JP5224036B2 - Emergency call processing device, method, program, server device and emergency call processing system using the same - Google Patents

Description

  The present invention relates to an emergency call processing device, a method, a program, a server device, and an emergency call processing system using the same, and more particularly, a terminal accompanying movement of a third-generation mobile phone or the like using IMS (IP Multimedia Subsystem). The present invention relates to a method for holding an emergency call line in a system that provides a circuit switching service.

  With the recent increase in the use of mobile phones and IP (Internet Protocol) phones, the ratio of emergency calls from these telephone terminals to emergency organizations has also increased. In relation to this, various systems and methods have been proposed for processing related to emergency calls such as securing a line between a telephone terminal and an emergency organization and re-calling from the emergency organization to the phone terminal.

  For example, in Patent Document 1, even when an on-hook operation is performed at a telephone terminal talking to an emergency organization, a session between the terminal side and the exchange side is ignored by the terminal-side gateway device ignoring the on-hook signal. An Internet telephone system is described in which line holding and call back can be performed by maintaining the above.

  Further, in Patent Document 2, when the number on the called side is a preset telephone number, the disconnection signal transmitted from the calling side is not transmitted to the called side, but the connection line of the public line network is held and the call is disconnected. An IP telephone call back system is described in which a call back signal is sent back to the caller based on the signal. According to this, it is possible to perform call back processing by an instruction from the relay server when disconnecting from the originating terminal, and by securing the IP telephone terminal line on the relay server side, it is possible to maintain and recall the line necessary for emergency calls Can be realized.

  Patent Documents 1 and 2 described above relate to call processing of an emergency call between a fixed-use IP phone and an emergency organization, and are used in a fixed network. For this reason, it cannot be applied to the processing of an emergency call transmitted from a terminal such as a mobile phone that is mobilely used via a mobile network (mobile network).

  On the other hand, regarding call processing for emergency calls between mobile phones that are used for mobile use and emergency organizations, for example, according to 3rd Generation Partnership Project (3GPP) which is a standardization organization of W-CDMA (Wideband-Code Division Multiple Access) system Known to use "IMS (IP Multimedia Subsystem)" based on IP (Internet Protocol) technology that is being standardized by 3GPP TS 23.167 V7.6.0 (Non-Patent Document 1) It has been.

  Here, an outline of IMS will be briefly described.

  The introduction of IMS is being studied with the aim of replacing the conventional circuit switching core network with a new core network based on IP technology (see, for example, Non-Patent Document 2). IMS employs SIP (Session Initiation Protocol) as a call control protocol. In addition to CSCF (Call Session Control Function), which is the core of the IMS, the IMS has a function of holding the location information and profile (service contract information) of the subscriber of the terminal. ) And MGCF (Media Gateway Control Function) that performs protocol conversion between SIP signals and ISUP signals. Among them, the CSCF includes P (Proxy) -CSCF, S (Serving) -CSCF, and I (Interrogating) -CSCF elements, and further, E (Emergency)-, which will be described later, for emergency calls. CSCF is also specified.

  The simplest device configuration of IMS is composed of P-CSCF, S-CSCF, and HSS. The S-CSCF is a device that provides a service, and is specified by the HSS at the time of location registration from a subscriber's terminal. While the location registration period of the terminal is valid, the service control of the subscriber of the terminal is performed by the S-CSCF designated by the HSS. The P-CSCF performs signal transmission and reception and terminal authentication between the terminal and the S-CSCF.

  As a call control procedure by IMS, the terminal needs to perform location registration in advance. Through the location registration procedure, the terminal registers the correspondence between its own address (user identifier: usually a telephone number) and the IP address in the HSS. In a specific location registration procedure, the terminal resolves the IP address of the P-CSCF by DNS (Domain Name System) or the like, and transmits a SIP “REGISTER” signal to the P-CSCF based on the IP address. Upon receiving the “REGISTER” signal, the P-CSCF authenticates the terminal based on this signal, inquires the HSS about which S-CSCF to route to, and based on the response, the IP of the S-CSCF that is the routing destination An address is acquired, and a “REGISTER” signal is transmitted to the S-CSCF based on the IP address. When the S-CSCF receives the “REGISTER” signal, the S-CSCF holds the subscriber's profile by downloading from the HSS based on this signal, and holds the correspondence between the terminal address and the IP address of the P-CSCF in the memory.

  In the calling procedure performed after the location registration procedure, the calling terminal (calling terminal) transmits an SIP “INVITE” signal to the P-CSCF. When the P-CSCF receives the “INVITE” signal, the P-CSCF inquires to the HSS which S-CSCF the originating terminal should be controlled based on this, and obtains an appropriate S-CSCF IP address from the response. Based on the IP address, an “INVITE” signal is transmitted to the S-CSCF. When the S-CSCF receives the “INVITE” signal, the S-CSCF inquires of the HSS which terminal S-CSCF is controlled by the terminal on the basis of the “INVITE” signal. The IP address of the destination S-CSCF is acquired, and an “INVITE” signal is transmitted to the destination S-CSCF. When the destination S-CSCF receives the “INVITE” signal, the destination S-CSCF determines the destination P based on the correspondence between the address of the destination terminal and the IP address of the destination P-CSCF (the destination P-CSCF). -Determine the CSCF and send an "INVITE" signal to the destination P-CSCF. Upon receiving the “INVITE” signal, the destination P-CSCF specifies the address of the destination terminal based on this signal, and transmits the “INVITE” signal to the destination terminal based on the address.

  The above is an example of a simple configuration of IMS and a call control procedure. When the destination terminal is connected to the telephone network instead of the IMS network, the telephone network Only ISUP (ISDN User Part) signals, which are signaling protocols used between telephone network exchanges, can be interpreted based on the 7 common line signaling system (abbreviated as “SS7”, “C7”, “SSC7”). For this reason, the S-CSCF transmits an “INVITE” signal to the MGCF which is a gateway device between the IMS network and the telephone network.

