JP5873396B2 - Mobile communication system, location registration method - Google Patents

Description

  The present invention relates to a mobile communication system and a location registration method, and more particularly, to a mobile communication system and a location registration method for performing combined location registration.

  According to TS23.007 of 3GPP, which is a standard for mobile communication, if a failure or resumption of operation occurs in HLR (Home Location Register) or HSS (Home Subscriber Server), the HLR / HSS is profiled by itself. Reset to each VLR (Visit Location Registration Register), SGSN (Serving General Packet Radio Service Support Node) or MME (Mobility Management Entity) message, which is reset to the MLR (Mobility Management Entity) message. (For example, Non-Patent Document 1).

  Each VLR / SGSN / MME that has received this reset message is “Location Information Configured in HLR” (hereinafter abbreviated as LICH), which is one of the flags of the profile information of the subscribers accommodated in the corresponding HLR / HSS. Is set to “Not Confirmed”. This LICH flag is used to prompt the relocation registration accommodated in the HLR in order to eliminate the location information mismatch that may occur due to the backup timing of the profile information of the subscriber when the HLR preliminary switching occurs. This is a flag added to the profile information of the subscriber. The SGSN always performs Update Location (location registration) on the HLR / HSS, triggered by the incoming and outgoing calls and location registration (periodic location registration) of the subscriber terminal whose LICH is set to “Not Confirmed”. , Update the state of the HLR. By doing so, it is possible to achieve matching between the information held in the SGSN and the information held in the HLR.

  Normally, when outgoing / incoming calls or periodic location registration is performed, location registration is not performed for the HLR. However, as described above, for subscriber terminals whose LICH is set to “Not Confirmed” The location registration process is always performed for the HLR. As described above, even when the location is not changed, the location registration for the HLR needs to be performed, in addition to the case where the LICH is “Not Confirmed”, the SDCH (Subscriber Data Confirmed by HLR) is “ It may be “Not Confirmed”.

"3GPP Specification detail", 3GPP, [Search May 1, 2012], Internet <URL: http://www.3gpp.org/ftp/Specs/html-info/23007.htm>

  By the way, according to the 3GPP standard, when a serving node (SGSN, VLR) is changed, a network area (CS area) for processing a circuit switching (CS) call, a packet switching (PS: Packet) A location registration signal is to be transmitted for each of the network areas (PS areas) for processing (Switching) calls. If similar signals are transmitted twice, network resources may not be effectively used. To solve this problem, a CS call (hereinafter simply referred to as CS), a PS call ( Hereinafter, a specification for transmitting a combined (COMBINED) location registration signal (hereinafter referred to as a COMBINED location registration signal), which is a location registration signal for performing location registration collectively, may be considered. In that case, according to the standard function of 3GPP, after receiving the COMBINED location registration signal from the mobile terminal by the SGSN, location registration is performed for the HLR by CS / PS single location registration. In the following description, the case of HLR will be described, but the same description is valid for HSS.

  FIG. 16 shows a case where a location registration signal is independently transmitted for each of the CS call and the PS call. Referring to FIG. 16, there are PS areas PSA1 and PSA2 corresponding to the two SGSNs 11 and SGSN12, respectively. In addition, CS areas CSA1 and CSA2 exist corresponding to the two VLRs 21 and 22 respectively. Consider a case where the mobile terminal MT moves as indicated by an arrow Y in such an area configuration. In the PS area PSA2 and CS area CSA2 after movement, the mobile terminal MT performs an attach process or a location registration process. For example, when the mobile terminal MT transmits a location registration signal as indicated by an arrow Y1, a location registration signal related to the CS call is transmitted to the HLR 10 via a route indicated by arrows Y2 and Y3, and a location registration signal related to a PS call is indicated via the route indicated by arrow Y4. It is transmitted to the HLR 10.

  FIG. 17 shows a case where a COMBINED location registration signal is transmitted for a CS call and a PS call. Referring to FIG. 17, the area configuration is the same as in FIG. Consider a case where the mobile terminal MT moves as indicated by an arrow Y. In the PS area PSA2 and CS area CSA2 after movement, the mobile terminal MT performs an attach process or a location registration process. For example, when the mobile terminal MT transmits a location registration signal as indicated by the arrow Y1, the COMBINED location registration signal is transmitted to the HLR 10 along the paths indicated by the arrows Y2 and Y3.

  FIG. 18 shows a case where only the SGSN is changed (the VLR is not changed). Referring to FIG. 18, there are PS areas PSA1 and PSA2 corresponding to the two SGSNs 11 and SGSN12, respectively. A CS area CSA exists corresponding to the VLR 21. Consider a case where the mobile terminal MT moves as indicated by an arrow Y in such an area configuration. In the PS area PSA2 after movement, the mobile terminal MT performs an attach process or a location registration process. For example, when the mobile terminal MT transmits a location registration signal as indicated by the arrow Y1, a location registration signal related to the PS call is transmitted to the HLR 10 via the route indicated by the arrow Y4.

  FIG. 19 shows a case where only the VLR is changed (the SGSN is not changed). Referring to FIG. 19, there is a PS area PSA corresponding to the SGSN 11. In addition, CS areas CSA1 and CSA2 exist corresponding to the two VLRs 21 and 22 respectively. Consider a case where the mobile terminal MT moves as indicated by an arrow Y in such an area configuration. In the CS area CSA2 after movement, the mobile terminal MT performs an attach process or a location registration process. For example, when the mobile terminal MT transmits a location registration signal as indicated by an arrow Y1, a location registration signal related to a CS call is transmitted to the HLR 10 via the paths indicated by arrows Y2 and Y3.

When the above-described COMBINED location registration signal is employed, for example, the number of location registration signals can be reduced by performing the following function expansions (1) to (3).
(1) When the mobile terminal moves and both SGSN and VLR are changed, a COMBINED location registration signal is transmitted.
(2) When the mobile terminal moves and only the SGSN is changed (when there is no change in the VLR), a PS single location registration signal is transmitted.
(3) When the mobile terminal moves and only the VLR is changed (when there is no change in the SGSN), a CS single location registration signal is transmitted.

In the above case, a different signal is transmitted to the HLR when the SGSN does not change (Intra-SGSN) and when the SGSN changes (Inter-SGSN).
(A) When SGSN does not change (Intra-SGSN)
In this case, during normal times, a LOCATION UPDATE REQUEST is transmitted from the SGSN to the VLR according to the 3GPP standard BSSAP + (Base Station System Application Part +) protocol, and a MAP_UPDATE LOCATION REQUEST is transmitted from the VLR to the HLR.

  On the other hand, when forcibly performing location registration, two signals are transmitted. That is, a LOCATION UPDATE REQUEST according to the BSSAP + protocol is transmitted from the SGSN to the VLR, and a MAP_UPDATE LOCATION REQUEST is transmitted from the VLR to the HLR. Further, MAP_UPDATE GPRS LOCATION REQUEST is transmitted from the SGSN to the HLR.

(B) When SGSN changes (Inter-SGSN)
When following the standard function of 3GPP, two signals are transmitted. A LOCATION UPDATE REQUEST according to the 3SAPP standard BSSAP + protocol is transmitted from the SGSN to the VLR, and a MAP_UPDATE LOCATION REQUEST is transmitted from the VLR to the HLR. Further, MAP_UPDATE GPRS LOCATION REQUEST is transmitted from the SGSN to the HLR.
On the other hand, when transmitting a COMBINED location registration signal, the COMBINED LOCATION is an extension of the 3GPP standard BSSAP + protocol from SGSN to SIN.

