JP2011205188A - Apparatus and system for communication control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and system for communication control, capable of suppressing cost for terminal update and capital investment, by connecting an existing non-IMS (IP Multimedia Subsystem) terminal with an IMS supported system.SOLUTION: The communication control apparatus includes a terminal type memory unit 22 which keeps information of an IMS terminal 6 or a VoIP terminal 7 as terminal type information of a user terminal based on a session control message from the user terminal or a reception port, and a repeating unit 26 which relays a transceiving signal with the VoIP terminal 7 memorized in the terminal type memory unit 22 through mutual format conversion between an IMS signal format and a VoIP signal format and relays a transceiving signal with the IMS terminal 6 memorized in the terminal type memory unit 22 without performing format conversion.

Description

  The present invention relates to a communication control device and a communication control system used in IMS (IP Multimedia Subsystem).

  IMS is defined for the purpose of providing IP-based multimedia services such as voice and moving images regardless of fixed communication or mobile communication. In the IMS, session control is performed using SIP (Session Initiation Protocol) used in an IP phone or the like. In this IMS session control, three session control functions called P-CSCF (Proxy Call Session Control Function), S-CSCF (Serving Call Session Control Function), and I-CSCF (Interrogating Call Session Control Function) are used. The communication session is set and released, and the SIP signal is relayed.

JP 2009-206766 A

  By the way, IP telephones have been widely used so far due to rapid development of the Internet and cost reduction. In a VoIP (Voice over IP) system using an IP phone, session control is performed via a gateway device called SBC (Session Border Controller) and a session control device such as C5SS (Class 5 Soft Switch). The interface between the SBC or C5SS and the VoIP terminal or the subsequent relay device differs for each communication carrier. For this reason, a VoIP terminal that satisfies the specifications of the communication carrier is used.

  On the other hand, in the IMS described above, an interface between the user terminal, the P-CSCF, the I-CSCF, and the S-CSCF is strictly defined. For this reason, only user terminals that satisfy the IMS specifications can be used. Therefore, in order to migrate from the existing VoIP system to IMS, the user terminal of the end user must be replaced from the VoIP terminal to the IMS terminal, which increases the cost of terminal update and makes the user aware of equipment changes. It was.

  On the network side, all services provided by the existing VoIP system have to be migrated to IMS. In addition, when IMS is installed, it is common to have IMS equipment coexisting with the existing VoIP system, and the existing VoIP system and IMS equipment must be doubled. As described above, when shifting from the existing VoIP system to IMS, there is a problem that initial capital investment on the network side also increases.

  The present invention has been made in view of the above points, and by connecting an existing non-IMS terminal to an IMS-compatible system, a communication control apparatus capable of suppressing the cost of terminal update and network-side equipment investment, and An object is to provide a communication control system.

  A communication control apparatus according to the present invention is a communication control apparatus that performs communication control in an IMS-compatible system for user terminals including an IMS terminal and a non-IMS terminal, and the content or reception port of a user registration message from the user terminal For the transmission / reception signal between the terminal type storage unit holding the IMS terminal or the non-IMS terminal as the terminal type information of the user terminal and the non-IMS terminal stored in the terminal type storage unit, IMS A signal format and a non-IMS signal format are mutually converted and relayed, and a transmission / reception signal to / from an IMS terminal stored in the terminal type storage unit is provided with a relay unit that relays without performing the format conversion. It is characterized by that.

  According to this configuration, the transmission / reception signal between the communication control device and the non-IMS terminal is relayed after being mutually converted into the IMS signal format and the non-IMS signal format, so that the non-IMS terminal is replaced with an IMS-compatible system. Can be connected to. This eliminates the need to replace the user terminal from a non-IMS terminal to an IMS terminal when shifting from an existing non-IMS compatible system to an IMS compatible system. Therefore, the cost of updating the terminal can be eliminated and the user is not made aware of the equipment change on the network side. In addition, since the non-IMS terminal is connected to the IMS-compatible system, the facilities of the existing non-IMS-compatible system can be removed. For this reason, it is possible to make a transition from a non-IMS compatible system to an IMS compatible system in stages, without double installation of IMS compatible systems and non-IMS compatible systems, thereby reducing network equipment investment. can do.

  Also, in the communication control apparatus according to the present invention, the relay unit further relays the user terminal with a non-IMS compatible system, and when relaying with the non-IMS compatible system, the terminal type storage unit The transmission / reception signal to / from the non-IMS terminal is relayed without performing the format conversion, and the transmission / reception signal to / from the IMS terminal stored in the terminal type storage unit is subjected to the format conversion. It is characterized by relaying.

  According to this configuration, a non-IMS terminal can be connected to an IMS-compatible system and a non-IMS-compatible system. In addition, since transmission / reception signals between the communication control device and the IMS terminal are relayed after being mutually converted into an IMS signal format and a non-IMS signal format, the IMS terminal is converted into an IMS compatible system and a non-IMS compatible system. Can be connected to.

  In the communication control apparatus according to the present invention, the user registration message may be a REGISTER message conforming to SIP.

  In the communication control apparatus according to the present invention, the transmission / reception signal is a REGISTER, INVITE, or SUBSCRIBE request message that conforms to SIP, and the relay unit receives a non-IMS terminal stored in the terminal type storage unit. The authentication information is generated based on the received request message, and the format can be converted by adding the authentication information to the request message.

  Also, in the communication control apparatus according to the present invention, the transmission / reception signal is a response message to a REGISTER, INVITE, or SUBSCRIBE request message or INVITE or SUBSCRIBE request message that conforms to SIP, and the relay unit includes the terminal The format conversion can be performed by adding access network information indicating an access line connected to the non-IMS terminal to a request message or a response message with the non-IMS terminal stored in the type storage unit.

