JP2012034045A - Communication control method, communication control system, application server and communication control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable notification of a logic number to the receiving side after a logic/physical number conversion, which can be achieved in the traditional line switching telephone network, even in IMS.SOLUTION: The application server, which houses the terminal of a sender that first performs a logical/physical conversion from a logic number to a physical number, attaches a dedicated tag indicating that the physical number conversion has been performed, when an entry is added to the header information section for storing the history of conversions of numbers contained in SIP messages obtained from a sending user's network, before performing the logic/physical conversion. A receiving user's terminal, when receiving an SIP message, searches for the dedicated tag in the SIP message and, if the dedicated tag is detected, determines that a logic/physical number conversion has been performed.

Description

  The present invention relates to a communication control method, a communication control system, an application server, and a communication control program. In particular, in a communication system that performs session control using SIP (Session Initiation Protocol), a destination number (telephone number) specified by a caller The present invention relates to a communication control method, a communication control system, an application server, and a communication control program.

  In a conventional circuit switching network, in an existing circuit switching telephone network as shown in FIG. 4, when a caller dials a destination number (logical number) such as a toll-free number by a telephone, the called user's network ( In the network that accommodates users of logical number conversion, it is converted into a physical number that is the actual destination and connected to the line, and at the same time, the parameters (in the call control signal in the call control signal) Value) and a destination number such as a free dial specified by the caller is notified. As a result, the called party can grasp the advanced service applied from the received logical number.

  In recent years, IMS (Internet protocol Multimedia Subsystem) has been adopted as a method for integrating multimedia services by integrating public communication services such as fixed telephone networks and mobile communication networks with IP (Internet Protocol) technology and SIP used for Internet telephones. Has been introduced.

  In IMS (for example, see Non-Patent Document 1), the SIP protocol is used, but there is no similar parameter in a circuit switching network. Therefore, if the destination logical number / URI (uniform resource identifier) is converted to the physical number / URI in the same case, the request-URI describing the destination URI is rewritten, so notification of the logical number is realized. become unable.

  FIG. 5 shows a system that performs logical / physical number conversion using SIP signals in a conventional IMS. In the figure, a solid line indicates a signal that the SIP signal destination notifies by a logical number, and a thick line indicates that the SIP signal destination is notified by a physical number and information including the logical number (and other) is history-info. This is a signal notified by the header, and the dotted line indicates a non-SIP signal.

  When the SIP signal (logical number) is notified from the originating user's network 1, the incoming (logical) S- is passed through the IBCF (Interconnection Border Control Function) 12 of the network 10 that accommodates the logical number of the called user's network 2. Input to a CSCF (Serving-Call Session Control Function) 13. The S-CSCF 13 is a call state control function for managing a call as a session state. The S-CSCF 13 requests authentication from the destination (logical) HSS (home subscriber server) 11 based on the IP address of the terminal included in the SIP message header, and acquires the authentication result. The S-CSCF 13 transmits a SIP signal (logic) to the application server 14, converts the logical number into a physical number at the application server 14, and passes it to the destination (logical) S-CSCF 13. The destination (logical) S-CSCF 13 transmits a history-info header to the network 20 accommodating the incoming user. The destination (physical) S-CSCF 21 of the network 20 accommodating the incoming user requests authentication from the destination (physical) HSS 22 and obtains an authentication result. Then, the destination P-CSCF (Proxy-Call Session Control Function) 23 stores the history- Send a packet containing the info header. Thereby, the terminal 4 of the called user receives the packet.

  In IMS, when request-URI is converted as described above for various reasons such as a transfer service as shown in FIG. 5, the previous request-URI is stored in the history-info header (for example, see Non-Patent Document 2). ). However, history-info holds all the URIs that are converted for various reasons, so if multiple conversions are performed, it becomes impossible to identify which one was converted for what purpose. As shown in problem a in FIG. 6, since the rewriting history of a large number of SIP URIs is stored, when the number of history-info headers to be stored increases, it becomes difficult to know which one to check. Further, as shown in the problem b in FIG. 6, there is no clear identifier corresponding to the logical number conversion, and thus there is a problem that it is impossible to determine which one should be extracted from a plurality of setting values.

  In order to eliminate the difficulty of identification in the history-info header described above, there is an extension method that enables the tags “mp” and “rc” to be added to each converted entry (for example, Non-Patent Document 3). reference). Specifically, there is a method in which a SIP / SIPS URI Parameter is added to an entry in the history-info header, an mp tag is defined, and a logical number included in the history-info header is identified using the mp tag. However, in the extended specification, consideration is not given to a case where data is transferred to a logical number by transfer from a non-logical number or the like. Therefore, if an entry in the history-info header with the “mp” tag is created before logical number conversion, this method cannot be used. As shown in FIG. 7, if an entry of a history-info header with an “mp” tag is created before another application server performs logical number conversion, a newly established determination as shown in FIG. Processing based on the method cannot be performed.