UPDATE REQUEST is transmitted, and COMBINED UPDATE LOCATION REQUEST, which is an extension of MAP, is transmitted from the VLR to the HLR.
As described above, although the SGSN does not change, if it is desired to perform location registration forcibly, it is necessary to send two signals, so the load on the HLR increases. Therefore, it is considered effective to use the COMBINED location registration signal. However, since the COMBINED location registration signal is based on the Inter-SGSN, there is a concern that if the COMBINED location registration signal is used in the Intra-SGSN, the location profile information is canceled (deleted).

(CS single position registration signal and COMBINED position registration signal)
Next, a case where a single location registration signal is transmitted for each of a CS call and a PS call and a case where a COMBINED location registration signal is transmitted will be described.
First, with reference to FIG. 20, a case where a single location registration signal is transmitted for each of the CS call and the PS call instead of the COMBINED location registration signal will be described.

  FIG. 20 is a diagram illustrating a configuration example of a network from the SGSN 11 to the HLR 10, and is based on the IMS network configuration. In the example of FIG. 20, CS-GW (Circuit Switching-Gateway) 13 a and 13 b, I / S-CSCF (Interrogating / Serving-Call Session Control Function) 14, AS (Application Serving) 11 to L (SG 10), L to SG SG 11, L to SG SG Up to the network is configured.

  In FIG. 20, the LICH flag is set in the SGSN 11 when an HLR failure or an operation restart occurs. When the mobile terminal MT outputs a location registration signal when the LICH flag is set, the SGSN 11 transmits a location registration signal independently for each of the CS call and PS call (S141). At this time, since the CS-GW 13a cannot be selected due to a line failure or the like, another CS-GW 13b is selected (S142). When the CS-GW 13b receives the CS single location registration signal from the SGSN, the CS-GW 13b notifies the HLR 10 of the CS single location registration signal (S143).

The HLR 10 performs the following processing (S144). When the HLR 10 receives the PS single location registration signal, the HLR 10 checks the SGSN 11 located in the HLR 10 and therefore does not instruct the SGSN 11 to delete the profile information (S144). When the HLR 10 receives the CS single location registration signal, the HLR 10 checks the CS-GW located in the HLR 10 and instructs the CS-GW 13b to delete the profile information (S144).
As described above, no problem arises when a single location registration signal is transmitted for each of the CS call and PS call.

Next, with reference to FIG. 21, a case where a COMBINED location registration signal is used will be described.
In the example of FIG. 21 as well, the network from the SGSN 11 to the HLR 10 is configured by the CS-GWs 13a and 13b, the I / S-CSCF 14, and the AS 15 as in the case of FIG.

In FIG. 21, the LICH flag is set in the SGSN 11 when an HLR failure or an operation restart occurs. When the mobile terminal MT outputs a location registration signal when the LICH flag is set, the SGSN 11 transmits a COMBINED location registration signal in order to perform COMBINED location registration (S151). At this time, since the CS-GW 13a cannot be selected due to a line failure or the like, another CS-GW 13b is selected (S152). When the CS-GW 13b receives the COMBINED location registration signal from the SGSN, the CS-GW 13b notifies the HLR 10 of the COMBINED location registration signal (S153).
The HLR 10 performs the following processing (S154). When receiving the COMBINED location registration, the HLR 10 recognizes that both SGSN and CS-GW have changed, and instructs both SGSN and CS-GW to delete profile information.

In this figure, erasure of profile information is instructed by the HLR 10, but there is also a format that is determined by the AS15. Even in that case, both SGSN and CS-GW are instructed to delete profile information, and the same problem occurs.
As a result, the profile information stored in the SGSN is deleted, and location registration for the mobile terminal MT cannot be performed (S155).
Therefore, when a single location registration signal for CS and PS calls is replaced with a COMBINED location registration signal as it is, the profile information stored in the SGSN currently in the service area is deleted and location registration cannot be performed.

(Problems when using COMBINED location registration signal)
A detailed operation example when the COMBINED position registration signal is used will be described with reference to FIG.
FIG. 22 is a diagram illustrating an example of a network configured by SGSNs 11a and 11b, CS-GWs 13a and 13b, I / S-CSCFs 14a and 14b, AS 15a and 15b, and HLR 10. The SGSN 11a holds information regarding the node number of the CS-GW to be connected and the Gs-Ass (Gs-Association) state (a state where the SGSN and the MSC are linked). Further, the CS-GW 13a and the CS-GW 13b respectively hold information on the AS node number, the I / S-CSCF node number, the SGSN node number, and the Gs-Ass state of the connection destination. The AS 15a holds the node number of the CS-GW that is the connection destination.

  In FIG. 22, when the mobile terminal MT performs COMBINED attach (S161) and outputs a location registration signal, the SGSN 11 transmits BSSAP + COMBINED LOCATION UPDATE REQUEST to the CS-GW 13b to perform COMBINED location registration (S162). When receiving the COMBINED location registration, the CS-GW 13b recognizes the Inter-SGSN and sets the Inter-SGSN in the SIP REGISTER (S163). The SIP REGISTER (Inter-SGSN / Inter-CS-GW) transmitted by the CS-GW 13b is sent to the AS 15a via the I / S-CSCF 14b (S164, S165). The AS 15a that has received this SIP REGISTER (Inter-SGSN / Inter-CS-GW) transmits a MAP COMMITTED UPDATE LOCATION REQUEST to the HLR 10 (S166). The HLR 10 does not transmit MAP_Cancel Location (hereinafter also referred to as CL) (S167).

By the way, since the AS 15a is notified of “Inter-SGSN” from the I / S-CSCF, the AS 15a recognizes that it is straddling the SGSN, sets “UMSC” in the MAP_CL, and transmits it to the CS-GW (S168). ). When “UMSC” is set in MAP_CL, the profile information held in both “VLR” and “SGSN” is to be deleted. The AS 15a transmits SIP Notify and MAP_CL (S169a, S169b).
The CS-GW 13a that has received the MAP_CL receives the cancel signal with the “UMSC” designation from the AS 15a, and transmits the cancel signal to the SGSN 11a (S170). The CS-GW 13a transmits MAP_CL (S171). When the SGSN 11a receives the cancel signal, the SGSN 11a deletes the stored profile information (S172).

As described above, there is no problem with the COMBINED location registration transmitted when the SGSN is changed. However, even if the SGSN does not change, the COMBINED location registration may be transmitted, and when this is received by the AS, it is stored in the old SGSN (actually, the SGSN corresponding to the area currently located because it has not moved). This is a problem because an instruction to delete the profile information is issued.
The same problem occurs in the case of a network provided with a general SGSN and VLR.

This problem will be described with reference to FIGS.
First, with reference to FIG. 23, a case will be described in which a single location registration signal is transmitted for each of the CS call and PS call instead of the COMBINED location registration signal.
In the example of FIG. 23, VLRs 21 and 22 are provided in the network from the SGSN 11 to the HLR 10.

  In FIG. 23, the LICH flag is set in the SGSN 11 when an HLR failure or an operation restart occurs. If the mobile terminal MT outputs a location registration signal when the LICH flag is set, the SGSN 11 transmits a location registration signal independently for each of the CS call and PS call (S141a). At this time, since the VLR 21 cannot be selected due to a line failure or the like, another VLR 22 is selected (S142a). When the CS-GW 13b receives the CS single location registration signal from the SGSN, the CS-GW 13b notifies the HLR 10 of the CS single location registration signal (S143a).