  Also, in the communication control apparatus according to the present invention, the transmission / reception signal is an INVITE or SUBSCRIBE request message that conforms to SIP, and the relay unit relays session control during user registration in the IMS-compatible system. The routing information for the relay device notified from the device is held, and the format can be converted by adding the routing information to the request message received from the non-IMS terminal stored in the terminal type storage unit.

  In the communication control apparatus according to the present invention, the transmission / reception signal is a SIP-compliant INVITE or SUBSCRIBE request message, and the relay unit is a request for a non-IMS terminal stored in the terminal type storage unit. The format can be converted by changing the sender information in the message to the sender information that can be processed by the non-IMS terminal.

  In the communication control apparatus according to the present invention, the transmission / reception signal is an INVITE message conforming to SIP or a response message to the INVITE message, and the relay unit communicates with a non-IMS terminal stored in the terminal type storage unit. The information about the media in the interim INVITE message or the response message can be converted into information about the media that can be processed by the non-IMS terminal.

  Further, the communication control system of the present invention comprises the above-described communication control device and an IMS-compatible management server connected to the communication control device and having a database in which information is registered in units of users. A user ID field in which a user ID of the user terminal is registered; an additional information field in which additional information related to the user terminal is registered; a user ID is registered in the user ID field; and the additional information field The group ID of the group to which the user terminal belongs is registered as additional information to associate the user ID with the group ID, the group ID is registered in the user ID field, and the group information is registered as additional information in the additional information field. By associating the group ID with the group information, Characterized in that associating the user ID and group information through the loop ID.

  According to this configuration, information can be registered in the database in units of groups without changing the data structure of the database that is restricted to information registration in units of users. For this reason, the database of the system corresponding to non-IMS which has the information of a group unit as well as the information of a user unit can be collected in the database corresponding to IMS. Further, since the basic structure of the database data structure is not changed when linked with the application server, it is not necessary to change the processing logic of the application.

  Another communication control system of the present invention is the IMS-compatible system comprising the communication control device and a management server having a database in which user information of the user terminal relayed from the communication control device is registered. The application server further includes a converter that converts an API (Application Programming Interface) for a non-IMS-compliant database into an API for an IMS-compliant database. An application is provided to the user terminal by referring to the database of the management server via an IMS compatible API by interface conversion.

  According to this configuration, it is possible to make the non-IMS compatible application server refer to the database of the IMS compatible management server. Therefore, a non-IMS compatible application server can be used as an IMS compatible application server. In addition, at the time of transition from a non-IMS compatible system to an IMS compatible system, the service of an existing application server can be continued in the IMS compatible system.

  According to the present invention, at the time of transition from an existing non-IMS compatible system to an IMS compatible system, the existing non-IMS terminal is connected to the IMS compatible system, thereby reducing the cost of updating the terminal and capital investment on the network side. be able to.

It is a figure which shows embodiment of this invention and is a system block diagram of a communication control system. It is a figure which shows embodiment of this invention and is a functional block diagram of a P-CSCF server. It is a figure which shows embodiment of this invention, and is a figure which shows an example (authentication information addition) of a format conversion process of a transmission / reception signal. It is a figure which shows embodiment of this invention, and is a figure which shows an example (access network information addition) of a format conversion process of a transmission / reception signal. It is a figure which shows embodiment of this invention, and is a figure which shows an example (routing information addition) of a format conversion process of a transmission / reception signal. It is a figure which shows embodiment of this invention, and is a figure which shows an example (caller number conversion) of a format conversion process of a transmission / reception signal. It is a figure which shows embodiment of this invention, and is a figure which shows an example (media codec information conversion) of a format conversion process of a transmission / reception signal. It is a figure which shows embodiment of this invention and is a figure which shows an example (resource control) of the format conversion process of a transmission / reception signal. It is a figure which shows embodiment of this invention and is a sequence diagram of a user registration process. It is a figure which shows embodiment of this invention and is a sequence diagram of a session control process. It is a figure which shows embodiment of this invention and is explanatory drawing of IMS conversion of the existing application server. It is a figure which shows embodiment of this invention and is explanatory drawing of the storage system of the shared database of a management server. It is a figure which shows embodiment of this invention and is explanatory drawing of the outgoing / incoming call control at the time of an emergency call.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present embodiment, a hybrid IMS that enables an IMS terminal and an existing VoIP terminal to be connected simultaneously will be described. Note that existing non-IMS terminals are not limited to VoIP terminals, but may be SIP terminals that can be aggregated into IMS. FIG. 1 is a system configuration diagram of a communication control system according to an embodiment of the present invention.

  The communication control system 1 shown in FIG. 1 has been migrated from an existing VoIP system, which is a non-IMS compatible system, to IMS, and is configured to be able to provide services to existing VoIP users and new IMS users. ing. The IMS network 2 of the communication control system 1 provides a communication service regardless of mobile communication or fixed communication. The IMS terminal 6 of the IMS user is connected via the first access network 3 and the second access is performed. A VoIP terminal 7 of an existing VoIP user is connected via the network 4.

  The first and second access networks 3 and 4 may be radio access networks such as LTE (Long Term Evolution), WLAN (Wireless LAN), WiMAX (Worldwide Interoperability for Microwave Access), etc., or FTTH ( It may be a wired network such as Fiber To The Home) or ADSL (Asymmetric Digital Subscriber Line).

  In this communication control system 1, the IMS terminal 6 is session-controlled using a SIP message that is a session control message corresponding to IMS. On the other hand, the VoIP terminal 7 that is a non-IMS terminal is session-controlled using a SIP message that is a session control message that does not support IMS. For this reason, in the IMS network 2, the SIP message that is not compatible with the IMS of the VoIP terminal 7 is converted into a SIP message that is compatible with the IMS to enable communication by the VoIP terminal 7.

