usage status of the telephone number of the IMS terminal 50 being investigated according to the response message.

The telephone number investigation device 10 includes a network interface unit 11, a message exchange control unit 12, a telephone number investigation determination unit 13, a telephone number history generation unit 14, and a telephone number history database (DB) 15.

The network interface unit 11 functions as a communication interface that enables the telephone number investigation device 10 to communicate in accordance with the SIP protocol.

The message exchange control unit 12 sends an INVITE request including SDP parameters for determination to the IMS terminal 50 being investigated, and also receives a message (e.g., a response with a specified code in a SIP session) from the destination mobile IMS network 30 (including SIP servers 30a, 30b, and 30c).

The telephone number investigation and determination unit 13 determines whether the IMS terminal 50 being investigated on the receiving side actually exists or not, depending on the message (e.g., a response with a specific code in a SIP session) received via the message exchange control unit 12, and further determines the validity of the telephone number of the IMS terminal 50 being investigated (in other words, the usage status of the telephone number).

The telephone number history generation unit 14 creates a telephone number history database 15 by adding a timestamp indicating the date and time of the judgment to each judgment result from the telephone number investigation judgment unit 13 and recording them in chronological order on a recording medium.

Although the data structure of the telephone number history database 15 (in other words, the recorded data items) is not limited to a specific structure or items, the telephone number history information stored in the telephone number history database 15 may include, for example, a combination of the "telephone number" to be investigated for each investigation (in other words, each time an INVITE request is sent), the "error code" returned from the terminating mobile IMS network 30, the "investigation date" (i.e., a timestamp), the "existent/missing number determination result," and "other layer information" regarding the layer returned from the terminating mobile IMS network 30.

The telephone number history information stored in the telephone number history database 15 may also include, in addition to the data items mentioned above, for example, the type of IMS terminal 50 being investigated (specifically, mobile phone, data communication-only terminal), the "new subscriber number" which is the transfer destination or contact telephone number identified during the investigation, the "corporate name/individual name" which owns the telephone number, "attribute information" such as address and age, "map link information," and "credit information" for evaluating credit.

For example, when the telephone number investigation device 10 investigates the usage of the telephone number "090-XXXX-XXXX", the investigation information is recorded sequentially in the telephone number history database 15 for each determination made by the telephone number investigation determination unit 13, and is accumulated and stored as history information.

The telephone number history database 15 may be implemented on a large-capacity recording medium, such as a semiconductor memory, a hard disk, or an optical memory such as a DVD (Digital Versatile Disc).

The telephone number investigation device 10 is configured to include a microprocessor having built-in memory (not shown) in which a predetermined program (including the telephone number investigation program according to the embodiment) is recorded, or a microprocessor to which an external memory (not shown) in which a predetermined program is recorded is attached, and an LSI (Large Scale Integration) that performs peripheral control including communication control.

The microprocessor sequentially reads and executes the predetermined programs (including the telephone number investigation program according to the embodiment) recorded in the memory (not shown), thereby configuring the network interface unit 11, the message exchange control unit 12, the telephone number investigation determination unit 13, and the telephone number history generation unit 14, and realizing the predetermined functions of the telephone number investigation device 10.

(Method of investigating telephone numbers)
As an example of a specific configuration of the telephone number investigation method according to the present invention, the telephone number investigation method according to the embodiment is a method of investigating the usage status of the telephone number of the IMS terminal 50 to be investigated by using a computer (specifically, a telephone number investigation device 10) connected to a plurality of IMS terminals 50 connected to the terminating mobile IMS network 30 via the originating fixed IMS network 20, and includes a step of adding an SDP parameter to an INVITE request for the IMS terminal 50 to be investigated and transmitting the INVITE request to the originating fixed IMS network 20 (to the IMS terminal 50 to be investigated), a step of receiving a response message via the originating fixed IMS network 20, and a step of determining the usage status of the telephone number of the IMS terminal 50 to be investigated according to the response message, and the SDP parameters are described as follows: the network protocol is IPv4, the media type is audio only, the media transport protocol is RTP/AVP only, and the voice codec includes G.711 μ-law and G.722.

Here, in the telephone number investigation method according to the present invention, the calling device (specifically, telephone number investigation device 10) sets the telephone number to be withheld (specifically, adds "184" to the called telephone number) and transmits the telephone number of the IMS terminal 50 to be investigated. This makes it possible to prevent the ringer of the IMS terminal 50 to be investigated from ringing when investigating the usage status of the telephone number of the IMS terminal if at least one of the withheld call rejection service and withheld call rejection function is set.

The telephone number investigation method described below can be implemented, for example, by executing a telephone number investigation program in a computer (specifically, telephone number investigation device 10) and executing each of the relevant steps in accordance with the program.

As SDP parameters, among the determination SDP parameters, IPv4 is described (in other words, used) for the network protocol (in other words, Internet Protocol, IP version) and offered, and other determination SDP parameters are described as follows. The following description of the determination SDP parameters is referred to as "SDP for IPv4".
○ Media type: audio only ○ Media transport protocol: RTP/AVP only ○ Audio codec: includes G.711 μ-law and G.722

(Reality determination/part 1)
FIG. 14 is a diagram illustrating the first operation sequence when an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and when a mobile phone actually exists as the IMS terminal 50 to be investigated but is not busy.

Figure 14 is a diagram that explains the operation sequence when there is no setting to reject incoming calls when the caller has set the phone number to be withheld. In other words, Figure 14 is a diagram that explains the operation sequence when the anonymous call rejection service is not set and the anonymous call rejection function is not set.

The message exchange control unit 12 of the telephone number investigation device 10 sends an INVITE request to the IMS terminal 50 to be investigated via the originating fixed IMS network 20 and the terminating mobile IMS network 30, such as the mobile telephone network of the contracted carrier of the IMS terminal 50 to be investigated (F1, F2). At this time, the above-mentioned SDP for IPv4 is described as the SDP parameter for determination (note that the network protocol is IPv4) included in the INVITE request.