The HLR 10 performs the following processing (S144a). When the HLR 10 receives the PS single location registration signal, the HLR 10 checks the SGSN 11 located in the HLR 10 and therefore does not instruct the SGSN 11 to delete the profile information (S144a). When the HLR 10 receives the CS single location registration signal, the HLR 10 checks the VLR located in the HLR 10 and instructs the VLR to delete the profile information (S144a).
As described above, no problem arises when a single location registration signal is transmitted for each of the CS call and PS call.

Next, with reference to FIG. 24, a case where a COMBINED location registration signal is used will be described.
Also in the example of FIG. 24, VLRs 21 and 22 are provided in the network from the SGSN 11 to the HLR 10 as in the case of FIG.
In FIG. 24, the LICH flag is set in the SGSN 11 when an HLR failure or an operation restart occurs. When the mobile terminal MT outputs a location registration signal when the LICH flag is set, the SGSN 11 transmits a COMBINED location registration signal to perform COMBINED location registration (S151a). At this time, since the VLR 21 cannot be selected due to a line failure or the like, another VLR 22 is selected (S152a). When receiving the COMBINED location registration signal from the SGSN, the VLR 22 notifies the HLR 10 of the COMBINED location registration signal (S153a).

The HLR 10 performs the following processing (S154a). When the HLR 10 receives the COMBINED location registration, the HLR 10 recognizes that both the SGSN and the VLR have changed, and instructs the SGSN and the VLR to delete profile information.
As a result, the profile information stored in the SGSN is deleted, and location registration for the mobile terminal MT cannot be performed (S155a).
Therefore, when a single location registration signal for CS and PS calls is replaced with a COMBINED location registration signal as it is, the profile information stored in the SGSN currently in the service area is deleted and location registration cannot be performed.

  FIG. 25 is a diagram illustrating an example of a network configured by the SGSNs 11a and 11b, the VLRs 21 and 22, and the HLR 10. The SGSN 11a holds information on the node number of the connection-target VLR and the Gs-Ass state. Moreover, VLR21 and 22 hold | maintain the information regarding the node number of SGSN of a connection destination, and the state of Gs-Ass, respectively.

  In FIG. 25, when the mobile terminal MT performs COMBINED attach (S161a) and outputs a location registration signal, the SGSN 11 transmits BSSAP + COMBINED LOCATION UPDATE REQUEST to the VLR 22 in order to perform COMBINED location registration (S162a). When receiving the COMBINED location registration, the VLR 22 recognizes the Inter-SGSN (S163a). Then, the VLR 22 transmits a MAP COMMITTED UPDATE LOCATION REQUEST to the HLR 10 (S166a).

  Since the HLR 10 is notified of the COMBINED location registration from the VLR 22 corresponding to the newly located area, the HLR 10 recognizes that both the SGSN and VLR have changed, and MAP_Cancel Location (hereinafter referred to as CL) for the VLR 21 corresponding to the former located area. "UMSC" is set in (sometimes) (S168a) and transmitted to the VLR 21 (S169b). If “UMSC” is set in MAP_CL, the profile information held in both “VLR” and “SGSN” will be deleted.

The VLR 21 that has received the MAP_CL receives the cancel signal with the designation “UMSC”, and therefore transmits the cancel signal to the SGSN 11a (S170a). That is, the VLR 21 transmits a cancel signal MAP_CL to the SGSN 11a (S171a). When the SGSN 11a receives the cancel signal MAP_CL, the SGSN 11a deletes the held profile information (S172a).
As described above, there is no problem with the COMBINED location registration transmitted when the SGSN is changed. However, even if the SGSN does not change, the COMBINED location registration may be transmitted, and when this is received by the HLR, it is stored in the old SGSN (actually, the SGSN corresponding to the area currently located because it has not moved). This is a problem because an instruction to delete the profile information is issued.

As described above, there is a case where the SGSN has not changed (Intra-SGSN) and still wants to perform location registration, such as LICH = Not Confirmed. In such a case, if CS / PS single location registration is performed, two location registration signals are transmitted, and the number of location registration signals addressed to the HLR increases. In order to reduce the number of location registration signals addressed to the HLR, there is a problem because the existing technology deletes the profile information of the in-service SGSN in the case of Intra-SGSN even when trying to use COMBINDE location registration. I can't.
The present invention has been made to solve the above-described problems of the prior art, and the purpose thereof is a mobile communication system that can use a COMBINED location registration signal without any problem even in the case of Intra-SGSN. It is to provide a location registration method.

  A mobile communication system according to an aspect of the present invention relates to a mobile terminal addressed to an exchange corresponding to an old area where the mobile terminal is located when a location registration signal related to the mobile terminal is received. A first apparatus that transmits a deletion instruction signal including an instruction to delete subscriber profile information, and a position registration signal that should be transmitted even when the area where the mobile terminal is located has not been changed. And a second device that transmits to the first device, including transmission suppression information for suppressing transmission of the deletion instruction signal. According to such a configuration, the COMBINED location registration signal can be used even in the case of Intra-SGSN.

The location registration signal may be a COMBINED location registration signal for collectively performing location registration processing relating to line connection and location registration processing relating to packet connection. According to such a configuration, since the COMBINED location registration signal can be used even in the forced location registration when the SGSN has not changed, the signal is compared with the case where the CS / PS single location registration signal is used. Since the number can be reduced, the load on the HLR can be reduced.
Further, the location registration signal to be transmitted even when the area where the mobile terminal is located has not been changed is when the “Location Information Configured in HLR” of the subscriber profile information is set to “Not Confirmed”. It may be a location registration signal to be transmitted.

  Note that the location registration signal to be transmitted even when the area where the mobile terminal is located has not been changed, the location registration signal transmitted when the subscriber profile information held in the exchange may not be accurate. It may be a signal. When the location registration of a mobile terminal is forcibly performed, such as when the accuracy of subscriber profile information held by the SGSN is not confident, even when the SGSN has not changed, the COMBINED location registration is performed. By not giving an instruction to delete the subscriber profile information held in the SGSN, it is possible to prevent troubles in communication using the mobile terminal.

  A location registration method according to an aspect of the present invention relates to a mobile terminal addressed to an exchange corresponding to an old area where the mobile terminal was located when a location registration signal related to the mobile terminal is received. The first step in which the first device transmits a deletion instruction signal including an instruction to delete subscriber profile information, and the position registration signal to be transmitted even when the mobile terminal's coverage area has not been changed, And a second step in which the second device transmits to the first device, including transmission suppression information for suppressing transmission of the deletion instruction signal by the first device. Yes. By this method, even in the case of Intra-SGSN, the COMBINED location registration signal can be used without causing a problem.

  According to the present invention, by adding a parameter and functioning as a flag indicating that the parameter should not be deleted and a flag indicating that the deletion is prohibited, the COMBINED location registration signal can be generated without causing a problem even in the case of LICH = Not Confirmed, for example. Can be used.