  When the MGCF receives the “INVITE” signal, the MGCF performs SIP-ISUP conversion on the signal, and transmits the converted ISUP signal to the telephone network exchange. Conversely, when the MGCF receives an ISUP signal from the telephone network, it converts it into a SIP signal. In the case of an incoming call from the telephone network to the IMS network, the MGCF receives an ISUP “IAM (Initial Address Message)” signal, but since the MGCF has no interface with the HSS, the S-CSCF controls the destination terminal. Cannot be recognized. Therefore, an SIP “INVITE” signal is transmitted to the I-CSCF, whereby the I-CSCF inquires the HSS about an appropriate S-CSCF, and an “INVITE” signal is transmitted to the S-CSCF.

  Normally, the service is provided by the S-CSCF. However, when a more advanced service is provided, the service control is realized by an AS (Application Server) connected to the IMS. In this case, the “INVITE” signal is transmitted from the S-CSCF to the AS, the “INVITE” signal is edited in the AS, and then the “INVITE” signal is transmitted to the S-CSCF.

  Next, an outline of 3GPP TS 23.167 V7.6.0 will be described.

  3GPP TS 23.167 V7.6.0 is a document that describes necessary elements (functions) for realizing an emergency call in IMS. According to this, E-CSCF is defined as a CSCF for emergency calls. The major functions of the E-CSCF are the function to obtain the address of the appropriate emergency organization terminal from the location information of the calling terminal, and the LRF (Location Retrieval Function) when the location information of the calling terminal cannot be obtained. And a function for inquiring location information of the calling terminal.

  In this case, in order to realize an emergency call by IMS, in the location registration procedure, the terminal performs location registration using the emergency call public user identifier instead of the above-described normal user identifier (corresponding to a telephone number). In the call origination procedure, when an emergency call session is established, the emergency call session identifier is placed on the SIP “INVITE” signal in the IMS network in response to the emergency call signal from the calling terminal of the mobile network. To be transferred. When the P-CSCF receives the “INVITE” signal, the P-CSCF transmits an “INVITE” signal to the E-CSCF instead of the S-CSCF. When the E-CSCF receives the “INVITE” signal, the E-CSCF obtains the address of the emergency organization serving as the destination terminal based on the “INVITE” signal, and transmits the “INVITE” signal to the MGCF connected to the emergency organization based on the address. To do. Thereafter, as described above, the MGCF performs SIP-ISUP conversion, transmits the converted ISUP signal to the telephone network, and causes the terminal of the emergency organization to receive the call.

In this case, the recall from the terminal of the emergency organization to the caller's terminal is made by a normal call procedure toward the user identifier (corresponding to a telephone number) of the caller's terminal.
JP 2004-363818 A JP-A-2005-354441 3GPP TS 23.167 V7.6.0 (2007-09), 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; IP Multimedia Subsystem (IMS) emergency sessions (Release 7) Atsuo Kawamura, Toshiyuki Tamura, Tsutomu Tsukagoshi, Toshiaki Hasumi, Kazuo Watanabe, “Next Generation (FMC) Core Network”, NEC Technical Journal, Vol. 59, no. 2, 2006, p. 29-32

  In the above 3GPP TS 23.167 V7.6.0, it is only defined that the emergency agency is notified of a user identifier (telephone number etc.) that can be connected to the caller when a call is made to the emergency agency. There is no standardization on how to increase the reliability of the connection when recalling. In other words, since recalling from the emergency organization to the caller's terminal is a call to the caller similar to a normal call, depending on the network conditions, sufficient resources for the call may not be obtained, and connection may not be possible. It was.

  An object of the present invention is to provide an emergency call processing system capable of increasing the reliability of a recall connection from an emergency organization by line holding in a system for processing an emergency call between a mobile terminal and an emergency organization. It is to provide.

To achieve the above object, an emergency call processing device according to the present invention sends an emergency call between a mobile terminal and an emergency organization via IP-CAN (IP Connectivity Access Network) and IMS (IP Multimedia Subsystem). And an apparatus used in the system for processing , wherein a line between the terminal and the emergency agency is connected between the terminal and the IP-CAN and the IMS when an emergency call is transmitted from the terminal to the emergency agency. A line establishing means for separating and establishing a terminal side line and an emergency engine side line between the IMS and the emergency organization , and releasing the terminal side line when the emergency call is disconnected from the terminal side And the line holding means for holding the line on the emergency organization side, and the emergency organization side using the line on the emergency organization side that is held when the emergency call is recalled from the emergency organization to the terminal after the emergency call is disconnected. And having a recall means for terminating the serial terminal.

The emergency call processing method according to the present invention is a method of processing an emergency call between a mobile terminal and an emergency organization via an IP-CAN (IP Connectivity Access Network) and IMS (IP Multimedia Subsystem). And
When an emergency call is transmitted from the terminal to the emergency organization, a line between the terminal and the emergency organization is set between the terminal-side line between the terminal, the IP-CAN, and the IMS, and between the IMS and the emergency organization. A circuit establishment step for separating and establishing the circuit on the emergency agency side of
A line holding step of releasing the terminal side line and holding the emergency organization side line when the emergency call is disconnected from the terminal side;
A recalling step for receiving an incoming call from the emergency organization to the terminal using the line on the emergency organization side that is put on hold when the emergency organization is recalled from the emergency organization after the emergency call is disconnected. To do.

  ADVANTAGE OF THE INVENTION According to this invention, in the system which processes the emergency call between the terminal used for movement and an emergency organization, the reliability of the connection of the recall from an emergency organization can be improved by line holding | maintenance.

  Next, the best mode for carrying out the emergency call processing system, method, and program according to the present invention will be described in detail with reference to the drawings.

  This embodiment will be described with reference to FIGS.

  This embodiment is applied to a system that uses IMS to provide a circuit switching service to a mobile terminal such as an existing third generation mobile phone. In this system, if the caller (reporter) calls the emergency organization and disconnects the calling party, or if the caller does not have enough information, the emergency organization can call back to the caller. There is a need. Therefore, in this embodiment, the line used at the time of disconnection is held, and the line is not recaptured at the time of recall. According to this, the reliability of the connection at the time of recall can be improved by holding the line used in the first call without disconnecting.