  The IMS network 2 is connected to a soft switch 11 and an application server 12 that provide services of an existing VoIP system, and is connected to the existing telephone network 5 via the soft switch 11. Therefore, the VoIP terminal 7 can receive communication via the telephone network 5 and provision of a conventional application service. Further, the IMS network 2 is configured to be connectable to various servers of other communication systems compliant with IMS.

  The IMS network 2 includes a P-CSCF server 13, an I-CSCF server 14, an S-CSCF server 15, a management server 16, and an application server 17. The P-CSCF server 13 is connected to the IMS terminal 6 and the VoIP terminal 7 via the first and second access networks 3 and 4, and the IMS terminal 6 and the VoIP terminal 7, the S-CSCF server 15 and the I-CSCF server. The SIP message is relayed to and from 14. Further, the P-CSCF server 13 performs matching with the access network in order to make the IMS network 2 independent from various access networks. As the matching function of the P-CSCF server 13, the use efficiency of radio resources is increased by, for example, compression / decompression of SIP messages.

  Further, the P-CSCF server 13 identifies the IMS terminal 6 and the VoIP terminal 7 and performs a relay process according to the terminal type, thereby enabling the IMS terminal 6 and the VoIP terminal 7 to be connected to the IMS network 2. Yes. In this case, the P-CSCF server 13 includes a terminal type storage unit 22 that stores the terminal type of the user terminal, and identifies the IMS terminal 6 and the VoIP terminal 7 with reference to the terminal type storage unit 22. . Then, the P-CSCF server 13 relays the VoIP signal format and the IMS signal format with respect to each other for the SIP message with the VoIP terminal 7 stored as the non-IMS terminal in the terminal type storage unit 22. To do.

  That is, the SIP message transmitted from the VoIP terminal 7 is converted into the IMS signal format corresponding to IMS and relayed in the IMS network 2, and the SIP message for the VoIP terminal 7 is VoIP signal format corresponding to VoIP And is relayed to the VoIP terminal 7. On the other hand, the P-CSCF server 13 relays the SIP message with the IMS terminal 6 stored in the terminal type storage unit 22 without converting the format. Details of the format conversion process of the P-CSCF server 13 and the storage process to the terminal type storage unit 22 will be described later.

  The I-CSCF server 14 selects the S-CSCF server 15 suitable for the user by using the user information managed by the management server 16 at the time of user registration in the IMS and session control. Then, the I-CSCF server 14 takes over the user registration process to the selected S-CSCF server 15. Moreover, the I-CSCF server 14 hides the configuration in the IMS network 2 as a gateway from another network.

  The S-CSCF server 15 performs session control and authentication using user information managed by the management server 16. Further, the S-CSCF server 15 activates service processing of the application server 17 as necessary. In this way, the S-CSCF server 15 functions as a central server when providing services to users.

  The management server 16 is a so-called HSS (Home Subscribe Server) and manages a shared database 21 in which user information necessary for session control and service control is stored. The shared database 21 stores private user identifiers, public user identifiers, S-CSCF server 15 selection information, contract service information, user authentication information, and the like as user information. In addition, the shared database 21 includes a database that the application server 12 of the existing VoIP system has.

  The application server 17 provides an application service to the IMS terminal 6 and the VoIP terminal 7 in response to the SIP message relayed from the S-CSCF server 15. Further, the application server 17 acquires user information related to the application service from the shared database 21 of the management server 16.

  The application server 12 of the existing VoIP system also provides an API (Application Programming Interface) corresponding to a specific database to the shared shared database 21 of the management server 16 so that the shared database 21 of the management server 16 can be accessed. A converter 31 (to be described later) for converting to a corresponding API is provided. By this API conversion, the service of the existing application server 12 can be continued in the IMS.

  In the communication control system 1 configured as described above, the IMS terminal 6 and the VoIP terminal 7 are integrated into the IMS by providing the P-CSCF server 13 with a terminal identification function and a format conversion function. For this reason, it is not necessary to replace the existing VoIP terminal 7 with the IMS terminal 6 when shifting from the existing VoIP system to the IMS. Further, the database of the existing application server 12 is aggregated in the shared database 21 shared by the management server 16 so that the existing application server 12 can access the shared database 21. Thereby, the existing application server 12 can be used as an IMS-compatible application server.

  Hereinafter, with reference to FIG. 2, the P-CSCF server which is the characteristic part of this invention is demonstrated in detail. FIG. 2 is a functional block diagram of the P-CSCF server according to the embodiment of the present invention. In FIG. 2, only the part relating to the terminal identification function and the format conversion function of the P-CSCF server, which is a characteristic part of the present invention, is illustrated.

  As shown in FIG. 2, the P-CSCF server 13 includes a terminal type determination unit 25, a terminal type storage unit 22, and a relay unit 26. When the terminal type determination unit 25 receives a REGISTER message that is session control information for user registration, the terminal type determination unit 25 identifies the terminal type of the transmission source of the REGISTER message and stores it in the terminal type storage unit 22. Specifically, the terminal type determination unit 25 specifies whether the terminal type of the transmission source is the IMS terminal 6 or the VoIP terminal 7 according to the format and message content of the REGISTER message or the reception port. In addition, when the transmission source user terminal is the VoIP terminal 7, the terminal type determination unit 25 may specify the VoIP terminal in more detail as necessary.