It is a block diagram which shows the structural example of the mobile communication system by embodiment of this invention. It is a figure which shows the structure corresponding to the 1st plan in the case of implement | achieving the mobile communication system by embodiment of this invention. It is a figure which shows the structure corresponding to the 2nd plan in the case of implement | achieving the mobile communication system by embodiment of this invention. It is a flowchart which shows the operation example of the mobile communication system at the time of employ | adopting a 1st plan. It is a flowchart which shows the operation example of the mobile communication system at the time of employ | adopting a 2nd plan. In the 1st plan, it is a sequence figure showing signal exchange in the case of Intra-SGSN, Inter-CS-GW, and no AS straddling. In 1st plan, it is a sequence diagram which shows signal transmission in the case of Intra-SGSN, Inter-CS-GW, and AS straddling. In the 2nd plan, it is a sequence figure showing signal exchange in the case of Intra-SGSN, Inter-CS-GW, and no AS straddling. It is a sequence diagram which shows signal transmission in the case of Intra-SGSN, Inter-CS-GW, and AS straddling in 2nd plan. It is a figure which shows the structure of the modification 1 of the mobile communication system by embodiment of this invention, and is a figure which shows the structural example in the case of including HLR and VLR. 11 is a flowchart showing an operation example of a mobile communication system adopting the configuration of FIG. 10. It is a sequence diagram which shows signal transmission / reception of the mobile communication system which employ | adopted the structure of FIG. It is a figure which shows the structure of the modification 2 of the mobile communication system by embodiment of this invention, and is a figure which shows the structural example in the case of including HLR and VLR. It is a flowchart which shows the operation example of the mobile communication system which employ | adopted the structure of FIG. It is a sequence diagram which shows signal transmission / reception of the mobile communication system which employ | adopted the structure of FIG. It is a figure which shows the case where a location registration signal is each transmitted independently regarding CS call and PS call. It is a figure which shows the case where a COMBINED position registration signal is transmitted regarding CS call and PS call. It is a figure which shows the case where only SGSN changes. It is a figure which shows the case where only VLR has a change. It is a figure which shows the case where not a COMBINED location registration signal but a single location registration signal is transmitted about CS call and PS call, respectively. It is a figure which shows the case where a COMBINED position registration signal is used. It is a figure which shows the detailed operation example in the case of using a COMBINED position registration signal. It is a figure which shows the other example in the case of transmitting each independent position registration signal about CS call and PS call instead of a COMBINED position registration signal. It is a figure which shows the other example in the case of using a COMBINED position registration signal. It is a figure which shows the other example of a detailed operation example in the case of using a COMBINED position registration signal.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings referred to in the following description, the same parts as those in the other drawings are denoted by the same reference numerals.
(Configuration example of mobile communication system)
FIG. 1 is a block diagram showing a configuration example of a mobile communication system according to an embodiment of the present invention. Referring to the figure, the mobile communication system according to the present embodiment includes a first device 1, a second device, and an exchange 3.
When the first apparatus 1 receives a location registration signal related to the mobile terminal MT, the first device 1 sends a subscriber related to the mobile terminal MT to the exchange 3 corresponding to the old area where the mobile terminal MT was located. It has a function of transmitting a deletion instruction signal including an instruction to delete profile information.

Further, the second device transmits transmission suppression information for suppressing transmission of a deletion instruction signal by the first device 1 to a position registration signal to be transmitted even when the area where the mobile terminal MT is not changed. Including the function of transmitting to the first device 1.
By providing such a configuration in the mobile communication system, for example, even when LICH = Not Confirmed, the COMBINED location registration signal can be used without causing a problem.
Hereinafter, the mobile communication system according to the present embodiment will be described more specifically.

(Outline of mobile communication system)
In order to solve the above-described problem, in this embodiment, a parameter indicating whether it is Inter-SGSN or Intra-SGSN is added to a signal for forcibly performing location registration. By adding this parameter, it is possible to identify whether it is an Inter-SGSN or an Intra-SGSN. Therefore, even if a COMBINED location registration signal is used, location registration processing can be performed without any problem. It becomes like this. More specifically, it is as follows.

(A) When SGSN does not change (Intra-SGSN)
In this case, in normal time, a LOCATION UPDATE REQUEST by BSSAP + protocol is transmitted from the SGSN to the CS-GW, and a MAP_UPDATE LOCATION REQUEST is transmitted from the CS-GW to the HLR.
On the other hand, in the case of forcibly performing location registration, a COMBINED LOCATION UPDATE REQUEST that is an extension of the BSSAP + protocol is transmitted from the SGSN to the CS-GW. A parameter “Intra-SGSN” is added to this COMBINED LOCATION UPDATE REQUEST. Also, MAP_COMBINED UPDATE LOCATION REQUEST is transmitted from the CS-GW to the HLR. By adding parameters in this way, the COMBINED location registration signal can be used even in Intra-SGSN, in which there is no change in SGSN.

(B) When SGSN changes (Inter-SGSN)
When following the standard function of 3GPP, two signals are transmitted. A LOCATION UPDATE REQUEST according to the 3SAPP standard BSSAP + protocol is transmitted from the SGSN to the CS-GW, and a MAP_UPDATE LOCATION REQUEST is transmitted from the CS-GW to the HLR. Further, MAP_UPDATE GPRS LOCATION REQUEST is transmitted from the SGSN to the HLR.
On the other hand, when transmitting the COMBINED location registration signal, the COMSNED LOCATION UPDATE REQUEST that is an extension of the 3SAPP standard BSSAP + protocol is transmitted from the SGSN to the CS-GW, and the MAP_COMBINED UPDATE LOCATION REQUEST is transmitted from the CS-GW to the HLR.

(COMBINED position registration signal)
Here, for the COMBINED location registration signal, for example, the following two proposals can be considered.
The first plan is as follows. That is, for the signal from SGSN to CS-GW, a parameter indicating “Intra-SGSN” is added to the COMBINED location registration signal. In addition, for the signal from the CS-GW to the AS via the I / S-CSCF, the SIP signal is used to indicate “Intra-SGSN / Inter-CS-GW”, and the COMBINED location registration instruction is used. . Further, the signal from the AS to the HLR has a content indicating “Intra-SGSN / Inter-CS-GW” using the COMBINED location registration signal.

  On the other hand, the second plan is as follows. That is, for the signal from the SGSN to the CS-GW, a parameter indicating “Intra-SGSN” is added to the COMBINED location registration signal, as in the first proposal. In addition, for the signal from the CS-GW to the AS via the I / S-CSCF, the SIP signal is used to indicate “Inter-SGSN / Inter-CS-GW”, and “Intra-SGSN” is set. Add the indicated parameter. Further, for the signal from the AS to the HLR, the COMBINED location registration signal has a content indicating “Inter-SGSN / Inter-CS-GW” and a parameter indicating “Intra-SGSN” is added.

Hereinafter, the first and second plans will be described.
(1st plan)
In the first proposal, when the SGSN does not change, a parameter for identifying that “SGSN has not changed” is added to the COMBINED location registration signal. Further, a parameter for instructing “COMBINED location registration” is added to a signal transmitted from the CS-GW to the AS via the I / S-CSCF. Therefore, when realizing the mobile communication system according to the present example, it is necessary to add or change the function in each node constituting the network.

In FIG. 2, when the SGSN 11 cannot select the CS-GW 13a due to a line failure or the like (step S21), the SGSN 11 selects another CS-GW 13b and performs COMBINED location registration. When this COMBINED location registration is performed, a new parameter indicating that “SGSN has not changed” is added (step S22).
By adding this parameter, when the CS-GW 13b receives the COMBINED location registration signal from the SGSN 11, the CS-GW 13b recognizes that the SGSN has not changed from the new parameter. Therefore, the CS-GW 13b instructs the HLR 10 to register the COMBINED location, although the SGSN 11 has not changed (step S23).

The I / S-CSCF 14 and the AS 15 relay the COMBINED location registration signal from the CS-GW 13b to the HLR 10 (step S24).
When the HLR 10 receives the COMBINED location registration signal from the CS-GW 13b, the HLR 10 recognizes that only the CS-GW has changed, and instructs only the CS-GW to delete the profile information (step S25). As a result, only the profile information stored in the CS-GW 13a is deleted (step S26).

(2nd plan)
In the second plan, when the SGSN does not change, a parameter for identifying “SGSN is not changed” is added to the COMBINED location registration signal. Further, a parameter indicating “Intra-SGSN” is added to the signal transmitted from the CS-GW to the AS via the I / S-CSCF. Therefore, when realizing the mobile communication system according to the present example, it is necessary to add or change the function in each node constituting the network.