  FIG. 1 shows the overall configuration of an emergency call processing system according to the present embodiment.

  The emergency call processing system shown in FIG. 1 is connected to a public telephone network (not shown) from a third-generation mobile phone (hereinafter referred to as “mobile phone”) 10 on a mobile network (not shown) via an IMS network. It is installed in a notification system that can make emergency calls (eg, 110, 119, 118, etc. in Japan) to the emergency agency terminal (hereinafter referred to as “emergency organization”) 20 A system 30 for providing a circuit switching service to the mobile phone 10 (hereinafter referred to as a “circuit switching service providing system” for convenience) 30 and an IMS system 40 are provided.

  The IMS system 40 includes a CSCF (consisting of a P-CSCF 411, an S-CSCF 412, an I-CSCF 413, and an E-CSCF 414) 41, which is the core of the IMS, and a telephone network and an IMS network to which terminals of the emergency organization 20 are connected. MGCF 42, which is a gateway device having a function of performing SIP-ISUP conversion between them, and HSS 43 holding location information and profiles (service contract information) of subscriber terminals. Since CSCF 41, MGCF 42, and HSS 43 are the same as those described above, details thereof are omitted.

  The circuit switching service providing system 30 includes an IP-CAN (IP Connectivity Access Network) 31 that is an IP connection access network connected between the mobile phone 10 and the IMS system 40, and an emergency call processing device and a server device according to the present invention. The circuit switching service server (hereinafter, abbreviated as “CS-AS (Circuit Service Application Server”)) 32 is configured, and the IMS is connected by connecting the IP-CAN 31 and the CS-AS 32 to the IMS system 40. By using this, it is possible to provide a circuit switching service to the mobile phone 10.

  The IP-CAN 31 applies a protocol for signals transmitted to and received from the mobile phone 10 (in this example, “RANAP: Radio Access Network Application Part” used in the third-generation mobile phone, but is not limited to this). .) Is converted to SIP used in IMS. That is, the IP-CAN 31 converts the RANAP signal from the mobile phone 10 into a SIP signal and transmits it to the P-CSCF 411. On the other hand, the IP-CAN 31 converts the SIP signal from the P-CSCF 411 into a RANAP signal. Send to phone 10.

  The CS-AS 32 is a server that is activated by the E-CSCF 414 and performs control specific to the circuit switching service. That is, the CS-AS 32 has a function of executing processing corresponding to each means (line establishment means, line hold means, and recall means) of the present invention, receives a service activation request from the E-CSCF 414, and receives a mobile phone. 10 performs control specific to the circuit switching service and instructs the E-CSCF 414 to operate.

  FIG. 2 illustrates an internal configuration example of the CS-AS 32. As shown in the figure, the CS-AS 32 includes a control unit 321 and a memory unit 331.

  The memory unit 331 stores session information 332 and signal information element 333 that are line information. The session information 332 includes “key”, “Call-ID”, “TO”, “FROM”, “other party key”, “emergency call display”, and the like. The CS-AS 32 sets the dialog ID as “key” as the session information 332, information associated with the call, for example, call identifier, call direction (originating side, non-occurring side), dialog ID of the other side, The emergency call identifier and the like are set to “Call-ID”, “TO”, “FROM”, “other party key”, “emergency call display”, etc., and are stored in the memory unit 331 for management. The signal information element 333 includes information elements such as “Request-URI”, “TO”, “From”, and “Call-ID” included in the header of the SIP signal.

  The control unit 321 includes an emergency call control unit 322, a B2BUA (Back-to-Back User Agent) control unit 323, and a SIP protocol control unit 324.

  The emergency call control unit 322 uses the emergency call session identifier on the SIP signal sent via the IP-CAN 31, the P-CSCF 411, and the E-CSCF 414 when an emergency call is transmitted from the mobile phone 10, and the mobile phone 10 The emergency call of the telephone 10 is recognized, and when the emergency call is recognized, “emergency call display” is set in the session information 332 and held in the memory unit 331. Further, the emergency call control unit 322 instructs the B2BUA control unit 323 which SIP signal is to be output to which session. Further, the emergency call control unit 322 edits the signal information element 333 unique to the emergency call and stores it in the memory unit 331.

  The B2BUA control unit 323 captures / releases the SIP signal session information 332 when an emergency call is transmitted from the mobile phone 10, sets session information 332 other than the emergency call display, and stores the session information 332 in the memory unit 331. In addition, the B2BUA control unit 323 edits the signal information element 333 other than the emergency call specific and stores it in the memory unit 331.

  The SIP protocol control unit 324 controls transmission / reception of SIP signals, checks SIP protocol specifications, and assembles SIP signals from signal information elements 333 held in the memory unit 331.

  When the CS-AS 32 receives an SIP “INVITE” signal corresponding to the emergency call when the emergency call is transmitted from the mobile phone 10, the B2BUA control unit 323 causes the session information (key, Call-ID, TO, FROM, “Session 1” is set as the destination key, emergency call display, etc.) 332, and the “session 1” dialog ID of the “session 1” and its accompanying information (call identifier, Call directionality (occurrence side, non-occurrence side), dialog ID (session 2), emergency call identifier, etc. of the other side are held in the memory unit 331. Then, the CS-AS 32 newly captures the dialog ID for the emergency organization 20 that is the destination (management of payout of the dialog ID within the CS-AS 32), edits the signal for the emergency organization 20, and sets the session information (key , Call-ID, TO, FROM, partner key, emergency call display, etc.) 332 and dialog ID corresponding to “session 2” with the emergency organization 20 and accompanying information (call identifier, call direction ( The dialogue ID (session 1), the emergency call identifier, etc.) of the other party (occurrence side, non-occurrence side) are held in the memory unit 331.

  The CS-AS 32 includes information on “Session 1” for the mobile phone 10 on the calling side and the emergency organization on the receiving side among the session information 332 held in the memory unit 331 when the calling side is disconnected from the mobile phone 10. The other party dialog ID (dialog ID of “session 1”) in the information of “session 2” for 20 is deleted.