  The terminal type storage unit 22 holds terminal type information for each user identifier. The terminal type storage unit 22 holds terminal type information until registration is canceled due to user registration (REGISTER) to deregistration (de-REGISTER), expiration of the registration period, or other reasons. The user identifier is an identifier described in the URI format, and is a public user identifier in the IMS terminal 6, for example. The terminal type information may be information that can identify whether the user terminal is the IMS terminal 6 or the VoIP terminal 7, for example, information indicating whether the user terminal is the IMS terminal 6, or indicates whether the user terminal is the VoIP terminal 7. It may be information.

  The relay unit 26 refers to the terminal type storage unit 22 to identify the terminal type of the transmission / reception destination of the transmission / reception signal, and performs relay processing according to the terminal type. Specifically, the relay unit 26 refers to the terminal type storage unit 22 and identifies the IMS terminal 6 and the VoIP terminal 7 from the user identifier included in the transmission / reception signal. Then, the relay unit 26 relays the VoIP signal format and the IMS signal format with respect to the transmission / reception signal to / from the VoIP terminal 7 stored in the terminal type storage unit 22 by mutually converting the format. On the other hand, the relay unit 26 relays the transmission / reception signal to / from the IMS terminal 6 stored in the terminal type storage unit 22 without performing format conversion.

  Here, with reference to FIG. 3 to FIG. 8, the format conversion processing of the transmission / reception signal by the relay unit of the P-CSCF server will be described with a specific example. 3 to 8 are diagrams showing an example of a format conversion process of transmission / reception signals by the relay unit of the P-CSCF server according to the embodiment of the present invention.

  FIG. 3 shows format conversion by adding authentication information at the time of user registration. At the time of user registration, a REGISTER message is transmitted as a transmission / reception signal from the VoIP terminal 7 to the I-CSCF server 14 via the P-CSCF server 13. At this time, the I-CSCF server 14 requires authentication information (Authorization header) to receive the REGISTER message, but the VoIP terminal 7 does not necessarily attach the authentication information to the REGISTER message. Therefore, the relay unit 26 of the P-CSCF server 13 adds authentication information to the REGISTER message transmitted from the VoIP terminal 7 and relays it to the I-CSCF server 14.

  In this case, the relay unit 26 generates authentication information from the user identifier and the fixed format in the REGISTER message received from the VoIP terminal 7, and adds the generated authentication information to the REGISTER message. Specifically, authentication information such as username and realm of the Authorization header is generated from the value “user1@example.com” of the To header of the REGISTER message. As necessary, the relay unit 26 may generate authentication information using a preset value or a value generated by itself. With this configuration, it is possible to transmit the REGISTER message into the IMS network 2 from the VoIP terminal 7 that does not give the authentication information to the REGISTER message.

  FIG. 4 shows format conversion by adding access network information at the start of a session. At the start of the session, an INVITE message is transmitted as a transmission / reception signal from the VoIP terminal 7 to the S-CSCF server 15 via the P-CSCF server 13. At this time, the S-CSCF server 15 requires the access network information (P-Access-Network header) of the VoIP terminal 7 to receive the INVITE message, but the VoIP terminal 7 does not add the access network information to the INVITE message. . For this reason, the relay unit 26 of the P-CSCF server 13 adds the access network information to the INVITE message transmitted from the VoIP terminal 7 and relays it to the S-CSCF server 15.

  In this case, the relay unit 26 generates access network information from the line type or fixed format of the VoIP terminal 7, and adds the generated access network information to the INVITE message. Also, the relay unit 26 relays the 200 response message transmitted as the response of the INVITE message from the VoIP terminal 7 to the S-CSCF server 15 with the access network information added. With this configuration, it is possible to transmit the INVITE message into the IMS network 2 from the VoIP terminal 7 that does not add the access network information to the INVITE message.

  FIG. 5 shows format conversion by adding routing information at the start of a session. When the user registration is completed, routing information (Service-Route header) is transmitted to the IMS terminal via the P-CSCF server 13 by a REGISTER response (200 response message) from the S-CSCF server 15. This routing information is used in subsequent requests for proper routing in the IMS network 2, but the VoIP terminal 7 cannot recognize the routing information received in the REGISTER 200 response message, and therefore the subsequent INVITE message. Do not add routing information to

  For this reason, the relay unit 26 of the P-CSCF server 13 holds the routing information received from the S-CSCF server 15, adds the routing information to the INVITE message transmitted from the VoIP terminal 7, and sends it to the S-CSCF server 15. Relaying. With this configuration, routing information is given to subsequent requests from the VoIP terminal 7 and routing is appropriately performed in the IMS network 2.

  FIG. 6 shows format conversion of caller information at the start of a session. The caller information is transmitted from the I-CSCF server 14 to the VoIP terminal 7 via the P-CSCF server 13 as an INVITE message. At this time, the I-CSCF server 14 uses the P-Asserted-Identity header as trusted sender information, but the VoIP terminal 7 may not support the P-Asserted-Identity header, and the sender information Will display the contents of the From header to the user.

  For this reason, the relay unit 26 of the P-CSCF server 13 converts the P-Asserted-Identity header in the INVITE message received from the I-CSCF server 14 into a From header that can be understood by the VoIP terminal 7 and sends it to the VoIP terminal 7. Relaying. With this configuration, the VoIP terminal 7 can be notified of caller information.

  FIG. 7 shows the conversion of information about the media at the start of the session. Information about the media is transmitted and received between the user terminals via the P-CSCF server 13 by SDP (Session Description Protocol) set in the body part of the INVITE message (and its 200 response message). The IMS terminal 6 uses media such as video and data in addition to audio media used for the normal VoIP terminal 7. As described above, the VoIP terminal 7 supports a small number of media and has a limited format. Therefore, the relay unit 26 of the P-CSCF server 13 converts the media information.