In FIG. 3, when the SGSN 11 cannot select the CS-GW 13a due to a line failure or the like (step S21), the SGSN 11 selects another CS-GW 13b and performs COMBINED location registration. When this COMBINED location registration is performed, a new parameter indicating that “SGSN has not changed” is added (step S22).
By adding this parameter, when the CS-GW 13b receives the COMBINED location registration signal from the SGSN 11, the CS-GW 13b recognizes that the SGSN has not changed from the new parameter. Therefore, the CS-GW 13b notifies the HLR 10 that the SGSN has not changed, but the CS-GW has changed (step S23 ′).

The I / S-CSCF 14 and the AS 15 relay the COMBINED location registration signal from the CS-GW 13b to the HLR 10 (step S24).
When the HLR 10 receives the COMBINED location registration signal from the CS-GW 13b, the HLR 10 recognizes that only the CS-GW has changed, and instructs only the CS-GW to delete the profile information (step S25). As a result, only the profile information stored in the CS-GW 13a is deleted (step S26).

(Operation example when the first proposal is adopted)
FIG. 4 is a flowchart showing an operation example of the mobile communication system in the case where the first plan is adopted.
First, it is determined whether the location registration is Intra-SGSN (step S11). As a result of the determination in step S11, if the location registration is not Inter-SGSN location registration but Inter-SGSN location registration (step S11: NO), the existing operation is performed (step S12). That is, since it is an Inter-SGSN, COMBINED location registration is performed.

On the other hand, if the result of determination in step S11 is Intra-SGSN location registration (step S11: YES), it is next determined whether or not the COMBINED location registration is forcibly executed (step S13). That is, it is determined whether the location registration needs to be performed for the HLR even if the area is not changed, such as LICH = Not Confirmed or SDCH = Not Confirmed. As a result of the determination in step S13, if it is not a case where the COMBINED position registration is forcibly executed (step S13: NO), the existing operation is performed (step S14). That is, normal CS location registration is performed.
If the result of the determination in step S13 is a case where the COMBINED location registration is forcibly executed (step S13: YES), a parameter indicating “Intra-SGSN” is set in the COMBINED signal from the SGSN to the CS-GW. (Step S15).

Furthermore, although it is Intra-SGSN, a parameter instructing to perform “COMBINED location registration” is added to the SIP signal transmitted from the CS-GW to the AS via the I / S-CSCF (step S16). By adding this parameter, in the core network, the intra-SGSN performs location registration for the HLR using the COMBINED location registration signal (step S17).
Since it is an Intra-SGSN, AS and HLR do not delete the profile information of the former SGSN (step S18).

(Example of operation when the second plan is adopted)
FIG. 5 is a flowchart showing an operation example of the mobile communication system when the second plan is adopted.
First, it is determined whether the location registration is Intra-SGSN (step S11). As a result of the determination in step S11, if the location registration is not Inter-SGSN location registration but Inter-SGSN location registration (step S11: NO), the existing operation is performed (step S12). That is, since it is an Inter-SGSN, COMBINED location registration is performed.

On the other hand, if the result of determination in step S11 is Intra-SGSN location registration (step S11: YES), it is next determined whether or not the COMBINED location registration is forcibly executed (step S13). That is, it is determined whether or not the location registration needs to be performed for the HLR even if the area has not changed, such as LICH = Not Confirmed or SDCH = Not Confirmed. As a result of the determination in step S13, if it is not a case where the COMBINED position registration is forcibly executed (step S13: NO), the existing operation is performed (step S14). That is, normal CS location registration is performed.
If the result of the determination in step S13 is a case where the COMBINED location registration is forcibly executed (step S13: YES), a parameter indicating “Intra-SGSN” is set in the COMBINED signal from the SGSN to the CS-GW. (Step S15).

Further, a parameter indicating Intra-SGSN is added to the SIP signal transmitted from the CS-GW to the AS via the I / S-CSCF (step S16 ′). By adding this parameter, in the core network, the intra-SGSN performs location registration for the HLR using the COMBINED location registration signal (step S17).
Since it is an Intra-SGSN, AS and HLR do not delete the profile information of the former SGSN (step S18).

(Signal transfer between each device)
Next, with reference to the sequence diagrams of FIG. 6 to FIG. 9, signal exchange between devices (between nodes) constituting the mobile communication system will be described. FIG. 6 and FIG. 7 are sequence diagrams showing signal exchange between devices (between nodes) constituting the mobile communication system in the case of the first proposal. 8 and 9 are sequence diagrams showing signal transmission / reception between devices (between nodes) constituting the mobile communication system in the case of the second proposal. 6 to 9, “additional parameter” is abbreviated as “additional para”.

(A) In case of No. 1 Intra-SGSN, Inter-CS-GW, AS straddling First, the case of no Intra-SGSN, Inter-CS-GW, AS straddling will be described.
FIG. 6 shows devices constituting the mobile communication system of this example, SGSN 11, old SGSN 11 ′, old CS-GW 13a, new CS-GW 13b, old I / S-CSCF 14a, new I / S-CSCF 14b, old AS 15a, It is a sequence diagram which shows signal transmission / reception between new AS15b and HLR10. “Old” indicates that the device corresponds to the area from which the mobile terminal has moved, and “new” indicates that the device corresponds to the area after the mobile terminal has moved. Further, the oval figure in the figure indicates that the profile information P of the subscriber is held in the device (or node).

In FIG. 6, when a mobile terminal (not shown) transmits a COMBINED ATTACH signal or a COMBINED RA / LA UPDATING signal, the SGSN 11 receives the signal (S101). RA (Routing Area) is a packet switching location registration area, and LA (Location Area) is a circuit switching location registration area.
The SGSN 11 transmits BSSAP + COMBINED LOCATION UPDATE REQUEST to the new CS-GW 13b (S102). This BSSAP + COMBINED LOCATION UPDATE REQUEST includes “Intra-SGSN” as an additional parameter.

  When the new CS-GW 13b receives this BSSAP + COMBINED LOCATION UPDATE REQUEST, the new CS-GW 13b transmits SIP REGISTER (Intra-SGSN / Inter-CS-GW) to the AS 15b via the new I / S-CSCF 14b (S103, S104). This SIP REGISTER (Intra-SGSN / Inter-CS-GW) includes “COMBINED location registration” as an additional parameter.

Since the AS 15b is “Intra-SGSN” but is instructed to perform “COMBINED location registration”, the AS 15b transmits MAP_COMBINED UPDATE LOCATION to the HLR 10 in order to perform COMBINED location registration (S105). In this MAP_COMBINED UPDATE LOCATION, “Intra-SGSN” is included as an additional parameter.
Here, when a MAP ISD (Inter-Site Distance) REQ is transmitted from the HLR 10 to the AS 15b (S106), the MAP is transmitted from the AS 15b to the HLR 10.

An ISD RESP is returned (S107). Thereafter, MAP_COMBINED UPDATE LOCATION RESP (abbreviated as MAP CUL RESP in the drawing) is returned from the HLR 10 to the AS 15b (S108).
The AS 15b transmits Notify (hereinafter abbreviated as SIP Notify) by the SIP signal to the old I / S-CSCF 14a (S109).
Thereafter, the AS 15b determines from the SIP setting parameters that it is “Intra-SGSN”, and CL (Cancel Location) is performed only for the VLR (S110). For this reason, AS15b transmits MAP_CANCEL LOCATION (VLR) to old CS-GW13a (S111). Thereby, the old CS-GW 13a deletes the held profile information P (S112), and returns a MAP_CANCEL LOCATION RESP as a response (S113).