  The CS-AS 32 pays out the dialog ID for the mobile phone 10 on the caller side as the session information 332 in the memory unit 331 and recalls the dialog ID corresponding to “session 3” and its ID when recalling from the emergency organization 20 on the callee side. Accompanying information (call identifier, call direction (occurrence side, non-occurrence side), other party's dialog ID, emergency call identifier, etc.) is created and held in the memory unit 331 and the other party's dialog ID of “session 2” “Session 3” is set to “” and stored in the memory unit 331.

  In the above configuration, as shown in FIG. 1, when the mobile phone 10 makes a call with the emergency organization 20, the mobile phone 10, IP-CAN 31, P-CSCF 411, E-CSCF 414, CS-AS32, E-CSCF 414, MGCF 42, emergency organization Line paths (routes) are established in the order of 20.

  On the other hand, when a call is released from the mobile phone 10 side, all the lines constituting these paths are normally released. However, in this embodiment, the CS-AS 32 detects disconnection from the mobile phone 10 and the CS-AS 32 The line path between the E-CSCF 414, the MGCF 42, and the emergency organization 20 is not cut off and is held (see line holding section A1 in FIG. 1). Note that the path of the line between the mobile phone 10, the IP-CAN 31, the P-CSCF 411, the E-CSCF 414, and the CS-AS 32 is released in consideration of the movement of the mobile phone 10 in the area where the mobile phone 10 moves (the line in FIG. 1). Release interval A2).

  In this way, in this embodiment, when a call from the emergency organization 20 to the mobile phone 10 is performed, the line between the CS-AS 32 and the emergency organization 20 is held, so that the line is connected at the time of the recall. It is possible to prevent the call from being disabled due to the failure to capture.

  Next, the overall operation of this embodiment will be described with reference to FIGS.

  3 to 5 illustrate a series of sequences from the emergency call transmission of the mobile phone 10 through the caller side disconnection to the recalling of the emergency organization 20.

  First, an emergency call transmission sequence will be described. This outline is shown in FIG.

  3 and 4, when an emergency call is made from the reporter's mobile phone (calling terminal) 10 to the emergency organization 20, the mobile phone 10 sends a “setup” signal for call setting based on the mobile phone protocol. Is sent to the IP-CAN 31 (step S1).

  The IP-CAN 31 sends a “callproc” signal for accepting call setting based on the cellular phone protocol to the cellular phone 10 as the response message (step S2), and converts it into an SIP “INVITE” signal. "Signal is sent to the P-CSCF 411 (step S3). In this INVITE signal, the address (phone number etc.) of the mobile phone 10 is described in the “From” header indicating the address of the transmission source, and the address (phone number etc.) of the emergency organization 20 is described in the “To” header indicating the address of the destination. And an emergency call identifier indicating that the call is an emergency call is set.

  When the P-CSCF 411 receives the “INVITE” signal from the IP-CAN 31, it returns a “100 Trying” signal to the IP-CAN 31 as a response message (step S 4) and sends the “INVITE” signal to the E-CSCF 414. (Step S5). Similarly, when the E-CSCF 414 receives the “INVITE” signal from the P-CSCF 411, the E-CSCF 414 returns a “100 Trying” signal to the P-CSCF 411 as a response message (step S6) and sends the “INVITE” signal to the CS-CS-411. It is sent to the AS 32 (step S7) (refer to the signaling route indicated by the arrow in FIG. 6).

  Next, when the SIP protocol control unit 324 receives the “INVITE” signal from the E-CSCF 414, the CS-AS 32 returns a “100 Trying” signal as a response message to the E-CSCF 414 (step S6) and the emergency call. The control unit 322 recognizes that the call is made to the emergency engine 20 from the address of the emergency engine 20 described in the “To” header of the received “INVITE” signal.

  Then, the CS-AS 32 sets “session 1” as the session information 332 based on the received “INVITE” signal by the B2BUA control unit 323, and stores it in the memory unit 331. In this case, “Key”, “Call-ID”, “TO”, “FROM”, “Destination key”, and “Emergency call display” of “Session 1” include the dialog ID and call identifier of Session 1, respectively. Call directionality (occurrence side, non-occurrence side), dialog ID of the other party (in this example, dialog ID of “session 2”), and emergency call identifier are set.

  At the same time, the CS-AS 32 causes the B2BUA control unit 323 to associate the dialog ID for the emergency organization 20 (the “session 2” dialog) with the dialog ID of “session 1” based on the received “INVITE” signal. ID) is newly captured (dialog ID payout management in the CS-AS 32), signal editing for the emergency organization 20 is performed, and "session 2" is set as session information 332 and stored in the memory unit 331. . In this case, “Key”, “Call-ID”, “TO”, “FROM”, “Destination key”, and “Emergency call display” of “Session 2” include the dialog ID and call identifier of Session 2, respectively. Call directionality (occurrence side, non-occurrence side), dialog ID of the other party (in this example, dialog ID of “session 1”), and emergency call identifier are set.

  As a result, the CS-AS 32 performs a session on the emergency call line between the mobile phone 10 and the emergency organization 20 to the IP-CAN 31, the P-CSCF 411, the E-CSCF 414, and the CS-AS 32 on the mobile phone 10 side. Session 1 "and CS-AS 32, E-CSCF 414, MGCF 42 on the emergency engine 20 side, and" Session 2 "to the emergency engine 20 are established separately (see the routes of sessions 1 and 2 indicated by the bold lines in FIG. 6). ).

  When the above processing is completed, the CS-AS 32 uses the SIP protocol control unit 324 to send a SIP “INVITE signal” carrying the emergency call session identifier to the E-CSCF 414 (step S10). When the E-CSCF 414 receives the “INVITE” signal from the CS-AS 32, the E-CSCF 414 returns a “100 Trying” signal as a response message to the CS-AS 32 (step S11) and sends the INVITE signal to the MGCF 42 (step S12). . When the MGCF 42 receives the INVITE signal from the E-CSCF 414, the MGCF 42 returns a “100 Trying” signal to the E-CSCF 414 as a response message (step S13), and converts it into an ISUP “IAM (Initial Address Message)” signal. The message is sent to the emergency organization 20 of the telephone network and received (step S14) (refer to the signaling route indicated by the arrow in FIG. 6).