  In this method, as shown in FIG. 8, each entry of the history-info header (underlined part in FIG. 8) is rewritten every time the related SIP server rewrites the request URI (the destination described in the first line in FIG. 8). Then, add the rewritten value to the back. At that time, the "mp" tag is set when rewriting to another SIP URI from the service viewpoint. Therefore, it can be identified from the entry of the history-info header that the entry described immediately before the entry with the “mp” tag first is a logical number (service number).

(1) 3GPP TS 22.228, (2) TS 23.228, (3) TS 24.228 IETF REC 4244 IETF draft-ietf-sipcore-rfc4244bis-00.

  As described above, in a conventional circuit switching network, a destination number (logical number) such as a free dial number is converted to a high-function node or switch having a number conversion function. A function to notify the callee of the destination number such as a free dial specified by the caller using the parameter (value in the call control signal) included in the call control signal at the time of the call, In order to realize with IP, an IP-based communication network that performs session control by SIP is provided with a header information section (History-info) for recording a history of number conversion in a SIP message and a tag indicating the meaning of the conversion. However, in this SIP method, tags can be assigned unconditionally when number conversion is performed, so the type of number conversion (combination of mutual conversion of logical number and physical number or the number of the actual callee from the number) There is a problem that it is impossible to identify which destination address specified by the caller is first converted to another logical number.

  IMS is expected to be applied to existing circuit-switched telephone networks, and it is important that existing technologies can be used from the viewpoint of maintaining user experience. Therefore, in IMS, it is necessary to equip the same function as the conventional technology in the circuit switching network. Therefore, as shown in FIG. 9, (1) the logical / physical number set by the caller as the destination is set in (1) IMS. Even after the conversion, it is necessary to notify the callee of the logical number, and (2) to establish a function for enabling the callee to recognize the notification.

  The present invention has been made in view of the above points, and is a communication control method capable of realizing in IMS the notification of the logical number after conversion of the logical / physical number that can be realized in a conventional circuit-switched telephone network. It is another object of the present invention to provide a communication control system, an application server, and a communication control program.

In order to solve the above problems, the present invention (Claim 1) is a communication control method for notifying a callee of a number designated by a caller in a communication system for performing session control using SIP. ,
An application server that accommodates the caller's terminal that performs the logical / physical conversion from the logical number to the physical number first.
A dedicated tag indicating that the physical number has been converted when an entry is added to the header information portion that records the history of number conversion in the SIP message obtained from the originating user's network before the logical / physical conversion. And grant
When the terminal of the called user receives the SIP message, the dedicated tag is searched from the SIP message, and if there is the dedicated tag, it is determined that the logical / physical number conversion has been performed.

Further, the present invention (Claim 2) accommodates a terminal of a caller that first performs logical / physical conversion from a logical number to a physical number in a system that performs session control using SIP, and is designated by the caller. A communication control system for notifying a called party of a number,
A network application server that houses the logical number;
An incoming user terminal connected to the network accommodating the incoming user,
The application server is
Logical / physical number conversion means for converting the logical number of the SIP message acquired from the calling user's network into a physical number;
A dedicated tag indicating that the physical number has been converted when an entry is added to the header information portion that records the history of number conversion in the SIP message obtained from the originating user's network before the logical / physical conversion. Means for providing
Have
The incoming user terminal is:
When the SIP message is received, the dedicated tag is searched from the SIP message, and when there is the dedicated tag, there is means for determining that the logical / physical number conversion has been performed.

In addition, the present invention (Claim 3) is a communication system that performs session control using SIP, and accommodates a sender's terminal that performs logical / physical conversion from a logical number to a physical number first, and the sender designates An application server for notifying the called party of the number
Logical / physical number conversion means for converting the logical number of the SIP message acquired from the calling user's network into a physical number;
A dedicated tag indicating that the physical number has been converted when an entry is added to the header information portion that records the history of number conversion in the SIP message obtained from the originating user's network before the logical / physical conversion. Means for providing
Have

  Moreover, this invention (Claim 4) is a communication control program for functioning a computer as each means which comprises the application server of Claim 3.

  As described above, the present invention maintains the architecture specifications and protocol specifications of the prior art, and the application server enters an entry in the header information portion that records the history of number conversion in the SIP message before performing logical / physical conversion. When adding a special tag, it is possible for the callee side to recognize that physical number conversion has been performed when there is a dedicated tag in the received header information part.

  Thereby, this invention has the following effects.