  In this case, the relay unit 26 converts media information between the IMS terminal 6 and the VoIP terminal 7 based on information set in advance according to the type of terminal to be connected. For example, when the VoIP terminal 7 does not support media codec negotiation and receives INVITE in which a plurality of media codecs are specified from the IMS terminal 6, if media information is relayed to the VoIP terminal 7 as it is, a codec mismatch occurs. An error may occur. Therefore, the relay unit 26 can delete the codec that cannot be used and transmit the codec to the VoIP terminal 7 to establish a connection. Further, when the IMS terminal 6 is a TV phone, it is also possible to convert the media codec information so that only the voice is extracted from the video and the IMS terminal 6 and the VoIP terminal 7 are connected. For example, the relay unit 26 is the H.264 used in the IMS terminal 6. Codec information between a moving image codec such as H.263 and an audio codec such as μ-law used in the VoIP terminal 7 is converted.

  FIG. 8 shows conversion of resource control information at the start of a session. Resource control information is transmitted and received between user terminals via the P-CSCF server 13 in an INVITE message (and its 200 response message). In this case, the IMS terminal 6 has a resource control (QoS: Quality of Service) function, whereas the VoIP terminal 7 does not have a resource control function. Therefore, when resource control is requested in the IMS terminal 6, the IMS terminal 6 and the VoIP terminal 7 cannot be connected. For this reason, the resource control function is terminated at the relay unit 26 of the P-CSCF server 13.

  In this case, the relay unit 26 deletes the resource control information in the INVITE message transmitted from the IMS terminal 6 and relays it to the VoIP terminal 7. Further, the relay unit 26 responds to the resource control information instead of the VoIP terminal 7 from the IMS terminal 6. If the SIP sequence needs to be changed as necessary, the sequence is also converted. With this configuration, the IMS terminal 6 appears to be performing resource control in a pseudo manner, and the IMS terminal 6 and the VoIP terminal 7 can be connected.

  The above-described example is only an example. Format conversion is also performed for the following items. For example, RTP (Real-time Transport Protocol), SRTP (Secure Real-time Transport Protocol), and compatible CODEC. As a SIP sequence, precondition, early media, etc. As network and transport protocols, IPv4 (Internet Protocol Version 4), IPv6 (Internet Protocol Version 6), UDP (User Datagram Protocol), TCP (Transmission Control Protocol), TLS (Transport Layer Security), IPsec (IP Security Protocol) )etc.

  Further, the P-CSCF server 13 has a hardware configuration including a communication interface and a control circuit for realizing each functional block described above. Similarly, the IMS terminal 6, the VoIP terminal 7, the I-CSCF server 14, the S-CSCF server 15, the management server 16, and the application servers 12 and 17 have a hardware configuration including a communication interface and a control circuit. The control circuit is provided with a processor for executing various processes and a memory. The memory is one or a plurality of storage media such as a ROM (Read Only Memory), a RAM (Random Access Memory), and an HDD (Hard Disk Drive), and is configured according to use. Further, various applications such as a control program are stored in the memory.

  Next, user registration processing in the communication control system will be described with reference to FIG. FIG. 9 is a sequence diagram of user registration processing in the communication control system according to the embodiment of the present invention. Here, a case where a VoIP terminal is registered as a user terminal will be described.

  As shown in FIG. 9, the VoIP terminal 7 transmits a REGISTER message including a transmission source IP address, a user identifier, and the like to the P-CSCF server 13 (step S01). The P-CSCF server 13 identifies the terminal type of the transmission source according to the format and message content of the REGISTER message, or the reception port, and stores it in the terminal type storage unit 22 (step S02). At this time, the terminal type storage unit 22 stores the user identifier and terminal identification information indicating the VoIP terminal 7 in association with each other.

  Next, the P-CSCF server 13 converts the REGISTER message received from the VoIP terminal 7 from the VoIP signal format to the IMS signal format (step S03). In this case, addition of authentication information to the REGISTER message is performed as format conversion in the P-CSCF server 13. In addition to the authentication information, access network information is added to the format-converted REGISTER message. Other information is set in accordance with normal IMS regulations.

  Next, the P-CSCF server 13 relays the converted REGISTER message to the I-CSCF server 14 (step S04). The I-CSCF server 14 accesses the management server 16 and selects the S-CSCF server 15 suitable for the VoIP terminal 7 from the list of the S-CSCF server 15 (step S05). Next, the I-CSCF server 14 relays the REGISTER message to the selected S-CSCF server 15 (step S06). The S-CSCF server 15 accesses the management server 16 and performs user authentication (step S07).

  When the user authentication is successful, the S-CSCF server 15 acquires user information from the management server 16 and holds routing information including the address of the P-CSCF server 13 (step S08). This routing information is used for routing from the S-CSCF server 15 to the P-CSCF server 13 when the VoIP terminal 7 is received. Next, the S-CSCF server 15 transmits a 200 response message indicating that user registration has been performed to the P-CSCF server 13 (step S09). At this time, routing information (Service-Route header) including the address of the S-CSCF server 15 is relayed to the P-CSCF server 13 in the 200 response message.

  The P-CSCF server 13 holds routing information including the address of the S-CSCF server 15 received from the S-CSCF server 15 (step S10). This routing information is used for routing from the P-CSCF server 13 to the S-CSCF server 15 when the VoIP terminal 7 originates. Then, the P-CSCF server 13 relays the 200 response message to the VoIP terminal 7 as a signal in response to the INVITE message (step S11).

  Next, session control processing in the communication control system will be described with reference to FIG. FIG. 10 is a sequence diagram of session control processing in the communication control system according to the embodiment of the present invention. Here, a session control process between the VoIP terminal and the IMS terminal will be described. In addition, here, it is assumed that the resource control process is not performed.