  Upon receiving the “IAM” signal from the MGCF 42, the emergency organization 20 returns an “ACM (Address Complete Message)” signal of ISUP to the MGCF 42 as a response message (step S15). Then, when receiving the “ACM” signal, the MGCF 42 sends a SIP “183 Session Progress” signal to the E-CSCF 414 (step S16). Thereby, the “183 Session Progress” signal is sent from the E-CSCF 414 to the IP-CAN 31 via the CS-AS 32, the E-CSCF 414, and the P-CSCF 411 (steps S17 to S20).

  Next, the emergency engine 20 sends an ISUP “CPG (Call Progress)” signal to the MGCF 42 (step S21). Then, when receiving the “CPG” signal, the MGCF 42 converts the signal into a SIP “180 Ringing” signal and sends it to the E-CSCF 414 (step S22). Thereby, the “180 Ringing” signal is sent from the E-CSCF 414 to the IP-CAN 31 via the CS-AS 32, the E-CSCF 414, and the P-CSCF 411 (steps S23 to S26). When receiving the “180 Ringing” signal, the IP-CAN 31 converts it into an “alert” signal for calling based on the cellular phone protocol, and sends it to the cellular phone 10 (step S27).

  Next, the emergency organization 20 sends an “ANM (Answer Message)” signal of ISUP to the MGCF 42 (step S28). Then, when receiving the “ANM” signal, the MGCF 42 sends a SIP “200 OK” signal to the E-CSCF 414 (step S29). Thereby, the “200 OK” signal is sent from the E-CSCF 414 to the IP-CAN 31 via the CS-AS 32, the E-CSCF 414, and the P-CSCF 411 (steps S30 to S33).

  Upon receiving the “200 OK” signal from the P-CSCF 411, the IP-CAN 31 converts it into a “conn” signal for response based on the cellular phone protocol, and sends it to the cellular phone 10 (step S34). An “Ack” signal is sent to the P-CSCF 411 (step S35). Thereby, the “Ack” signal is sent from the P-CSCF 411 to the MGCF 42 via the E-CSCF 414, the CS-AS 32, and the E-CSCF 414 (steps S36 to S39). Next, the mobile phone 10 sends a “conn ack” signal for response confirmation based on the mobile phone protocol (RANAP) to the IP-CAN 31 (step S40).

  By the emergency call transmission sequence described above, a session is established between the mobile phone 10 and the emergency organization 20 via the line, and communication by emergency notification is performed (step S41).

  Next, the emergency call originating side disconnection sequence after the session is established will be described. This outline is shown in FIG.

  Referring to FIG. 4, when the caller disconnects from the mobile phone 10 of the reporter, the mobile phone 10 sends a “disc” signal for disconnection based on the mobile phone protocol to the IP-CAN 31 (step S42).

  As a response message, the IP-CAN 31 sends a release signal “release” based on the cellular phone protocol to the cellular phone 10 (step S43), and converts it into a “BYE” signal that is a SIP disconnection request. -Send to CSCF 411 (step S44). Thus, the “BYE” signal is sent from the P-CSCF 411 to the CS-AS 32 via the E-CSCF 414 (steps S45 and S46) (see the signaling path indicated by the arrow in FIG. 7).

  When the SIP protocol control unit 324 receives the “BYE” signal, the CS-AS 32 returns a “200 OK” signal to the E-CSCF 414 as a response (step S47). Thereby, the “200 OK” signal is sent from the E-CSCF 414 to the IP-CAN 31 via the P-CSCF 411 (steps S48 and S49). Meanwhile, the mobile phone 10 sends a release completion “recom” signal based on the mobile phone protocol to the IP-CAN 31 (step S50).

  In parallel with this, the CS-AS 32 causes the B2BUA control unit 323 to select the other party dialog IDs (“session 1” information and “session 2” information among the session information 332 held in the memory unit 331). Session 1) is deleted, thereby releasing session 1 between the CS-AS 32 and the mobile phone 10 (step S51) (refer to the route of session 1 indicated by a dotted line in FIG. 7).

  Furthermore, regarding the “session 2” on the emergency organization 20 side, the CS-AS 32 sends an SIP signal including an indication of holding (holding indication) to the E-CSCF 414 by the SIP protocol control unit 324 (steps S51 and S52). . Here, as an example, the SIP signal including the hold display is assumed to be a SIP “INFO” signal, but not limited thereto, any signal may be used. In the case of using the “INFO” signal, as an example, the SIP signal including the hold display may be obtained by a method such as setting “Hold” in the “Hold” header of the extension header (Hold: Hold).

  When the E-CSCF 414 receives the “INFO” signal including the hold indication from the CS-AS 32, the E-CSCF 414 further sends the signal to the MGCF 42 (step S53). When MGCF 42 receives the “INFO” signal including the hold indication, MGCF 42 converts the SIP “INFO” signal into an ISUP “INF” signal, and the line is put on hold indicating that the caller has disconnected from the emergency organization 20 side. It is notified (step S55). Thereby, “session 2” between the CS-AS 32 and the emergency organization 20 is suspended (step S56) (refer to the route of session 2 indicated by the bold line in FIG. 7). Here, as an example of the emergency call disconnect hold display on the emergency organization 20 side by the “INF” signal, for example, when the setting code of the corresponding information element of the “INF” signal is “00”, “No display”, “01” "Emergency call on hold (hold)" when "10", "Recall from emergency organization (recall)" when "10", "Reply to emergency call (response)" when "11", etc. It may be set. In this case, by setting the setting code of the “INF” signal from the MGCF 42 to the emergency engine 20 to “01”, the release of “session 1” and the suspension of “session 2” due to disconnection on the calling side are notified.

  Next, the emergency call recall sequence after the caller side disconnection will be described. This outline is shown in FIG.

  Referring to FIG. 6, when the emergency organization 20 recalls the caller's mobile phone 10 after disconnecting the calling party, the emergency organization 20 sends an “INF” signal of ISUP to the MGCF 42 as a recall request ( Step S57). Here, in the example of the emergency call disconnection hold display described above, the setting code of the “INF” signal is set to “10” to make a recall request after disconnecting the calling party.