In response to this, a code 100 Trying response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request has been accepted in the SIP session (F3, F4).

Then, a code 183 Session Progress response indicating the progress of the call in the SIP session is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F5, F6).

At this time, the call bell of the IMS terminal 50 being investigated on the receiving side rings, and an RBT (Ringing Back Tone) is sent as an RTP (Real time Transport Protocol) from the receiving mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the calling fixed IMS network 20 (F7).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a mobile phone actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 sends a CANCEL request, which is an instruction to terminate the SIP session, to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F8, F9).

When the message exchange control unit 12 of the telephone number investigation device 10 receives the code 183 Session Progress response, it immediately (or more precisely, almost simultaneously with receiving the code 183 Session Progress response) sends a CANCEL request to stop the ringing of the call bell of the IMS terminal 50 being investigated on the called side. This causes the ringing of the call bell of the IMS terminal 50 being investigated on the called side to stop in an extremely short time.

Here, in the basic sequence of operation, for example, pattern 1 and pattern 2 (i.e., the basic sequence when the anonymous call rejection service is not set and the anonymous call rejection function is not set; see Figures 2 and 3) between the calling device, the calling device, and the calling fixed IMS network 20 and the called mobile IMS network 30 by the INVITE method in IMS interconnection when a mobile phone is actually present as the called device and is not busy, the normal sequence is the operation in which a code 183 Session Progress response (F5, F6) is returned in response to an INVITE request (F1, F2) from the calling device. However, depending on the contract carrier of the IMS terminal 50, there may be irregular cases where a code 180 Ringing response is returned without a code 183 Session Progress response being returned. Therefore, even if the telephone number investigation determination unit 13 of the telephone number investigation device 10 receives a code 180 Ringing response without receiving a code 183 Session Progress response (F5, F6), it determines that a mobile phone actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).Then, the message exchange control unit 12 of the telephone number investigation device 10 transmits a CANCEL request, which is an instruction to end the session in the SIP session, to the receiving mobile IMS network 30 via the calling fixed IMS network 20.

That is, when the telephone number investigation determination unit 13 of the telephone number investigation device 10 receives a code 183 Session Progress response or a code 180 Ringing response in response to the INVITE request, it determines that a mobile phone exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated exists). Then, the message exchange control unit 12 of the telephone number investigation device 10 sends a CANCEL request. In other words, when the message exchange control unit 12 of the telephone number investigation device 10 receives a code 18X response, it sends a CANCEL request, and if the anonymous call rejection service and anonymous call rejection function are not set for the IMS terminal 50 to be investigated on the receiving side (specifically, the mobile phone), it promptly stops the ringing of the ringer of the receiving side device (i.e., the mobile phone as the IMS terminal 50 to be investigated).

In response to a CANCEL request from the calling device (specifically, the telephone number investigation device 10), a code 200 OK response is returned from the called mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the calling fixed IMS network 20 in the SIP session, indicating that the request (specifically, the CANCEL request) has been successfully processed (F10, F11), and a code 487 Request Terminated response is returned in the SIP session, indicating that the request has been cancelled (in other words, the session has ended) (F12, F13).

In response to this, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F14, F15). This ends the session between the telephone number investigation device 10 and the destination IMS terminal 50 being investigated.

(Reality determination/part 2)
FIG. 15 is a diagram illustrating a second operational sequence for a case in which an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and a mobile phone actually exists as the IMS terminal 50 to be investigated but is not busy.

Figure 15 is a diagram that explains the operation sequence when at least one of the anonymous call rejection service and anonymous call rejection function is set.

The operations F1 to F6 in the operation sequence 2 shown in FIG. 15 are the same as the operations F1 to F6 in the operation sequence 1 shown in FIG. 14. Note that the above SDP for IPv4 is described for the SDP parameters for determination (note that the network protocol is IPv4) included in the INVITE request.

In the second operation sequence shown in FIG. 15, a code 183 Session Progress response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F5, F6), and an incoming call rejection guidance or RBT (Ringing Back Tone) is sent as RTP (Real time Transport Protocol) (F7) to inform the caller that the incoming call has been rejected because the caller has set the telephone number to be withheld. At this time, the call bell of the IMS terminal 50 to be investigated on the terminating side does not ring (because the incoming call has been rejected).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a mobile phone actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

The operations from F8 to F15 in the operation sequence 2 shown in FIG. 15 are the same as the operations from F8 to F15 in the operation sequence 1 shown in FIG. 14. However, since the call bell of the IMS terminal 50 being investigated on the called side is not ringing to begin with, the call bell of the IMS terminal 50 being investigated on the called side does not stop ringing when the CANCEL request is sent. Then, the session between the telephone number investigation device 10 and the IMS terminal 50 being investigated on the called side is terminated.

(Reality determination/part 3)
FIG. 16 is a diagram illustrating the third operation sequence when an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and when a mobile phone actually exists as the IMS terminal 50 to be investigated but is not busy.

Figure 16 is a diagram that explains the operation sequence when the anonymous call rejection function is set (however, the anonymous call rejection service is not set).

The message exchange control unit 12 of the telephone number investigation device 10 sends an INVITE request to the IMS terminal 50 to be investigated via the originating fixed IMS network 20 and the terminating mobile IMS network 30, such as the mobile telephone network of the contracted carrier of the IMS terminal 50 to be investigated (F1, F2). At this time, the above-mentioned SDP for IPv4 is described as the SDP parameter for determination (note that the network protocol is IPv4) included in the INVITE request.

In response to this, a code 100 Trying response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request has been accepted in the SIP session (F3, F4).