Thereafter, the AS 15b transmits 200 OK (hereinafter abbreviated as SIP 200 OK) by SIP signal to the new I / S-CSCF 14b (S114), and the new I / S-CSCF 14b holds the profile information (S115). Further, the new I / S-CSCF 14b transmits SIP 200 OK to the new CS-GW 13b (S116), and the new CS-GW 13b holds the profile information (S117).
The new CS-GW 13b returns BSSAP + COMBINED LOCATION UPDATE ACCEPT to the SGSN 11 (S118). The SGSN 11 transmits a COMBINED ATTACH ACCEPT signal or a COMBINED RA / LA UPDATING ACCEPT signal to a mobile terminal (not shown) (S119).

After the HLR 10 is restarted, the stored data may be up to 15 minutes old. In this case, the HLR address needs to be changed. Therefore, when an additional parameter is added and the SGSN address held in the HLR 10 has changed, CL (Cancel Location) is transmitted to the old SGSN 11 ′ (S120).
In this case, there is a high possibility that there is actually no profile information in the old SGSN, but there is a possibility that the profile information is retained. Therefore, the HLR 10 transmits MAP_CANCEL LOCATION (VLR) to the old SGSN 11 ′ (S121). The old SGSN 11 ′ that received this deletes the profile information (S122). Thereafter, the old SGSN 11 ′ returns a MAP_CANCEL LOCATION RESP to the HLR 10 (S123). This completes the process.

(B) In case of Intra-SGSN, Inter-CS-GW, AS straddling in first plan Next, a case of Intra-SGSN, Inter-CS-GW, ASN straddling will be described.
FIG. 7 shows devices constituting the mobile communication system of this example, SGSN 11, old SGSN 11 ′, old CS-GW 13a, new CS-GW 13b, old I / S-CSCF 14a, new I / S-CSCF 14b, old ASN 15a, It is a sequence diagram which shows signal transmission / reception between new ASN15b and HLR10. “Old” indicates that the device corresponds to the area from which the mobile terminal has moved, and “new” indicates that the device corresponds to the area after the mobile terminal has moved. Further, the oval figure in the figure indicates that the profile information P of the subscriber is held in the device (or node).

In FIG. 7, when a mobile terminal (not shown) transmits a COMBINED ATTACH signal or a COMBINED RA / LA UPDATING signal, the SGSN 11 receives the signal (S101).
The SGSN 11 transmits BSSAP + COMBINED LOCATION UPDATE REQUEST to the new CS-GW 13b (S102). This BSSAP + COMBINED LOCATION UPDATE REQUEST includes “Intra-SGSN” as an additional parameter.

  When the new CS-GW 13b receives this BSSAP + COMBINEDLOCATION UPDATE REQUEST, the new CS-GW 13b transmits SIP REGISTER (Intra-SGSN / Inter-CS-GW) to the ASN 15b via the new I / S-CSCFb (S103, S104). This SIP REGISTER (Intra-SGSN / Inter-CS-GW) includes “COMBINED location registration” as an additional parameter.

  Since the AS 15b is “Intra-SGSN” but is instructed to perform “COMBINED location registration”, the AS 15b transmits MAP_COMBINED UPDATE LOCATION to the HLR 10 in order to perform COMBINED location registration (S105). In this MAP_COMBINED UPDATE LOCATION, “Intra-SGSN” is included as an additional parameter.

When the HLR 10 receives the MAP_COMBINED UPDATE LOCATION, the HLR 10 performs CL according to the following determination (S105a).
(1) When there is an additional parameter and there is no SGSN change (in the case of normal LICH operation), VLR is designated and CL is transmitted.
(2) When there is an additional parameter and there is an SGSN change (in the case of SGSN unmatch), VLR is designated and CL is transmitted, and CL is transmitted to the old SGSN.
(3) When there is no additional parameter (in the case of normal COMMBINE), CL is transmitted by specifying UMSC.

In accordance with the above determination, the HLR 10 transmits MAP_CANCEL LOCATION REQUEST to the new AS 15b (S105b). The new AS 15b transmits SIP NOTIFY to the old I / S-CSCF 14a (S109).
Thereafter, the new AS 15b transmits MAP_CANCEL LOCATION (VLR) to the old CS-GW 13a (S111). Thereby, the old CS-GW 13a deletes the held profile information P (S112), and returns a MAP_CANCEL LOCATION RESP as a response (S113). The new AS 15b transmits MAP_CANCEL LOCATION RESPONSE to the HLR 10 (S113a).

  Here, when a MAP ISD (Inter-Site Distance) REQ is transmitted from the HLR 10 to the AS 15b (S106), the AS 15b holds the subscriber profile information (S106a), and then the MAP ISD RESP is returned from the AS 15b to the HLR 10 ( S107). Thereafter, MAP_COMBINED UPDATE LOCATION RESP (abbreviated as MAP CUL RESP in the drawing) is returned from the HLR 10 to the AS 15b (S108).

Thereafter, the AS 15b transmits SIP 200 OK to the new I / S-CSCF 14b (S114), and the new I / S-CSCF 14b holds the profile information (S115). Further, the new I / S-CSCF 14b transmits SIP 200 OK to the new CS-GW 13b (S116), and the new CS-GW 13b holds the profile information (S117).
The new CS-GW 13b returns BSSAP + COMBINED UPDATE ACCEPT to the SGSN 11 (S118). The SGSN 11 transmits a COMBINED ATTACH ACCEPT signal or a COMBINED RA / LA UPDATING ACCEPT signal to a mobile terminal (not shown) (S119). This completes the process.

(C) In case of the second plan, Intra-SGSN, Inter-CS-GW, and no AS straddling FIG. 8 shows devices constituting the mobile communication system of this example, SGSN 11, old SGSN 11 ′, old CS- It is a sequence diagram which shows signal transmission / reception among GW13a, new CS-GW13b, old I / S-CSCF14a, new I / S-CSCF14b, old AS15a, new AS15b, and HLR10. “Old” indicates that the device corresponds to the area from which the mobile terminal has moved, and “new” indicates that the device corresponds to the area after the mobile terminal has moved. Further, the oval figure in the figure indicates that the profile information P of the subscriber is held in the device (or node).

  In this example, the difference from the case of FIG. 6 is that the signal transmitted from the new CS-GW 13b is different. In this example, the SIP REGISTER (Intra-SGSN / Inter-CS-GW) transmitted by the new CS-GW 13b includes “Intra-SGSN” as an additional parameter (S103 ′). The AS 15b is “Inter-SGSN”, but “Intra-SGSN” is set as an additional parameter, so COMBINED location registration is performed. Other processes are the same as those in FIG.

(D) In case of Intra-SGSN, Inter-CS-GW, AS straddling in second plan Next, a case of Intra-SGSN, Inter-CS-GW, AS straddling will be described.
FIG. 9 shows devices constituting the mobile communication system of this example, SGSN 11, old SGSN 11 ′, old CS-GW 13a, new CS-GW 13b, old I / S-CSCF 14a, new I / S-CSCF 14b, old AS 15a, It is a sequence diagram which shows signal transmission / reception between new AS15b and HLR10. “Old” indicates that the device corresponds to the area from which the mobile terminal has moved, and “new” indicates that the device corresponds to the area after the mobile terminal has moved. Further, the oval figure in the figure indicates that the profile information P of the subscriber is held in the device (or node).