  When receiving the recall request “INF” signal from the emergency organization 20, the MGCF 42 converts it into a SIP signal including a recall indication and sends it to the E-CSCF 414 (steps S58 and S59). Here, the SIP signal including the recall display is assumed to be a SIP “INFO” signal as an example, but not limited to this, any signal may be used. In the case of using the “INFO” signal, as an example, a SIP signal including a recall display may be used by setting “Callback” in the “Hold” header of the extension header (Hold: Callback).

  Upon receiving the “INFO” signal including the recall indication from the MGCF 42, the E-CSCF 414 transmits the signal to the CS-AS 32 (Step S60).

  When the CS-AS 32 receives the “INFO” signal including the recall display from the E-CSCF 414 by the SIP protocol control unit 324, the B2BUA control unit 321 issues a dialog ID for the mobile phone 10 to the mobile phone 10 side. Create “Session 3” from CS-AS 32 to I-CSCF 413, S-CSCF 412, P-CSCF 411, and IP-CAN 31, and “Session 3” dialog ID of “Session 3” to “Parallel key” of “Session 2” And the dialog ID of “session 3” on the mobile phone 10 side is captured (step S61). Then, the CS-AS 32 causes the SIP protocol control unit 324 to place the address of the reporter on the “TO” header of the “INVITE” signal and transmit it to the I-CSCF 413 (step S60) (indicated by the arrow in FIG. 8). Signaling path reference).

  As a result, an “INVITE” signal is sent from the I-CSCF 413 to the IP-CAN 31 via the S-CSCF 412 and the P-CSCF 411 according to a normal calling procedure when using the I-CSCF 413 (see above). The “100 Trying” signal is sent back to the other party (steps S62 to S69).

  Upon receiving the “INVITE” signal from the P-CSCF 411, the IP-CAN 31 converts the signal into a “setup” signal based on the cellular phone protocol and sends it to the cellular phone 10 (step S70). (Refer to the signaling route indicated by the arrow in FIG. 8).

  Although the configuration of the embodiment has been described in detail above, the mobile phone 10, the emergency organization 20, the IP-CAN 31, the CSCF 41 (P-CSCF 411, S-CSCF 412, I-CSCF 413, E-CSCF 414) illustrated in FIGS. Since the MGCF 42 is well known to those skilled in the art, its detailed configuration is omitted.

  Next, the operation of the CS-AS 32 will be described using the flowchart shown in FIG.

  9A is an operation flow corresponding to the emergency call origination sequence shown in FIG. 6, FIG. 9B is an operation flow corresponding to the emergency call origination side disconnection sequence shown in FIG. 7, and FIG. ) Respectively show an operation flow corresponding to the emergency call recall sequence shown in FIG.

  First, in FIG. 9A, the CS-AS 32 is a SIP “INVITE” signal sent from the mobile phone 10 via the IP-CAN 31, P-CSCF 411, and E-CSCF 414 by the SIP protocol control unit 324. Is received (step St11), the emergency call control unit 322 refers to the TO header of the “INVITE” signal, and determines whether the destination is the address of the emergency organization 20 (step St12). As a result, when the destination is the address of the emergency organization 20 (YES), the CS-AS 32 causes the emergency call control unit 322 to execute the corresponding session information 332 (“session 1” on the mobile phone 10 side and the emergency organization 20 side). An emergency call is set in “session 2”) and stored in the memory unit 331 (step St13). On the other hand, when the destination is not the address of the emergency organization 20 (NO), the CS-AS 32 transmits an “INVITE” signal to the E-CSCF 414 by the SIP protocol control unit 324 (step St14).

  Next, in FIG. 9B, the CS-AS 32 receives the SIP “BYE” sent from the mobile phone 10 via the IP-CAN 31, the P-CSCF 411, and the E-CSCF 414 by the SIP protocol control unit 324. ”Signal (step St21), the emergency call control unit 322 refers to the corresponding session information 332 (“ session 1 ”) stored in the memory unit 331 in step St13, and determines whether or not the call is an emergency call. Determination is made (step St22). As a result, if the call is an emergency call (YES), the B2BUA control unit 323 and the SIP protocol control unit 324 return a “200 OK” signal to the P-CSCF 411 and the IP-CAN 31 via the E-CSCF 414, and the mobile phone “Session 1” on the 10 side is released (step S23), a SIP signal including a hold indication is transmitted to the MGCF 42 via the E-CSCF 414 (step St24), and “session 2” on the emergency organization 20 side is put on hold. On the other hand, if it is not an emergency call (NO), the CS-AS 32 performs a normal disconnection process by the B2BUA control unit 323 and the SIP protocol control unit 324 (step St25).

  Next, in FIG. 9C, when the CS-AS 32 receives the SIP signal including the recall display sent from the emergency engine 20 via the MGCF 42 and the E-CSCF 414 by the SIP protocol control unit 324 ( Step St31), the B2BUA control unit 323 and the SIP protocol control unit 324 create "Session 3" on the mobile phone 10 side, and transmit an "INVITE" signal to the I-CSCF 413 (Step St32). From the I-CSCF 413, The incoming call is made to the mobile phone 10 via the S-CSCF 412, the P-CSCF 411, and the IP-CAN 31.

  As described above, the present embodiment has the following effects.

  The first effect is that the emergency call line between the mobile phone 10 and the emergency organization 20 is held by the CS-AS 32, so that the reliability of the connection at the time of recall from the emergency organization 20 is improved. .

  The second effect is that the B2BUA control between the mobile phone 10 and the emergency organization 20 is performed by the B2BUA control unit 323 of the CS-AS 32, so that only the line for the caller can be released, and the caller is waiting for a recall. It is possible to prevent invalid line hold when the mobile station moves.

  The third effect is that the B2BUA control unit 323 of the CS-AS 32 performs B2BUA control between the mobile phone 10 and the emergency organization 20, so that even if the whistleblower moves in the waiting area, the recall is recalled. It is possible to do.