Then, a code 486 Busy Here response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the media resource requested by the originating side in the SIP session is currently busy and the session cannot be started (F5, F6). At this time, the call bell does not ring on the terminating side IMS terminal 50 being investigated (because the incoming call has been rejected).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a mobile phone actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment response in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F7, F8). This ends the session between the telephone number investigation device 10 and the destination IMS terminal 50 being investigated.

(Determining presence when a line is busy/Part 1)
FIG. 17 is a diagram illustrating the first operational sequence in the case where an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and a mobile phone actually exists as the IMS terminal 50 to be investigated and is in use.

Note that Figure 17 is a diagram explaining the operation sequence when the anonymous call rejection service is not set and the anonymous call rejection function is not set.

The message exchange control unit 12 of the telephone number investigation device 10 sends an INVITE request to the IMS terminal 50 to be investigated via the originating fixed IMS network 20 and the terminating mobile IMS network 30, such as the mobile telephone network of the contracted carrier of the IMS terminal 50 to be investigated (F1, F2). At this time, the above-mentioned SDP for IPv4 is described as the SDP parameter for determination (note that the network protocol is IPv4) included in the INVITE request.

In response to this, a code 100 Trying response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request has been accepted in the SIP session (F3, F4).

Then, a code 486 Busy Here response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the media resource requested by the originating side in the SIP session is currently busy and the session cannot be started (F5, F6).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a mobile phone actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment response in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F7, F8). This ends the session between the telephone number investigation device 10 and the destination IMS terminal 50 being investigated.

(Determining presence when the line is busy/Part 2)
FIG. 18 is a diagram illustrating a second operational sequence in which an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and a mobile phone actually exists as the IMS terminal 50 to be investigated and is in use.

FIG. 18 is a diagram for explaining the operation sequence when the anonymous call rejection service and anonymous call rejection function are not set. Note that the operation sequence 1 shown in FIG. 17 and the operation sequence 2 shown in FIG. 18 may differ depending on the contracted carrier of the IMS terminal 50, for example, and the contents are different due to this.

The message exchange control unit 12 of the telephone number investigation device 10 sends an INVITE request to the IMS terminal 50 to be investigated via the originating fixed IMS network 20 and the terminating mobile IMS network 30, such as the mobile telephone network of the contracted carrier of the IMS terminal 50 to be investigated (F1, F2). At this time, the above-mentioned SDP for IPv4 is described as the SDP parameter for determination (note that the network protocol is IPv4) included in the INVITE request.

In response to this, a code 100 Trying response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request has been accepted in the SIP session (F3, F4).

Then, a code 183 Session Progress response indicating the progress of the call in the SIP session is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F5, F6), and a busy tone indicating that the terminating device (i.e., the IMS terminal 50 being investigated) is busy is sent as RTP (Real time Transport Protocol) (F7).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a mobile phone actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 sends a CANCEL request, which is an instruction to terminate the SIP session, to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F8, F9).

In other words, when the message exchange control unit 12 of the telephone number investigation device 10 receives the code 183 Session Progress response, it immediately sends a CANCEL request (or, more precisely, almost simultaneously with receiving the code 183 Session Progress response).

In response to a CANCEL request from the calling device (specifically, the telephone number investigation device 10), a code 200 OK response is returned from the called mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the calling fixed IMS network 20 in the SIP session, indicating that the request (specifically, the CANCEL request) has been successfully processed (F10, F11), and a code 487 Request Terminated response is returned in the SIP session, indicating that the request has been cancelled (in other words, the session has ended) (F12, F13).

In response to this, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F14, F15). This ends the session between the telephone number investigation device 10 and the destination IMS terminal 50 being investigated.

(Missing number determination)
FIG. 19 is a diagram illustrating the operation sequence in the case where an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and the IMS terminal 50 to be investigated (in other words, the telephone number) is a missing number.

The message exchange control unit 12 of the telephone number investigation device 10 sends an INVITE request to the IMS terminal 50 to be investigated via the originating fixed IMS network 20 and the terminating mobile IMS network 30, such as the mobile phone network of the contracted carrier of the IMS terminal 50 to be investigated (F1, F2). At this time, the above-mentioned SDP for IPv4 is described as the SDP parameter for determination (note that the network protocol is IPv4) included in the INVITE request.

In response to this, a code 100 Trying response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request has been accepted in the SIP session (F3, F4).

Then, the terminating mobile IMS network 30 returns a code 404 Not Found response to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the media resource requested by the originating side in the SIP session cannot be found (F5, F6).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that the IMS terminal 50 to be investigated on the called party is a missing number (i.e., the telephone number of the IMS terminal 50 to be investigated is a missing number). Note that a missing number also includes the case where the IMS terminal 50 to be investigated on the called party has been cancelled.

Then, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F7, F8). This ends the session related to the INVITE request from the telephone number investigation device 10.

(Misjudgment of existence)
Here, Fig. 20 is a diagram for explaining an operation sequence in the case where the IMS terminal 50 (in other words, the telephone number) to be investigated is a missing number when an offer is made by describing IPv4 as the network protocol as the SDP parameter and describing only G.711 μ-law as the voice codec of the SDP for IPv4 as the SDP parameter for judgment (in other words, without including G.722). The basic sequence on which this operation sequence is based is specified in TR-1088 of the TTC standard.

In this case, in response to an INVITE request (F1, F2) from the telephone number investigation device 10 (specifically, the message exchange control unit 12), a code 100 Trying response indicating that the request has been accepted in the SIP session is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F3, F4), and a code 183 Session Progress response indicating the progress of the call in the SIP session is returned (F5, F6).

This response is the same as the operation sequence (part 1, part 2) when a mobile phone actually exists as the IMS terminal 50 being investigated on the receiving side (see Figures 14 and 15).