As shown in FIG. 10, the VoIP terminal 7 transmits an INVITE message including the user identifier of the sender, the public user identifier of the called party, and the like to the P-CSCF _s server 13a (step S21). The P-CSCF _s server 13a identifies the terminal type of the user terminal based on the user identifier of the transmission source included in the INVITE message and the terminal type storage unit 22 (step S22).

Next, when the P-CSCF _s server 13a identifies the terminal type as the VoIP terminal 7, the P-CSCF _s server 13a converts the INVITE message from the VoIP signal format to the IMS signal format (step S23). In this case, as format conversion in the P-CSCF _s server 13a, addition of access network information to the INVITE message, addition of routing information for the S-CSCF _s server 15a held in the user registration, and the like are performed. Also, conversion of media codec information is performed as necessary.

Next, the P-CSCF _s server 13a relays the INVITE message to the S-CSCF _s server 15a based on the routing information (step S24). The S-CSCF _s server 15a relays the INVITE message to an arbitrary I-CSCF _d server 14 (step S25). The I-CSCF _d server 14 accesses the management server 16 and acquires the address of the S-CSCF _d server 15b based on the public user identifier on the called side (step S26). Next, the I-CSCF _d server 14 relays the INVITE message to the S-CSCF _d server 15b (step S27).

The S-CSCF _d server 15b relays the INVITE message to the P-CSCF _d server 13b based on the routing information for the P-CSCF _d server 13b held at the time of user registration of the terminating IMS terminal 6 (step S28). . The P-CSCF _d server 13b identifies the terminal type of the receiving user terminal based on the destination public user identifier and the terminal type storage unit 22 included in the INVITE message (step S29). Next, when the P-CSCF _d server 13b identifies the terminal type as the IMS terminal 6, the P-CSCF _d server 13b sends the INVITE message to the IMS terminal 6 without converting the format (step S30).

Upon receiving the INVITE message, the IMS terminal 6 on the receiving side calls the receiving side user by using a ring tone or the like (step S31). The calling state of the IMS terminal 6 is notified to the VoIP terminal 7 by a 180 Ringing message. When the terminating IMS terminal 6 responds (step S32), a 200 response message is notified to the VoIP terminal 7 as a response signal of the INVITE message. The 200-response message is also subjected to format conversion in the P-CSCF _s server 13a. Then, an ACK message is returned from the originating VoIP terminal 7 to the terminating IMS terminal 6 to establish a session.

  Next, with reference to FIG. 11, the IMS application of the existing application server will be described. FIG. 11 is an explanatory diagram of the IMS application of the existing application server according to the embodiment of the present invention. In FIG. 11, (a) shows an existing VoIP system, (b) shows a general IMS, and (c) shows a communication control system according to the present invention.

  As shown in FIG. 11A, in the existing VoIP system, the existing application server 12 has a unique database 32 for each application, and an application process and a data input process are performed by an API for the unique database 32. It was done. That is, the existing VoIP system has a different database and API for each application server 12.

  On the other hand, as shown in FIG. 11B, the general IMS has a data input server 18 in addition to the application server 17, and the application process and the data input process are performed by separate servers. In addition, the application server 17 and the data input server 18 access the shared database of the management server 16 and perform processing using the shared database 21. For the access to the shared database 21, an API corresponding to IMS such as Diameter / Sh interface is used.

  Therefore, when the existing application server 12 shown in FIG. 11A is integrated with the IMS shown in FIG. 11B, an API corresponding to IMS is used to access the shared database 21 of the management server 16. It was necessary to change to. Therefore, as shown in FIG. 11C, in the communication control system 1 according to the present embodiment, the application server 12 is provided with a converter 31 that converts an existing non-IMS API into an API compatible with IMS. did. Further, the data input server 18 is made to perform the data input process of the existing application server 12, and the converter 31 is also provided in the data input server 18.

  The converter 31 has an interface on the database side of a general database API and a Diameter / Sh interface. From the viewpoint of the application process and the data input process, the converter 31 appears to operate as a database, and from the registration server 16, the converter 31 appears to be an application server that supports Diameter / Sh. The converter 31 adds, deletes, and changes data of the registration server 16 using Diameter / Sh in accordance with a request for addition, deletion, and change of data entered from the DB-API. Similarly, according to the reference request from the DB-API, the data of the registration server 16 is acquired using Diameter / Sh, and the data is returned to the DB-API as a reference response.

  With this configuration, the existing application server 12 can be referred to the shared database 21 of the management server 16 in the IMS network 2. Therefore, the existing application server 12 can be used as an IMS-compatible application server. In addition, the service of the existing application server 12 can be continued during the transition from the VoIP system to the IMS-compatible communication control system 1.

  Next, a storage system for the shared database of the management server will be described with reference to FIG. FIG. 12 is an explanatory diagram of the shared database storage method of the management server in this embodiment. In FIG. 12, (a) shows an existing VoIP system, (b) shows a general IMS, and (c) shows a communication control system according to the present invention.

  As shown in FIG. 12 (a), in the existing VoIP system, since the existing application server 12 has a unique database, there is no restriction on the data structure, not only information on a user basis, but also users such as companies and systems. It is possible to have information on the group unit to which. That is, it is possible to separately have a table A in which various types of data are associated with each user and a table B in which various types of data are associated with each group.

  The table A includes a user ID field, a data field, and a group ID field, and the table B includes a group ID field and a data field. With this configuration, the tables A and B can be associated with various data via the group IDs stored in the respective group ID fields.

  On the other hand, as shown in FIG. 12B, in general IMS, since the data structure of the shared database 21 of the management server 16 is limited, information can be held only in units of users. Specifically, the shared database 21 includes a user ID field, a data field, and an additional information field called repository data. However, a separate table is provided to hold group information. I can't. Therefore, when the unique database of the existing application server 12 is collected in the shared database 21, it is necessary to store group information as additional information for each user.