  In the above embodiment, the case where IMS is used is described. However, the present invention is not limited to this, and any device that can process an emergency call between a mobile terminal and an emergency organization can be used. Any communication network can be used. Also, mobile terminals are not limited to third-generation mobile phones, and can be applied to, for example, third-generation and later mobile phones.

  Further, the emergency call processing system according to the above embodiment is realized by CS-AS 32 (circuit switching service server), but each means (line establishing means, line holding means, and recalling means) of the present invention is used. As long as the corresponding processing can be executed, the physical configuration, the hardware (circuit) inside the system, and the software (program) configuration are not particularly limited. For example, it may be composed of one server machine or a plurality of server machines. Alternatively, an individual circuit, unit, or program component (program module, etc.) is configured independently for each means or function of the present invention, or is configured integrally in one circuit or unit, etc. It is also possible to provide this form. These forms can be appropriately selected according to circumstances such as the function and application of the system actually used.

  In addition, an emergency call processing method having steps for performing the same processing as these corresponding to each means of the present invention described above is also included in the scope of the present invention.

  Furthermore, when realizing at least a part of each means of the present invention described above by software processing by a computer such as a processor having a CPU (Central Processing Unit), a program (emergency call processing program) for causing the computer to function Are also included in the scope of the present invention. This program is not limited to a program in a format that can be directly executed by the CPU, but includes a program in various forms such as a source format program, a compressed program, and an encrypted program. In addition, this program operates in cooperation with a control program such as an OS (Operating System) and firmware that controls the entire system, or is incorporated in a part thereof and constitutes an application program that operates integrally. Any form such as a software component (software module) can be provided. Furthermore, this program can be downloaded from another server machine via a wireless or wired line, installed on a recording medium in its own system, and used. These forms can be appropriately selected according to circumstances such as the function and application of the system actually used.

  A computer-readable recording medium that records the above computer program is also included in the scope of the present invention. In this case, the recording medium can be provided in any form such as a memory such as a ROM (Read Only Memory) that is used in a fixed manner in the apparatus or a portable type that can be carried by the user. is there.

  The present invention can be applied to uses such as an apparatus, a method, a program, a server, and a system for providing a circuit switching service to a mobile phone using IMS.

1 is a schematic block diagram showing an overall configuration of an emergency call processing system according to an embodiment of the present invention. It is a schematic block diagram which shows the internal structure of CS-AS shown in FIG. It is a sequence diagram explaining the whole operation | movement of the emergency call processing system shown in FIG. FIG. 4 is a sequence diagram for explaining the overall operation of the emergency call processing system shown in FIG. 1 following FIG. 3. FIG. 5 is a sequence diagram for explaining the overall operation of the emergency call processing system shown in FIG. 1 following FIG. 4. It is a figure explaining the transmission sequence of the emergency call by the emergency call processing system shown in FIG. It is a figure explaining the calling party side disconnection sequence of the emergency call by the emergency call processing system shown in FIG. It is a figure explaining the recall sequence of the emergency call by the emergency call processing system shown in FIG. (A)-(c) is a flowchart explaining operation | movement of CS-AS corresponding to each sequence shown to FIGS.

Explanation of symbols

10 mobile phone 20 emergency organization 30 circuit switching service providing system 31 IP-CAN
32 CS-AS (Server for circuit switching service)
40 IMS system 41 CSCF
42 MGCF
43 HSS
321 Control unit 322 Emergency call control unit 323 B2BUA control unit 324 SIP protocol control unit 331 Memory unit 332 Session information 333 Signal information element 411 P-CSCF
412 S-CSCF
413 I-CSCF
414 E-CSCF

Claims (13)