As a result, even though the IMS terminal 50 being investigated (in other words, the telephone number) is actually a missing number, the telephone number investigation determination unit 13 of the telephone number investigation device 10 erroneously determines that a mobile phone actually exists as the IMS terminal 50 being investigated on the receiving side (and the message exchange control unit 12 sends a CANCEL request).

For this reason, when offering an SDP parameter that describes IPv4 as the network protocol among the SDP parameters for determination, the other SDP parameters for determination should describe the voice codec to include G.722 in addition to G.711 μ-law (i.e., offer G.711 μ-law and G.722 simultaneously).

As a result, as shown in FIG. 19, in response to an INVITE request (F1, F2) from the telephone number investigation device 10 (specifically, the message exchange control unit 12), a code 100 Trying response indicating that the request has been accepted in the SIP session is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F3, F4), and a code 404 Not Found response indicating that the media resource requested by the originating side cannot be found in the SIP session is returned (F5, F6), making it possible to correctly determine that the IMS terminal 50 (in other words, the telephone number) being investigated on the terminating side is a missing number.

(Data communication only terminal)
21 to 25 are diagrams for explaining a basic sequence of operations between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30 when an IMS terminal 50 as a called device is a data communication-only terminal by the INVITE method in IMS interconnection. Note that the basic sequence of operations between a calling device according to the embodiment (specifically, a telephone number research device 10) and an IMS terminal 50 which is a data communication-only terminal is not limited to the contents shown in Figs. 21 to 25, and may be in accordance with, for example, the contents specified in TTC standard JJ-90.30, TTC standard JJ-90.26, TTC standard JF-IETF-RFC3398, TTC standard TR-1088, TTC standard JT-Q850, and TTC specification TS-1025.

Communication is carried out between the calling device and the called device (specifically, a data communication-only terminal) connected to the called mobile IMS network 30 via the calling fixed IMS network 20, the calling IBCF 21, the called IBCF 31, and the called mobile IMS network 30.

(Basic sequence/pattern 1)
FIG. 21 is a diagram explaining a basic sequence pattern 1 of an operation by the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, in the case where a data communication-only terminal actually exists as the called device.

The calling device sends an INVITE request to the called device via the calling fixed IMS network 20 and the called mobile IMS network 30, such as the mobile phone network of the contracted carrier of the called device (F1). In response, the calling fixed IMS network 20 sends an INVITE request to the called mobile IMS network 30 (F2).

In response to this, the terminating mobile IMS network 30 returns a code 100 Trying response to the originating fixed IMS network 20 indicating that the request has been accepted in the SIP session (F3), and in response to this, the originating fixed IMS network 20 returns a code 100 Trying response to the calling device (F4).

Then, the terminating mobile IMS network 30 returns a code 183 Session Progress response indicating the progress of the call in the SIP session to the originating fixed IMS network 20 (F5), and in response, the originating fixed IMS network 20 returns a code 183 Session Progress response to the calling device (F6).

Furthermore, guidance is sent from the terminating mobile IMS network 30 to the originating device via the originating fixed IMS network 20 to the originating device, indicating that the terminating device is for data communication only (F7).

Then, the terminating mobile IMS network 30 returns a code 480 Temporarily Unavailable response to the originating fixed IMS network 20, indicating that the media resource requested by the originating party in the SIP session (i.e., the terminating party's equipment) is temporarily unavailable (F8), and in response, the originating fixed IMS network 20 returns a code 480 Temporarily Unavailable response to the originating party's equipment (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11). This ends the session related to the INVITE request from the calling device.

(Basic sequence/pattern 2)
FIG. 22 is a diagram explaining a basic sequence pattern 2 of the operation by the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a data communication-only terminal actually exists as the called device.

Note that the basic sequence patterns 1 to 5 shown in Figures 21 to 25 may differ depending on, for example, the contract carrier or contract type of the IMS terminal 50, and as a result, the contents of each pattern may differ from one another.

The operations F1 to F6 in pattern 2 of the basic sequence shown in FIG. 22 are the same as the operations F1 to F6 in pattern 1 of the basic sequence shown in FIG. 21.

In the basic sequence pattern 2 shown in FIG. 22, following the operation of F6, guidance is sent from the terminating mobile IMS network 30 to the calling device via the originating fixed IMS network 20 to the effect that the terminating device cannot be reached (in other words, cannot be connected) (F7).

Then, the terminating mobile IMS network 30 returns a code 403 Forbidden response to the originating fixed IMS network 20, indicating that access to the media resource requested by the originating party in the SIP session (i.e., the terminating party's equipment) is prohibited (F8), and in response, the originating fixed IMS network 20 returns a code 403 Forbidden response to the originating party's equipment (F9).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F10), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F11). This ends the session related to the INVITE request from the calling device.

(Basic sequence/pattern 3)
FIG. 23 is a diagram explaining a basic sequence pattern 3 of an operation by the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a data communication-only terminal actually exists as a called device.

The operations F1 to F4 in pattern 3 of the basic sequence shown in FIG. 23 are similar to the operations F1 to F4 in pattern 1 of the basic sequence shown in FIG. 21.

In the basic sequence pattern 3 shown in FIG. 23, following the operation of F4, a code 487 Request Terminated response indicating the termination of the request in the SIP session (in other words, the end of the session) is returned from the terminating mobile IMS network 30 to the originating fixed IMS network 20 (F5), and in response to this, a code 487 Request Terminated response is returned from the originating fixed IMS network 20 to the calling device (F6).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F7), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F8). This ends the session related to the INVITE request from the calling device.

(Basic sequence/pattern 4)
FIG. 24 is a diagram explaining a basic sequence pattern 4 of an operation by the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a data communication-only terminal actually exists as a called device.

The operations F1 to F4 in pattern 4 of the basic sequence shown in FIG. 24 are the same as the operations F1 to F4 in pattern 1 of the basic sequence shown in FIG. 21.