  -There is no need to link the other device with the other device without changing the IMS architecture.

  In addition to the above, it is possible to reliably determine the history of logical number conversion that cannot guarantee completeness.

  As described above, the notification to the called party of the logical number after the logical number conversion, which can be realized in the conventional circuit-switched telephone network, can also be realized in the IMS.

1 is a system configuration diagram according to an embodiment of the present invention. It is a block diagram of the application server in one embodiment of this invention. It is an image of a dedicated tag given by the application server in one embodiment of the present invention. It is an example of circuit switching in a conventional telephone network. It is a system block diagram which performs the conversion of the logical / physical number by the SIP signal in the conventional IMS. This is a description example of the history-info header. It is a system configuration | structure figure of the expansion system of the prior art in IMS. It is a figure which shows the expansion system of the prior art in IMS. It is a figure for demonstrating a subject.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a system configuration according to an embodiment of the present invention. In this figure, the same components as those in FIG. The system configuration is the same as that in FIG. 5, but the function of the application server 100 is different. The meanings indicated by the bold lines and dotted lines shown in the figure are the same as in FIG.

  As illustrated in FIG. 2, the application server 100 includes a transmission / reception interface (I / F) 110, an information addition unit 120, and a conversion unit 140.

  When the application server 100 receives a packet via the transmission / reception I / F 110, the information adding unit 120 adds information indicating what service is converted to the tag to be recorded in the history-info, and then the logical value is converted by the conversion unit 140. The number is converted into a physical number and sent to the destination logical S-CSCF 13 via the transmission / reception I / F 110.

  The destination user terminal 4 has a function of receiving a SIP signal including a history-info header, searching for an entry with a dedicated tag, and determining whether a dedicated tag has been assigned. The function enables the called-side user terminal 4 to identify the logical number initially specified by the caller by extracting the first conversion tag related to the service from the tag type.

  The operation of the components of the application server shown in FIG. 2 can be constructed as a program, installed in a computer used as the application server and executed, or distributed via a network.

  Further, the constructed program can be stored in a portable storage medium such as a hard disk, a flexible disk, or a CD-ROM, and can be installed or distributed on a computer.

  The present invention is not limited to the above-described embodiment, and various modifications and applications can be made within the scope of the claims.

1 Calling user's network 2 Calling user's network 3 Calling terminal 4 Calling terminal 10 Network 11 containing the logical number Called (logical) HSS
12 IBCF
13 arrival (logic) S-CSCF
14 Application server 20 Network 21 that accommodates incoming users Arrived (physical) S-CSCF
22 arrival (physical) HSS
23 P-CSCF
DESCRIPTION OF SYMBOLS 100 Application server 110 Transmission / reception interface 120 Information provision part 140 Conversion part

Claims (4)

In a communication system that performs session control using SIP (Session Initiation Protocol), a communication control method for notifying a callee of a number designated by a caller,
An application server that accommodates the caller's terminal that performs the logical / physical conversion from the logical number to the physical number first.
A dedicated tag indicating that the physical number has been converted when an entry is added to the header information portion that records the history of number conversion in the SIP message obtained from the originating user's network before the logical / physical conversion. And grant
When the terminal of the called user receives the SIP message, the dedicated tag is searched from the SIP message, and when there is the dedicated tag, it is determined that logical / physical number conversion has been performed. Communication control method. In a system that performs session control using SIP (Session Initiation Protocol), it accommodates the caller's terminal that first performs logical / physical conversion from a logical number to a physical number, and notifies the caller of the number specified by the caller A communication control system for
A network application server that houses the logical number;
An incoming user terminal connected to the network accommodating the incoming user,
The application server is
Logical / physical number conversion means for converting the logical number of the SIP message acquired from the calling user's network into a physical number;
A dedicated tag indicating that the physical number has been converted when an entry is added to the header information portion that records the history of number conversion in the SIP message obtained from the originating user's network before the logical / physical conversion. Means for providing
Have
The incoming user terminal is:
Communication having a means for searching for the dedicated tag from the SIP message upon receiving the SIP message and determining that logical / physical number conversion has been performed when the dedicated tag is present Control system. A communication system that performs session control using SIP (Session Initiation Protocol). It accommodates the caller's terminal that performs the first logical / physical conversion from a logical number to a physical number. An application server for notification,
Logical / physical number conversion means for converting the logical number of the SIP message acquired from the calling user's network into a physical number;
A dedicated tag indicating that the physical number has been converted when an entry is added to the header information portion that records the history of number conversion in the SIP message obtained from the originating user's network before the logical / physical conversion. Means for providing
An application server comprising:   The communication control program for functioning a computer as each means which comprises the application server of Claim 3.

Images