An apparatus used in a system that processes an emergency call between a mobile terminal and an emergency organization via IP-CAN (IP Connectivity Access Network) and IMS (IP Multimedia Subsystem) ,
When an emergency call is transmitted from the terminal to the emergency organization, a line between the terminal and the emergency organization is set between the terminal-side line between the terminal, the IP-CAN, and the IMS, and between the IMS and the emergency organization. A circuit establishment means for establishing a separate line to the emergency agency side of
Line holding means for releasing the terminal side line and holding the emergency organization side line when the emergency call is disconnected from the terminal side;
Recalling means for receiving an incoming call from the emergency organization to the terminal by using the line on the emergency organization side that has been put on hold when the emergency organization is recalled from the emergency organization after the emergency call is disconnected. Emergency call processing device. The line establishment means, when an emergency call is transmitted from the terminal to the emergency organization, performs a session on the line via the IMS between the terminal and the emergency organization by B2BUA (Back-to-Back User Agent) control. The first session by the terminal side line and the second session by the emergency organization side line are established separately,
The line holding means releases the terminal side line in the first session and holds the emergency organization side line in the second session when the emergency call is disconnected from the terminal. ,
The recall means creates a third session on the terminal side line when the emergency call is recalled from the emergency organization using the line on the second session held on hold. The emergency call processing device according to claim 1, wherein the emergency call processing device causes the terminal to receive a call. The IMS includes P-CSCF (Proxy Call Session Control Function), S-CSCF (Serving Call Session Control Function), I-CSCF (Interrogating Call Session Control Function), E-CSCF (Emergency Call Session Control Function), and MGCF. (Media Gateway Control Function)
The terminal is connected to the IMS in a state capable of protocol conversion via an IP-CAN (IP Connectivity Access Network),
The emergency organization is connected to the IMS via the MGCF in a protocol-convertible state,
The line on the terminal side in the first session passes through the E-CSCF, the P-CSCF, and the IP-CAN,
The line on the emergency organization side in the second session is via the E-CSCF and the MGCF,
3. The emergency according to claim 2, wherein a line on the terminal side in the third session is routed through the I-CSCF, the S-CSCF, the P-CSCF, and the IP-CAN. Call processing device. A method of processing an emergency call between a mobile terminal and an emergency organization via IP-CAN (IP Connectivity Access Network) and IMS (IP Multimedia Subsystem) ,
When an emergency call is transmitted from the terminal to the emergency organization, a line between the terminal and the emergency organization is set between the terminal-side line between the terminal, the IP-CAN, and the IMS, and between the IMS and the emergency organization. A circuit establishment step for separating and establishing the circuit on the emergency agency side of
A line holding step of releasing the terminal side line and holding the emergency organization side line when the emergency call is disconnected from the terminal side;
A recalling step for receiving an incoming call from the emergency organization to the terminal using the line on the emergency organization side that is put on hold when the emergency organization is recalled from the emergency organization after the emergency call is disconnected. Emergency call processing method. The line between the terminal and the emergency organization is via IMS (IP Multimedia Subsystem),
In the line establishing step, when an emergency call is transmitted from the terminal to the emergency agency, a session via the IMS line between the terminal and the emergency agency is controlled by B2BUA (Back-to-Back User Agent) control. The first session by the terminal side line and the second session by the emergency organization side line are established separately,
The line holding step releases the terminal side line in the first session and holds the emergency side line in the second session when the emergency call is disconnected from the terminal. ,
The recall step creates a third session by the terminal side line when the emergency call is recalled from the emergency organization using the line by the held second session. 5. The emergency call processing method according to claim 4, wherein the terminal is caused to receive a call. The circuit establishment step includes:
When receiving a call signal from the terminal, determining whether the call signal is an emergency call;
And when the outgoing signal is an emergency call, setting an emergency call in the line information,
The line holding step includes:
When receiving a disconnection signal from the terminal, referring to the line information and determining whether the disconnection signal is an emergency call;
When the disconnection signal is an emergency call, the line on the terminal side is released and the line on the emergency organization side is suspended.
The recall step includes:
Reconstructing the released line on the terminal side when receiving a recall signal from the emergency agency to the terminal using the line on the emergency engine side that is put on hold;
6. The emergency call processing method according to claim 5, further comprising the step of receiving a recall signal from the emergency agency to the terminal using the emergency agency side line and the reconstructed terminal side line. . The circuit establishment step includes:
When receiving a transmission signal from the terminal, referring to the header of the transmission signal to determine whether the destination is the emergency organization;
If the destination is an emergency organization, session information is created by associating information on the first session on the terminal side line with information on the second session on the emergency organization side, and the session information is emergency Setting up a call and storing the session information;
The line holding step includes:
When receiving a disconnection signal from the terminal, referring to the stored session information and determining whether the disconnection signal is an emergency call;
If the disconnection signal is an emergency call, the information on the first session in the stored session information is deleted to release the terminal-side line, and the information on the second session Deleting the correspondence information with the first session and suspending the line on the emergency organization side,
The recall step includes:
When a recall signal is received from the emergency organization to the terminal using the suspended emergency agency side line, a third session by the terminal side line is associated with the information on the second session. Creating information about and reconstructing the released terminal-side line;
6. The emergency call processing method according to claim 5, further comprising the step of receiving a recall signal from the emergency agency to the terminal using the emergency agency side line and the reconstructed terminal side line. .   The IMS includes P-CSCF (Proxy Call Session Control Function), S-CSCF (Serving Call Session Control Function), I-CSCF (Interrogating Call Session Control Function), E-CSCF (Emergency Call Session Control Function), and MGCF. (Media Gateway Control Function)
  The terminal is connected to the IMS in a state capable of protocol conversion via an IP-CAN (IP Connectivity Access Network),
  The emergency organization is connected to the IMS via the MGCF in a protocol-convertible state,
  The line on the terminal side in the first session passes through the E-CSCF, the P-CSCF, and the IP-CAN,
  The line on the emergency organization side in the second session is via the E-CSCF and the MGCF,
  The line on the terminal side in the third session is routed through the I-CSCF, the S-CSCF, the P-CSCF, and the IP-CAN. The emergency call processing method according to any one of the above. A server device used in a system that processes an emergency call between a mobile terminal and an emergency organization via IP-CAN (IP Connectivity Access Network) and IMS (IP Multimedia Subsystem) ,
When an emergency call is transmitted from the terminal to the emergency organization, a line between the terminal and the emergency organization is set between the terminal-side line between the terminal, the IP-CAN, and the IMS, and between the IMS and the emergency organization. A circuit establishment means for establishing a separate line to the emergency agency side of
Line holding means for releasing the terminal side line and holding the emergency organization side line when the emergency call is disconnected from the terminal side;
A server device comprising: a recalling unit that enables recalling from the emergency organization to the terminal using a line on the emergency organization side that is reserved after the emergency call is disconnected.   The line establishment means, when an emergency call is transmitted from the terminal to the emergency organization, performs a session on the line via the IMS between the terminal and the emergency organization by B2BUA (Back-to-Back User Agent) control. The first session by the terminal side line and the second session by the emergency organization side line are established separately,
  The line holding means releases the terminal side line in the first session and holds the emergency organization side line in the second session when the emergency call is disconnected from the terminal. ,
  The recall means creates a third session on the terminal side line when the emergency call is recalled from the emergency organization using the line on the second session held on hold. The server device according to claim 9, wherein the server device is configured to receive a call to the terminal.   The IMS includes P-CSCF (Proxy Call Session Control Function), S-CSCF (Serving Call Session Control Function), I-CSCF (Interrogating Call Session Control Function), E-CSCF (Emergency Call Session Control Function), and MGCF. (Media Gateway Control Function)
  The terminal is connected to the IMS in a state capable of protocol conversion via an IP-CAN (IP Connectivity Access Network),
  The emergency organization is connected to the IMS via the MGCF in a protocol-convertible state,
  The line on the terminal side in the first session passes through the E-CSCF, the P-CSCF, and the IP-CAN,
  The line on the emergency organization side in the second session is via the E-CSCF and the MGCF,
  11. The server according to claim 10, wherein a line on the terminal side in the third session is routed through the I-CSCF, the S-CSCF, the P-CSCF, and the IP-CAN. apparatus. The server device according to any one of claims 9 to 11 ,
IMS (IP Multimedia Subsystem) connected to the server device;
An emergency call processing system comprising: The emergency call processing system according to claim 12 , further comprising an IP-CAN (IP Connectivity Access Network) that connects the IMS and the terminal so as to allow protocol conversion.

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