In the basic sequence pattern 4 shown in FIG. 24, following the operation of F4, the terminating mobile IMS network 30 returns a Server Internal Error response code 500 to the originating fixed IMS network 20, indicating that an error has occurred inside the server in the SIP session (F5), and in response, the originating fixed IMS network 20 returns a 500 Server Internal Error response to the calling device (F6).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the called mobile IMS network 30 (F7), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F8). This ends the session related to the INVITE request from the calling device.

(Basic sequence/pattern 5)
FIG. 25 is a diagram for explaining a basic sequence pattern 5 of an operation by the INVITE method in IMS interconnection between a calling device, a calling fixed IMS network 20, and a called mobile IMS network 30, when a data communication-only terminal actually exists as a called device.

The operations F1 to F4 in pattern 5 of the basic sequence shown in FIG. 25 are the same as the operations F1 to F4 in pattern 1 of the basic sequence shown in FIG. 21.

In the basic sequence pattern 5 shown in FIG. 25, following the operation of F4, a code 488 Not Acceptable Here response is returned from the terminating mobile IMS network 30 to the originating fixed IMS network 20, indicating that acceptance has been rejected by the terminating device in the SIP session (F5), and in response, a code 488 Not Acceptable Here response is returned from the originating fixed IMS network 20 to the originating device (F6).

In response to this, an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session is returned from the calling device to the calling fixed IMS network 20 (F7), and in response to this, an ACK response is returned from the calling fixed IMS network 20 to the called mobile IMS network 30 (F8). This ends the session related to the INVITE request from the calling device.

(Reality determination/part 1)
FIG. 26 is a diagram illustrating part 1 of an operation sequence in which an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and a data communication-only terminal actually exists as the IMS terminal 50 to be investigated.

The operation sequence shown in FIG. 26 is an operation sequence when the basic sequence of operation between the calling device, the calling fixed IMS network 20, and the called mobile IMS network 30, when a data communication-only terminal actually exists as the called device, follows pattern 1 of the basic sequence shown in FIG. 21.

The message exchange control unit 12 of the telephone number investigation device 10 sends an INVITE request to the IMS terminal 50 to be investigated via the originating fixed IMS network 20 and the terminating mobile IMS network 30, such as the mobile phone network of the contracted carrier of the IMS terminal 50 to be investigated (F1, F2). At this time, the above-mentioned SDP for IPv4 is described as the SDP parameter for determination (note that the network protocol is IPv4) included in the INVITE request.

In response to this, a code 100 Trying response is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request has been accepted in the SIP session (F3, F4).

Then, a code 183 Session Progress response indicating the progress of the call in the SIP session is returned from the terminating mobile IMS network 30 to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F5, F6).

Furthermore, guidance is sent from the terminating mobile IMS network 30 to the originating device via the originating fixed IMS network 20 to the originating device, indicating that the terminating device (i.e., the IMS terminal 50 being investigated) is for data communication only (F7).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a data communication-only terminal actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 sends a CANCEL request, which is an instruction to terminate the SIP session, to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F8, F9).

In response to this, the terminating mobile IMS network 30 returns a code 200 OK response to the telephone number investigation device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that the request (specifically, the CANCEL request) has been processed successfully in the SIP session (F10, F11), and also returns a code 487 Request Terminated response indicating that the request has been cancelled in the SIP session (in other words, the end of the session) (F12, F13).

In response to this, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F14, 15). This ends the session related to the INVITE request from the telephone number investigation device 10.

(Reality determination/part 2)
FIG. 27 is a diagram illustrating a second operational sequence in which an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the judgment SDP parameters, and a data communication-only terminal actually exists as the IMS terminal 50 to be investigated.

The operation sequence shown in FIG. 27 is an operation sequence in which the basic sequence of operations between the calling device, the calling fixed IMS network 20, and the called mobile IMS network 30, when a data communication-only terminal actually exists as the called device, follows pattern 2 of the basic sequence shown in FIG. 22.

The operations F1 to F6 in the operation sequence 2 shown in FIG. 27 are the same as the operations F1 to F6 in the operation sequence 1 shown in FIG. 26. Note that the above SDP for IPv4 is described for the SDP parameters for determination (note that the network protocol is IPv4) included in the INVITE request.

In the second operation sequence shown in FIG. 27, following the operation of F6, guidance is sent from the terminating mobile IMS network 30 to the telephone number research device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 to the effect that the terminating device cannot be reached (in other words, cannot be connected) (F7).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a data communication-only terminal actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

The operations F8 to F15 in the operation sequence part 2 shown in FIG. 27 are the same as the operations F8 to F15 in the operation sequence part 1 shown in FIG. 26.

Then, the session related to the INVITE request from the telephone number investigation device 10 ends.

(Reality determination/part 3)
FIG. 28 is a diagram explaining the third basic sequence in the case where an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the SDP parameters for determination, and a data communication-only terminal actually exists as the IMS terminal 50 to be investigated.

The operation sequence shown in FIG. 28 is an operation sequence in which the basic sequence of operations between the calling device, the calling fixed IMS network 20, and the called mobile IMS network 30, when a data communication-only terminal actually exists as the called device, follows pattern 3 of the basic sequence shown in FIG. 23.

The operations F1 to F4 in the operation sequence 3 shown in FIG. 28 are the same as the operations F1 to F4 in the operation sequence 1 shown in FIG. 26. Note that the above SDP for IPv4 is described for the SDP parameters for determination (note that the network protocol is IPv4) included in the INVITE request.

In the third operation sequence shown in FIG. 28, following the operation of F4, a code 487 Request Terminated response indicating the termination of the request (in other words, the end of the session) in the SIP session is returned from the terminating mobile IMS network 30 to the telephone number research device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20 (F5, F6).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a data communication-only terminal actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment response in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F7, F8). This ends the session related to the INVITE request from the telephone number investigation device 10.