  In this example, the difference from the case of FIG. 7 is that the signal transmitted from the new CS-GW 13b is different. In this example, the SIP REGISTER (Intra-SGSN / Inter-CS-GW) transmitted by the new CS-GW 13b includes “Intra-SGSN” as an additional parameter (S103 ′). The AS 15b is “Inter-SGSN”, but “Intra-SGSN” is set as an additional parameter, so COMBINED location registration is performed. Other processes are the same as those in FIG.

(Modification 1)
In the above example, the case where the combined location registration signal is transmitted has been described. However, the present invention is not limited to this case, and the present invention can be similarly applied to the case where the location registration signal is transmitted even though the SGSN is not changed. Is clear.
Here, the case where said 2nd plan is applied about the network comprised by SGSN, VLR, and HLR is demonstrated.

In FIG. 10, when the SGSN 11 cannot select the VLR 21 due to a line failure or the like (step S21a), the SGSN 11 selects another VLR 22 and performs COMBINED location registration. When this COMBINED location registration is performed, a new parameter indicating that “SGSN has not changed” is added (step S22a).
By adding this parameter, when the VLR 22 receives the COMBINED location registration signal from the SGSN 11, the VLR 22 recognizes that the SGSN has not changed from the new parameter. Therefore, the VLR 22 notifies the HLR 10 that the SGSN has not changed, but the VLR has changed (step S23a).

When receiving the COMBINED location registration signal from the VLR 22, the HLR 10 recognizes that only the VLR has changed, and instructs only the VLR to delete profile information (step S25a). As a result, only the profile information held in the VLR 21 is deleted (step S26a).
FIG. 11 is a flowchart showing an operation example of the mobile communication system when the above second plan is adopted.

  First, it is determined whether the location registration is Intra-SGSN (step S11a). As a result of the determination in step S11a, if the location registration is not Inter-SGSN location registration but Inter-SGSN location registration (step S11a: NO), the existing operation is performed (step S12a). That is, since it is an Inter-SGSN, COMBINED location registration is performed.

  On the other hand, as a result of the determination in step S11a, if the location registration is Intra-SGSN (step S11a: YES), it is then determined whether the COMBINED location registration is forcibly executed (step S13a). That is, it is determined whether or not the location registration needs to be performed for the HLR even if the area has not changed, such as LICH = Not Confirmed or SDCH = Not Confirmed. If the result of determination in step S13a is not a case where the COMBINED location registration is forcibly executed (step S13a: NO), the existing operation is performed (step S14a). That is, normal CS location registration is performed.

If the result of determination in step S13a is that the COMBINED location registration is forcibly executed (step S13a: YES), a parameter indicating “Intra-SGSN” is set in the COMBINED signal from SGSN to VLR (step S13a: YES). S15a). The VLR performs location registration with respect to the HLR using the COMBINED location registration signal even in Intra-SGSN (step S17a).
Since it is an Intra-SGSN, the HLR does not delete the profile information of the former SGSN (step S18a).

Here, FIG. 12 is a sequence diagram showing signal transmission / reception between devices (between nodes) when the second proposal is applied to a network configured by SGSN, VLR, and HLR. In FIG. 12, “additional parameter” is abbreviated as “additional para”.
FIG. 12 is a sequence diagram showing signal transmission / reception among the SGSN 11, the old SGSN 11 ′, the old VLR 21, the new VLR 22, and the HLR 10, which are devices constituting the mobile communication system of this example. “Old” indicates that the device corresponds to the area from which the mobile terminal has moved, and “new” indicates that the device corresponds to the area after the mobile terminal has moved. Further, the oval figure in the figure indicates that the profile information P of the subscriber is held in the device (or node).

In FIG. 12, when a mobile terminal (not shown) transmits a COMBINED ATTACH signal or a COMBINED RA / LA UPDATING signal, the SGSN 11 receives the signal (S101).
The SGSN 11 transmits BSSAP + COMBINED LOCATION UPDATE REQUEST to the new VLR 22 (S102). This BSSAP + COMBINED LOCATION UPDATE REQUEST includes “Intra-SGSN” as an additional parameter.

When the new VLR 22 receives this BSSAP + COMBINED LOCATION UPDATE REQUEST, the new VLR 22 transmits SIP REGISTER (Intra-SGSN / Inter-CS-GW) to the HLR 10 (S103 ′). This SIP REGISTER (Intra-SGSN / Inter-CS-GW) includes “Intra-SGSN” as an additional parameter.
Here, MAP_CANCEL LOCATION (VLR) is transmitted from the HLR 10 to the old VLR 21 (S111). As a result, the old VLR 21 deletes the held profile information P (S112), and returns a MAP_CANCEL LOCATION RESP as a response (S113).

  Thereafter, the HLR 10 transmits SIP 200 OK to the new VLR 22 (S116), and the new VLR 22 holds the profile information (S117). The new VLR 22 returns BSSAP + COMBINED LOCATION UPDATE ACCEPT to the SGSN 11 (S118). The SGSN 11 transmits a COMBINED ATTACH ACCEPT signal or a COMBINED RA / LA UPDATING ACCEPT signal to a mobile terminal (not shown) (S119).

After the HLR 10 is restarted, the stored data may be up to 15 minutes old. In this case, the HLR address needs to be changed. Therefore, when an additional parameter is added and the SGSN address held in the HLR 10 has changed, CL (Cancel Location) is transmitted to the old SGSN 11 ′ (S120).
In this case, there is a high possibility that there is actually no profile information in the old SGSN, but there is a possibility that the profile information is retained. Therefore, the HLR 10 transmits MAP_CANCEL LOCATION (VLR) to the old SGSN 11 ′ (S121). The old SGSN 11 ′ that received this deletes the profile information (S122). Thereafter, the old SGSN 11 ′ returns a MAP_CANCEL LOCATION RESP to the HLR 10 (S123). This completes the process.

  In the above example, the SGSN suppresses transmission of a deletion instruction signal for deleting profile information so as not to delete the profile information. As a modification thereof, the SGSN may determine the received deletion instruction signal, and may not delete the profile information, for example, by controlling to accept only the deletion instruction signal from the intended device.

(Modification 2)
Next, Modification 2 will be described. In the second modification, the HLR instructs the deletion of the profile information while considering the new / old visited nodes.
In FIG. 13, when the SGSN 11 cannot select the VLR 21 due to a line failure or the like (step S21a), the SGSN 11 selects another VLR 22 and performs COMBINED location registration. When this COMBINED location registration is performed, a new parameter indicating that “SGSN has not changed” is added (step S22a).
When the VLR 22 receives the COMBINED location registration signal from the SGSN, the VLR 22 performs COMBINED location registration in the HLR 10 (S23b).

Here, it is assumed that the HLR 10 recognizes the SGSN and VLR that it thinks are currently in the area. When the HLR 10 compares the SGSN and VLR profile information notified by the COMBINED location registration signal with the profile information stored in the HLR 10 itself, and determines that the area has changed, only for the old area An instruction to delete the profile information is given (S25b). In this example, only the VLR is instructed to delete profile information. As a result, only the profile information held in the VLR 21 is deleted (step S26a).
As described above, the HLR 10 has the “new SGSN” and “new VLR” notified by the MAP_COMBINED UPDATE LOCATION REQUEST, the “current SGSN” held by itself, and the “present VLR”. ”. Then, it instructs the node whose location has changed to transmit a cancel signal.

FIG. 14 is a flowchart showing an operation example of the mobile communication system when the above second plan is adopted.
First, it is determined whether the location registration is Intra-SGSN (step S11a). As a result of the determination in step S11a, if the location registration is not Inter-SGSN location registration but Inter-SGSN location registration (step S11a: NO), the existing operation is performed (step S12a). That is, since it is an Inter-SGSN, COMBINED location registration is performed.