  For example, the group information stored in the data field of the table B in FIG. 12A is stored in the additional information field of the shared database 21. With this configuration, it is possible to have group information for each user. However, since the group information held by each user overlaps, the amount of processing such as resource usage and data update increases. In addition, since the data structure of the shared database 21 is significantly different from the database of the existing application server 12, it is necessary to change the processing logic of the application.

  For this reason, as shown in FIG. 12C, the group ID is stored as a dummy user ID in the user ID field of the shared database 21, and information is provided in units of groups. In the additional information field, the user ID and the group information are associated with each other through the group ID by associating the group ID associated with the user ID with the group ID stored in the user ID field.

  With this configuration, the existing database of the application server 12 can be consolidated in the shared database 21 without changing the data structure of the shared database 21. Further, since information is stored while following the database structure of the existing application server 12, it is not necessary to change the processing logic of the application. Furthermore, duplication of group information held by each user can be avoided, and the amount of processing such as lease usage and data update can be reduced.

  As described above, according to the communication control system 1 according to the present embodiment, the transmission / reception signal between the P-CSCF server 13 and the VoIP terminal 7 is relayed after the format conversion. It can be connected to the network 2. This eliminates the need to replace the VoIP terminal 7 with the IMS terminal 6 when shifting from the existing VoIP system to IMS. Therefore, the cost of updating the terminal can be eliminated and the user is not made aware of the equipment change on the network side. In addition, since the VoIP terminal 7 is connected to the IMS, the existing VoIP system equipment can be removed. For this reason, it is possible to shift from the VoIP system to the IMS step by step without coexisting the facilities of the IMS and the VoIP system, and it becomes possible to reduce the capital investment on the network side.

  Next, outgoing / incoming restrictions during an emergency call using the communication control system of the present invention will be described. FIG. 13 is an explanatory diagram of outgoing / incoming call restrictions during an emergency call in the communication control system according to the present embodiment.

  A general call system has a mechanism for preventing disconnection from an emergency caller during an emergency call with a reception terminal. This is realized by reserving an empty line. However, in the case of a call system using IP, a line cannot be reserved because there is no physical path. Therefore, in the communication control system 1 according to the present embodiment, when an emergency call is disconnected from the caller, the call is sent from the other caller to the emergency caller, and the caller is sent to a terminal other than the receiving terminal. And an emergency call application server that reserves the line in a pseudo manner.

  As shown in FIG. 13A, when the user terminal 37 of the emergency call originator sends an emergency call (step S41), the S-CSCF server 15 detects the emergency call number and sends the emergency call to the emergency call application server. Relay to 17a (step S42). The emergency call application server 17a relays the emergency call to the reception terminal 38 and establishes an emergency call (step S43). Further, the emergency call application server 17a adds an iFC (initial Filter Criteria) trigger condition to the shared database 21 of the management server 16 in order to restrict outgoing / incoming calls of emergency callers (step S44).

  When the iFC trigger condition of the management server 16 is changed, the management server 16 notifies the S-CSCF server 15 of the contents (step S45). The iFC trigger condition is set for each user as a user profile of the S-CSCF server 15, and by setting a comparison condition such as a header of a SIP message, a call that matches the condition is specified by a specific application server. It is a condition to relay to. Here, as an iFC trigger condition, a new call from an emergency caller other than an emergency call and an incoming call from an emergency call caller other than an emergency call receiving terminal are regulated (detects a call arrival / departure number to a user). To be transferred to the guidance or server to be disconnected). For example, when the Request-URI of the INVITE message from the emergency call originator is other than the emergency call number or the address of the Contact header of the INVITE message to the emergency call originator is other than from the emergency call application server, the guidance server for disconnecting Alternatively, the iFC transfers the INVITE message to the disconnection application server.

  In this state, when the emergency call originator user terminal 37 is disconnected, the emergency call application server 17a interrupts the disconnection signal, and the call is reserved between the reception terminal 38 and the emergency call application server 17a. When the emergency call application server 17a detects disconnection, the emergency call application server 17a automatically makes an outgoing call to the user terminal 37 of the emergency call originator and tries to reconnect. This is repeated until there is reconnection with the user terminal 37 of the emergency call originator or disconnection from the reception terminal 38 side.

  Further, when a call is made from the user terminal 37 of another caller to the user terminal 37 of the emergency starter, the incoming call is restricted due to the iFC trigger condition of the S-CSCF server 15 and guidance connection or busy disconnection. Furthermore, when a call is made from the user terminal 37 of the emergency call sender to the user terminal 37 of another caller, the incoming call is similarly restricted by guidance connection or busy disconnection. When an emergency call is transmitted from the user terminal 37 of the emergency call originator, the emergency call is relayed again to the emergency call application server 17a and connected to a call with the reception terminal 38 reserved by the emergency call application server 17a. .

  As shown in FIG. 13 (b), when the call is disconnected at the reception terminal 38, the emergency call application server 17a releases the call, and stops when the call is reconnected to the user terminal 37 of the emergency call originator. Then, the emergency call application server 17a deletes the iFC trigger condition from the shared database 21 of the management server 16 (step S47). The management server 16 notifies the S-CSCF server 15 of deletion of the iFC trigger condition, and causes the S-CSCF server 15 to delete the iFC trigger condition (step S48).

  With such a configuration, even in a call system using IP, by providing the emergency call application server 17a, the emergency call sender side during an emergency call between the user terminal 37 of the emergency call sender and the reception terminal 38 can be provided. It is possible to prevent disconnection from. Note that the user terminal 37 in the communication control system 1 described above may be any terminal that can make a call by IP, and may be the VoIP terminal 7 or the IMS terminal 6.