(Reality determination/part 4)
FIG. 29 is a diagram explaining the fourth basic sequence in the case where an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the SDP parameter for determination, and a data communication-only terminal actually exists as the IMS terminal 50 to be investigated.

The operation sequence shown in FIG. 29 is an operation sequence when the basic sequence of operations between the calling device, the calling fixed IMS network 20, and the called mobile IMS network 30, when a data communication-only terminal actually exists as the called device, follows pattern 4 of the basic sequence shown in FIG. 24.

The operations F1 to F4 in the operation sequence No. 4 shown in FIG. 29 are the same as the operations F1 to F4 in the operation sequence No. 1 shown in FIG. 26. Note that as the SDP parameters included in the INVITE request, the above SDP for IPv4 is described for the determination SDP parameters (note that the network protocol is IPv4).

In the fourth operation sequence shown in FIG. 29, following the operation of F4, a code 500 Server Internal Error response is returned from the terminating mobile IMS network 30 to the telephone number research device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that an error has occurred inside the server during the SIP session (F5, F6).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a data communication-only terminal actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment response in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F7, F8). This ends the session related to the INVITE request from the telephone number investigation device 10.

(Reality test/part 5)
Figure 30 is a diagram explaining the fifth basic sequence when an offer is made by describing IPv4 as the network protocol as the SDP parameters and describing the above-mentioned SDP for IPv4 as the SDP parameters for determination, and when a data communication-only terminal actually exists as the IMS terminal 50 to be investigated.

The operation sequence shown in FIG. 30 is an operation sequence in which the basic sequence of operations between the calling device, the calling fixed IMS network 20, and the called mobile IMS network 30, when a data communication-only terminal actually exists as the called device, follows pattern 5 of the basic sequence shown in FIG. 25.

The operations F1 to F4 in the operation sequence No. 5 shown in FIG. 30 are the same as the operations F1 to F4 in the operation sequence No. 1 shown in FIG. 26. Note that as the SDP parameters included in the INVITE request, the above SDP for IPv4 is described for the determination SDP parameters (note that the network protocol is IPv4).

In the fifth operation sequence shown in FIG. 30, following the operation of F4, a code 488 Not Acceptable Here response is returned from the terminating mobile IMS network 30 to the telephone number research device 10 (specifically, the message exchange control unit 12) via the originating fixed IMS network 20, indicating that acceptance has been rejected by the terminating device in the SIP session (F5, F6).

In this case, the telephone number investigation determination unit 13 of the telephone number investigation device 10 determines that a data communication-only terminal actually exists as the IMS terminal 50 to be investigated on the receiving side (i.e., the telephone number of the IMS terminal 50 to be investigated actually exists).

Then, the message exchange control unit 12 of the telephone number investigation device 10 returns an ACK (Acknowledgment) response indicating an acknowledgment response in the SIP session to the destination mobile IMS network 30 via the originating fixed IMS network 20 (F7, F8). This ends the session related to the INVITE request from the telephone number investigation device 10.

(Method of investigating telephone numbers)
FIG. 31 shows a summary of a method for investigating the usage status (specifically, existence (free, busy), and missing number) of a telephone number of an IMS terminal 50 (specifically, for example, the telephone number of a mobile phone having a 0A0 type telephone number or a terminal dedicated to data communication) based on the above-mentioned operational sequence.

Regarding the usage status of telephone numbers of mobile phones and data communication-only terminals with 0A0 type telephone numbers (specifically, for example, 090, 080, and 070) of IMS terminal 50 connected to a telecommunications operator (in other words, a communications carrier), it is possible to accurately determine whether the number is real (free, busy) or missing by describing IPv4 as the network protocol (in other words, Internet Protocol, IP version) among the SDP parameters and making an SDP offer (i.e., INVITE request) using SDP for IPv4 for other SDP parameters.

(Phone number investigation program)
As an example of a specific configuration aspect of the telephone number investigation program of the present invention, the telephone number investigation program of the embodiment is a program implemented in a telephone number investigation device 10 (see Figures 1 and 13) connected via an originating fixed IMS network 20 to a plurality of IMS terminals 50 connected to a terminating mobile IMS network 30.

The telephone number investigation program according to the embodiment is configured to cause a computer (specifically, a telephone number investigation device 10) connected to a plurality of IMS terminals 50 connected to a terminating mobile IMS network 30 via an originating fixed IMS network 20 to execute at least the following processes: adding SDP parameters to an INVITE request for the IMS terminal 50 being investigated and sending the INVITE request to the originating fixed IMS network 20 (toward the IMS terminal 50 being investigated); receiving a response message via the originating fixed IMS network 20; and determining the usage status of the telephone number of the IMS terminal 50 being investigated according to the response message.

The telephone number investigation program according to the embodiment is configured so that the SDP parameters are described as follows: the network protocol is IPv4, the media type is audio only, the media transport protocol is RTP/AVP only, and the audio codec includes G.711 μ-law and G.722 (i.e., SDP for IPv4).

(Telephone number information system)
FIG. 32 is a system configuration diagram of a telephone number information providing system 100 according to an embodiment, as an example of a specific configuration mode of the telephone number information providing system according to the present invention.

The telephone number information provision system 100 according to the embodiment includes one or more user terminals 90, and a telephone number research server (specifically, a telephone number research device 10) that is connected to the user terminals 90 via an IP network 80 and is also connected to a network not shown (e.g., a calling fixed IMS network 20).