  On the other hand, as a result of the determination in step S11a, if the location registration is Intra-SGSN (step S11a: YES), it is then determined whether the COMBINED location registration is forcibly executed (step S13a). That is, it is determined whether or not the location registration needs to be performed for the HLR even if the area has not changed, such as LICH = Not Confirmed or SDCH = Not Confirmed. If the result of determination in step S13a is not a case where the COMBINED location registration is forcibly executed (step S13a: NO), the existing operation is performed (step S14a). That is, normal CS location registration is performed.

If the result of determination in step S13a is that the COMBINED location registration is forcibly executed (step S13a: YES), a parameter indicating “Intra-SGSN” is set in the COMBINED signal from SGSN to VLR (step S13a: YES). S15a). The VLR 22 performs location registration with respect to the HLR 10 using the COMBINED location registration signal even in Intra-SGSN (step S17a). When the HLR 10 compares the SGSN and VLR profile information notified by the COMBINED location registration signal with the profile information stored in itself, and determines that the area has changed, it joins only the former area. Is instructed to delete the user profile information (step S17b).
Since it is an Intra-SGSN, the HLR does not delete the profile information of the former SGSN (step S18a).

Here, FIG. 15 is a sequence diagram showing signal transmission / reception between devices (between nodes) when the second proposal is applied to a network configured by SGSN, VLR, and HLR. In FIG. 15, “additional parameter” is abbreviated as “additional para”.
FIG. 15 is a sequence diagram showing signal transmission / reception among the SGSN 11, the old SGSN 11 ′, the old VLR 21, the new VLR 22, and the HLR 10, which are devices constituting the mobile communication system of this example. “Old” indicates that the device corresponds to the area from which the mobile terminal has moved, and “new” indicates that the device corresponds to the area after the mobile terminal has moved. Further, the oval figure in the figure indicates that the profile information P of the subscriber is held in the device (or node).

In FIG. 15, when a mobile terminal (not shown) transmits a COMBINED ATTACH signal or a COMBINED RA / LA UPDATING signal, the SGSN 11 receives the signal (S101).
The SGSN 11 transmits BSSAP + COMBINED LOCATION UPDATE REQUEST to the new VLR 22 (S102). This BSSAP + COMBINED LOCATION UPDATE REQUEST includes “Intra-SGSN” as an additional parameter.

When the new VLR 22 receives this BSSAP + COMBINED LOCATION UPDATE REQUEST, the new VLR 22 transmits SIP REGISTER (Intra-SGSN / Inter-CS-GW) to the HLR 10 (S103 ′). This SIP REGISTER (Intra-SGSN / Inter-CS-GW) includes “Intra-SGSN” as an additional parameter.
Here, MAP_CANCEL LOCATION (VLR) is transmitted from the HLR 10 to the old VLR 21 (S111). As a result, the old VLR 21 deletes the held profile information P (S112), and returns a MAP_CANCEL LOCATION RESP as a response (S113).

Thereafter, the HLR 10 transmits SIP 200 OK to the new VLR 22 (S116), and the new VLR 22 holds the profile information (S117). The new VLR 22 returns BSSAP + COMBINED LOCATION UPDATE ACCEPT to the SGSN 11 (S118). The SGSN 11 transmits a COMBINED ATTACH ACCEPT signal or a COMBINED RA / LA UPDATING ACCEPT signal to a mobile terminal (not shown) (S119).
After the HLR 10 is restarted, the stored data may be up to 15 minutes old. In this case, the HLR address needs to be changed. Therefore, when an additional parameter is added and the SGSN address held in the HLR 10 has changed, CL (Cancel Location) is transmitted to the old SGSN 11 ′ (S120).

  In this case, there is a high possibility that there is actually no profile information in the old SGSN, but there is a possibility that the profile information is retained. Therefore, the HLR 10 transmits MAP_CANCEL LOCATION (VLR) to the old SGSN 11 '(S121). The old SGSN 11 ′ that received this deletes the profile information (S 122). Thereafter, the old SGSN 11 ′ returns a MAP_CANCEL LOCATION RESP to the HLR 10 (S 123). This completes the process. The above can be applied to IMS as well as standard SGSN, MSC, and HLR.

(Location registration method)
In the mobile communication system described above, the following location registration method is realized. That is, when a location registration signal related to a mobile terminal is received, an instruction to delete the subscriber profile information related to the mobile terminal is sent to the exchange corresponding to the old service area where the mobile terminal was located. A first step in which the first device transmits a deletion instruction signal including the position indication signal to be transmitted even when the area where the mobile terminal is located has not been changed. A location registration method is realized that includes a second step in which a second device transmits to the first device, including transmission suppression information for suppressing transmission. By this method, even in the case of Intra-SGSN, the COMBINED location registration signal can be used without causing a problem.

(Summary)
As described above, by adding a parameter and making it function as a flag indicating that the parameter should not be deleted and a flag indicating that the deletion is prohibited, the SGSN holds when the LICH flag is set (flag is on). When the mobile terminal location registration is forcibly performed, such as when the subscriber profile information is not confident in the accuracy (subscriber profile information may not be accurate), the SGSN has not changed. However, when performing COMBINED location registration, the mobile terminal can be identified by notifying the SGSN, AS, and HLR that it is instructed to delete the subscriber profile information held in the SGSN. Do not disturb the communication used. Therefore, according to the present invention, since the COMBINED location registration signal can be used even in the forced location registration when the SGSN has not changed, the signal is compared with the case where the CS / PS single location registration signal is used. Since the number can be reduced, the load on the HLR can be reduced.

  It should be noted that the scope of the present invention is not limited to the illustrated and described exemplary embodiments, but includes all embodiments that provide the same effects as those intended by the present invention. Furthermore, the scope of the invention is not limited to the combinations of features of the invention defined by the claims, but can be defined by any desired combination of particular features among all the disclosed features.

DESCRIPTION OF SYMBOLS 1 1st apparatus 2 2nd apparatus 3 Switch 10 HLR
11, 12 SGSN
13a, 13b, 21, 22 CS-GW
14 I / S-CSCF
15 AS
MT mobile terminal

Claims (5)

Deletion including an instruction to delete subscriber profile information related to the mobile terminal to an exchange corresponding to the old area where the mobile terminal was located when a location registration signal related to the mobile terminal is received A first device for transmitting an instruction signal;
The location registration signal to be transmitted even if the area where the mobile terminal is located has not changed, includes transmission suppression information for suppressing transmission of the deletion instruction signal by the first device, A second device transmitting to the device;
A mobile communication system comprising: In claim 1,
The mobile communication system, wherein the location registration signal is a COMBINED location registration signal for collectively performing location registration processing relating to line connection and location registration processing relating to packet connection. In claim 1 or 2,
The location registration signal to be transmitted even when the mobile terminal's coverage area has not changed is transmitted when “Location Information Configured in HLR” of the subscriber profile information is set to “Not Confirmed”. A mobile communication system, characterized by being a location registration signal. In claim 1 or 2,
The location registration signal to be transmitted even when the area where the mobile terminal is located has not been changed is a location registration signal that is transmitted when the subscriber profile information held in the exchange may not be accurate. A mobile communication system, comprising: Deletion including an instruction to delete subscriber profile information related to the mobile terminal to an exchange corresponding to the old area where the mobile terminal was located when a location registration signal related to the mobile terminal is received A first step in which the first device transmits an instruction signal;
The location registration signal to be transmitted even if the area where the mobile terminal is located has not changed, includes transmission suppression information for suppressing transmission of the deletion instruction signal by the first device, A second step transmitted by the second device to the device;
The location registration method characterized by including.

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