  In the above-described embodiment, the communication control system has a P-CSCF server as a communication control device. However, the present invention is not limited to this configuration. The communication control device may be provided as a part of the P-CSCF server, or may be provided outside if it operates in cooperation with the P-CSCF server.

  In the above embodiment, the IMS terminal and the VoIP terminal are connected to the P-CSCF server. However, the present invention is not limited to this configuration. A P-CSCF server is good also as a structure which connects SIP terminals other than an IMS terminal and a VoIP terminal.

  Further, in the above-described embodiment, the P-CSCF server is configured to connect the VoIP terminal to the IMS, but is not limited to this configuration. The P-CSCF server may be configured to connect the IMS terminal to an existing VoIP system.

  In the embodiment described above, the IMS and the existing VoIP system may coexist. In this case, the P-CSCF is provided with an SBC function. In this case, the IMS terminal may be connected to an existing VoIP system. In this case, the P-CSCF converts the format of the transmission / reception signal from the IMS terminal and relays it.

  The embodiment disclosed this time is illustrative in all respects and is not limited to this embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

  As described above, the present invention has an effect that it is possible to suppress the cost of terminal update and capital investment on the network side by connecting an existing non-IMS terminal to an IMS compatible system. The present invention is useful for a communication control apparatus used for shifting from a system to an IMS and a communication control system including the communication control apparatus.

DESCRIPTION OF SYMBOLS 1 Communication control system 2 IMS network 3 1st access network 4 2nd access network 5 Telephone network 6 IMS terminal 7 VoIP terminal (non-IMS terminal)
11 Soft switch 12 Existing application server 13 P-CSCF server (communication control device)
DESCRIPTION OF SYMBOLS 14 I-CSCF server 15 S-CSCF server 16 Management server 17 Application server 17a Emergency call application server 18 Data input server 21 Shared database 22 Terminal classification memory | storage part 25 Terminal classification determination part 26 Relay part 31 Converter

Claims (10)

A communication control device that performs communication control in an IMS-compatible system for user terminals including IMS terminals and non-IMS terminals,
A terminal type storage unit that holds an IMS terminal or a non-IMS terminal as the terminal type information of the user terminal based on the content of the user registration message from the user terminal or the reception port;
For the transmission / reception signal to / from the non-IMS terminal stored in the terminal type storage unit, the IMS signal format and the non-IMS signal format are reciprocally converted and relayed, and the IMS stored in the terminal type storage unit A communication control apparatus comprising: a relay unit that relays a transmission / reception signal with a terminal without performing the format conversion.   The relay unit further relays the user terminal with a non-IMS compatible system, and when relaying with the non-IMS compatible system, between the non-IMS terminals stored in the terminal type storage unit The transmission / reception signal is relayed without performing the format conversion, and the transmission / reception signal to / from the IMS terminal stored in the terminal type storage unit is relayed after the format conversion. The communication control device according to 1.   The communication control apparatus according to claim 1, wherein the user registration message is a REGISTER message conforming to SIP. The transmission / reception signal is a request message of REGISTER, INVITE, or SUBSCRIBE conforming to SIP,
The relay unit generates authentication information based on a request message received from a non-IMS terminal stored in the terminal type storage unit, and performs format conversion by adding the authentication information to the request message. The communication control apparatus according to any one of claims 1 to 3. The transmission / reception signal is a response message to a REGISTER, INVITE, or SUBSCRIBE request message or INVITE, or SUBSCRIBE request message conforming to SIP,
The relay unit converts the format by adding access network information indicating an access line connected to the non-IMS terminal to a request message or a response message with the non-IMS terminal stored in the terminal type storage unit The communication control device according to any one of claims 1 to 3, wherein The transmission / reception signal is a request message of INVITE or SUBSCRIBE conforming to SIP,
The relay unit holds routing information for the relay device notified from the relay device that performs session control at the time of user registration in the IMS-compatible system, and is received from a non-IMS terminal stored in the terminal type storage unit 4. The communication control device according to claim 1, wherein the format conversion is performed by adding the routing information to the request message. The transmission / reception signal is a request message of INVITE or SUBSCRIBE conforming to SIP,
The relay unit performs format conversion by converting the sender information in the request message for the non-IMS terminal stored in the terminal type storage unit into the sender information that can be processed by the non-IMS terminal. The communication control device according to any one of claims 1 to 3. The transmission / reception signal is an INVITE message conforming to SIP or a response message to the INVITE message,
The relay unit converts information related to media in an INVITE message or response message with the non-IMS terminal stored in the terminal type storage unit into information related to media that can be processed by the non-IMS terminal. The communication control apparatus according to any one of claims 1 to 3, wherein the communication control apparatus is characterized in that: An IMS-compatible management server comprising a communication control device according to any one of claims 1 to 8 and a database connected to the communication control device and having information registered in units of users,
The database of the management server includes a user ID field in which a user ID of the user terminal is registered, and an additional information field in which additional information related to the user terminal is registered,
A user ID is registered in the user ID field, a group ID of a group to which the user terminal belongs is registered as additional information in the additional information field, and a user ID and a group ID are associated, and a group ID is registered in the user ID field. A communication control system comprising: registering, registering group information as additional information in the additional information field, and associating the group ID with the group information, thereby associating the user ID with the group information through the group ID. The IMS-compatible system comprising: the communication control device according to any one of claims 1 to 8; and a management server having a database in which user information of the user terminal relayed from the communication control device is registered. Further comprising the non-IMS application server,
The application server includes a converter that converts an API (Application Programming Interface) for a non-IMS-compliant database into an API for an IMS-compliant database, and the interface conversion by the converter allows the management server's API to be converted via an IMS-compliant API. A communication control system characterized in that an application is provided to the user terminal by referring to a database.

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