The telephone number information provision system 100 according to the embodiment has a telephone number investigation server (specifically, telephone number investigation device 10) and a user terminal 90, and includes a network interface unit 11 that, when the telephone number investigation server (specifically, telephone number investigation device 10) receives a telephone number investigation information provision request for an IMS terminal 50 from the user terminal 90, transmits the telephone number usage status of the IMS terminal 50 determined by the telephone number investigation determination unit 13 to the user terminal 90 that has made the telephone number investigation information provision request via the IP network 80 (see FIG. 13).

When the telephone number investigation server (specifically, telephone number investigation device 10) receives a telephone number investigation information request for the telephone number being investigated from the user terminal 90 via the IP network 80, it refers to a recording medium (specifically, telephone number history database 15) in which telephone number history information is stored in chronological order, with a timestamp indicating the date and time of each telephone number usage status determination result being assigned, and transmits the telephone number history information via the IP network 80 to the user terminal 90 that made the telephone number investigation information request.

The recording medium on which the telephone number history information is stored (specifically, telephone number history database 15) may be distributed separately to users who need it. The recording medium on which the telephone number history information is stored (telephone number history database 15) is a recording medium on which the existence or non-existence of the telephone number being investigated is recorded, for example, generated by telephone number investigation device 10 connected to the telecommunications carrier network via a dedicated line, and may be used for searches in the system to which it is distributed.

The recording medium in which the telephone number history information is stored (specifically, telephone number history database 15) is a collection of results of validity judgments on the usage status of the telephone number of the receiving telephone terminal (specifically, a mobile phone or a terminal dedicated to data communication as an IMS terminal 50), and for example, each judgment result is given a timestamp indicating the date and time of judgment and is recorded in chronological order.

The distribution of the recording medium on which the telephone number history information is stored (specifically, telephone number history database 15) is not limited to distribution in the form of a database recorded on a DVD or hard disk, but also includes distribution using a communication line.

(Action and Effect)
The telephone number research device 10 according to the embodiment makes it possible to use an IMS interconnection interface or the like for interconnection between carriers to realize an accurate research of the usage status of telephone numbers in the terminating mobile IMS network 30. Therefore, by introducing a telephone number research tool based on the SIP protocol that can be UNI connected to the originating fixed IMS network 20, a smooth transition to the new system platform becomes possible.

The telephone number investigation device 10 according to the embodiment also makes it possible to accurately determine whether the telephone number of the IMS terminal 50 is in use (valid (actual)) or not in use (invalid (missing)). Therefore, by introducing a SIP protocol-based telephone number investigation tool that can be UNI connected to the originating fixed IMS network 20, a smooth transition to the new system platform becomes possible.

According to the telephone number investigation program of the embodiment, the telephone number investigation device 10 sequentially reads and executes the program recorded in memory (not shown), thereby enabling accurate investigation of telephone number usage in the terminating mobile IMS network 30 by using an IMS interconnection interface for inter-operator interconnection. Therefore, by introducing a SIP protocol-based telephone number investigation tool that can be UNI connected to the originating fixed IMS network 20, a smooth transition to the new system platform becomes possible.

According to the telephone number information provision system 100 of the embodiment, it is possible to provide a user who needs the information on whether a telephone number is in use (valid (actual)) or not in use (invalid (missing)) as determined by the telephone number investigation device 10. In addition, by distributing a recording medium (specifically, telephone number history database 15) on which telephone number history information is stored to a user who needs the information, it is possible to utilize the information on the user side, and to provide information that is useful, for example, in credit.

Although the embodiments of the present invention have been described above, the specific configuration of the present invention is not limited to the above-mentioned embodiments, and the present invention also includes modifications and changes to the above-mentioned embodiments that do not deviate from the gist of the present invention.

For example, in the above embodiment, IPv4 is described (in other words, used) as the network protocol (in other words, Internet Protocol, IP version) as an SDP parameter and offered, but IPv6 may also be described as the network protocol and offered. In this case, too, by describing the SDP parameters as follows, the same basic sequence and operation sequence as in the above embodiment will be obtained.

Specifically, when an offer is made by describing (in other words, using) IPv6 as the network protocol (in other words, Internet Protocol, IP version) among the SDP parameters for determination, the other SDP parameters for determination are described as follows.
○ Media type: audio only ○ Media transport protocol: RTP/AVP only ○ Audio codec: G.711 μ-law only

REFERENCE SIGNS LIST 10 Telephone number investigation device 11 Network interface unit 12 Message exchange control unit 13 Telephone number investigation determination unit 14 Telephone number history generation unit 15 Telephone number history database 20 Calling side fixed IMS network 20a SIP server 21 Calling side IBCF
30 terminating mobile IMS network 30a SIP server 30b SIP server 30c SIP server 31 terminating IBCF
50 IMS terminal 50a IMS terminal 50b IMS terminal 50c IMS terminal 90 User terminal 100 Information providing system

Claims (11)

A telephone number research device connected to a plurality of IMS terminals connected to a destination mobile IMS network via a source fixed IMS network,
a message exchange control unit that adds an SDP parameter to an INVITE request for the IMS terminal to be investigated, transmits the INVITE request to the originating fixed IMS network, and receives a response message via the originating fixed IMS network;
a telephone number investigation determination unit that determines a usage status of the telephone number of the IMS terminal to be investigated in response to the response message,
The SDP parameters are described as: network protocol is IPv4, media type is audio only, media transport protocol is RTP/AVP only, and audio codec includes G.711 μ-law and G.722;
By simultaneously offering G.711 μ-law and G.722 for the voice codec, the response from the receiving side when the IMS terminal to be surveyed is a missing number is code 404 Not Found, which is different from the response from the receiving side when the IMS terminal to be surveyed actually exists when only G.711 μ-law is offered for the voice codec, code 183 Session Progress, making it possible to determine whether the IMS terminal to be surveyed is a missing number or an actual terminal.
A telephone number investigation device characterized by: The telephone number investigation determination unit,
If the response message is code 183 Session Progress, code 180 Ringing, code 487 Request Terminated, code 488 Not Acceptable Here, code 500 Server Internal Error, or code 486 Busy Here, it is determined that the telephone number of the IMS terminal being investigated is real;
If the response message is a code 404 Not Found, it is determined that the telephone number of the IMS terminal to be investigated is a missing number.
2. The telephone number investigation device according to claim 1, If the response message is code 183 Session Progress or code 180 Ringing,
The telephone number investigation determination unit determines that the telephone number of the IMS terminal to be investigated is real,
the message exchange control unit transmits a CANCEL request to the originating fixed IMS network, thereby stopping ringing of the call bell of the IMS terminal to be investigated when a anonymous call rejection service and an anonymous call rejection function are not set for the IMS terminal to be investigated;
2. The telephone number investigation device according to claim 1, A telephone number investigation method for investigating the usage status of telephone numbers of IMS terminals to be investigated using a device connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network, comprising:
The apparatus,
adding SDP parameters to an INVITE request for the IMS terminal to be investigated, and sending the INVITE request to the originating fixed IMS network;
receiving a response message via the originating fixed IMS network;
determining a usage status of the telephone number of the IMS terminal being surveyed in response to the response message;
The SDP parameters are described as: network protocol is IPv4, media type is audio only, media transport protocol is RTP/AVP only, and audio codec includes G.711 μ-law and G.722;
By simultaneously offering G.711 μ-law and G.722 for the voice codec, the response from the receiving side when the IMS terminal to be surveyed is a missing number is code 404 Not Found, which is different from the response from the receiving side when the IMS terminal to be surveyed actually exists when only G.711 μ-law is offered for the voice codec, code 183 Session Progress, making it possible to determine whether the IMS terminal to be surveyed is a missing number or an actual terminal.
A method for investigating telephone numbers. A telephone number investigation method for investigating the usage status of telephone numbers of IMS terminals to be investigated using a device connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network, comprising:
The apparatus,
adding SDP parameters to an INVITE request for the IMS terminal to be investigated, and sending the INVITE request to the originating fixed IMS network;
receiving a response message via the originating fixed IMS network;
determining a usage status of the telephone number of the IMS terminal being surveyed in response to the response message;
The SDP parameters are described as follows: network protocol is IPv6, media type is audio only, media transport protocol is RTP/AVP only, and audio codec is G.711 μ-law only;
By describing IPv6 as the network protocol and offering only G.711 μ-law as the voice codec, the response from the receiving side when the IMS terminal to be surveyed is a missing number is code 404 Not Found, and by describing IPv4 as the network protocol and offering only G.711 μ-law as the voice codec, the response from the receiving side when the IMS terminal to be surveyed actually exists is different from code 183 Session Progress, so that it is possible to determine whether the IMS terminal to be surveyed is a missing number or an actual one.
A method for investigating telephone numbers. If the response message is code 183 Session Progress, code 180 Ringing, code 487 Request Terminated, code 488 Not Acceptable Here, code 500 Server Internal Error, or code 486 Busy Here, it is determined that the telephone number of the IMS terminal being investigated is real;
If the response message is a code 404 Not Found, it is determined that the telephone number of the IMS terminal to be investigated is a missing number.
6. The method for investigating a telephone number according to claim 4 or 5. If the response message is code 183 Session Progress or code 180 Ringing,
determining that the telephone number of the IMS terminal being investigated is real;
sending a CANCEL request to the originating fixed IMS network, stopping ringing of the call bell of the IMS terminal to be investigated when a anonymous call rejection service and a anonymous call rejection function are not set for the IMS terminal to be investigated;
6. The method for investigating a telephone number according to claim 4 or 5. A computer connected to a plurality of IMS terminals connected to a terminating mobile IMS network via an originating fixed IMS network,
a process of adding an SDP parameter to an INVITE request for the IMS terminal to be investigated and transmitting the INVITE request to the originating fixed IMS network;
receiving a response message via the originating fixed IMS network;
and determining a usage status of the telephone number of the IMS terminal to be surveyed in response to the response message;
The SDP parameters are described as: network protocol is IPv4, media type is audio only, media transport protocol is RTP/AVP only, and audio codec includes G.711 μ-law and G.722;
By simultaneously offering G.711 μ-law and G.722 for the voice codec, the response from the receiving side when the IMS terminal to be surveyed is a missing number is code 404 Not Found, which is different from the response from the receiving side when the IMS terminal to be surveyed actually exists when only G.711 μ-law is offered for the voice codec, code 183 Session Progress, making it possible to determine whether the IMS terminal to be surveyed is a missing number or an actual terminal.
A telephone number research program comprising: If the response message is code 183 Session Progress, code 180 Ringing, code 487 Request Terminated, code 488 Not Acceptable Here, code 500 Server Internal Error, or code 486 Busy Here, it is determined that the telephone number of the IMS terminal being investigated is real;
If the response message is a code 404 Not Found, it is determined that the telephone number of the IMS terminal to be investigated is a missing number.
9. The telephone number research program according to claim 8. If the response message is code 183 Session Progress or code 180 Ringing,
determining that the telephone number of the IMS terminal being investigated is real;
sending a CANCEL request to the originating fixed IMS network, stopping ringing of the call bell of the IMS terminal to be investigated when a anonymous call rejection service and a anonymous call rejection function are not set for the IMS terminal to be investigated;
9. The telephone number research program according to claim 8. A telephone number investigation device according to any one of claims 1 to 3;
A user terminal,
the telephone number investigation device includes a network interface unit that, when receiving a telephone number investigation information provision request for the IMS terminal from the user terminal, transmits the telephone number usage status of the IMS terminal determined by the telephone number investigation determination unit to the user terminal that has made the telephone number investigation information provision request via an IP network;
A telephone number information providing system comprising: