JP2019080105A - Congestion control method, congestion control program, congestion control device, and network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a congestion control method, a congestion control program, a congestion control device, and a network system capable of rapidly regulating signal transmission causing congestion in any form. SOLUTION: A congestion control method is a method of controlling a congestion state of a second network by signals transmitted from a plurality of terminals in the first network, in which a computer uses a communication function of a network layer to provide congestion information regarding the congestion state. The process of acquiring and outputting to the application layer, the process of accepting the setting of the restricted form of signal transmission for each first network or each terminal by the communication function of the application layer, and the communication function of the application layer for congestion information. It is a method of selecting a regulation form based on the regulation form and transmitting a message for restricting signal transmission to the first network according to the regulation form. [Selection diagram] Fig. 2

Description

  The present invention relates to a congestion control method, a congestion control program, a congestion control device, and a network system.

  The technology of IoT (Internet Of Things) for connecting various devices such as sensors to the Internet is widespread. For wide area communication with IoT devices, for example, it is considered to use a network of communication carriers that provide communication services such as smartphones (hereinafter referred to as “carrier network”). In response to this, for example, in order to determine the 020 number band dedicated to the IoT device, movements such as revision of ministerial ordinance by the Ministry of Internal Affairs and Communications are seen.

  In the service using IoT, for example, a wireless network composed of a plurality of MTC (Machine Type Communication) terminals (for example, see Patent Documents 1 and 2) installed in the field of manufacturing industry, social infrastructure, and transportation / distribution, etc. Connected to the carrier network via the IoT gateway. As this wireless network, for example, LPWA (Low Power Wide Area) can be mentioned. The data collected by each MTC terminal is collected via a carrier network to a data center or the like, where services such as data analysis are provided.

JP 2017-85516 A JP, 2014-78987, A

  For example, when a disaster occurs, it is conceivable that a large number of MTC terminals present in the disaster area transmit signals such as an abnormal notification toward the carrier network in a chaotic and massive manner. At this time, for example, in a mobile switching center (MSC: Mobile Switching Center) in a carrier network, the load may increase due to a signal from the MTC terminal, and a congestion state may occur.

  On the other hand, in the carrier network, communication to the MTC terminals in the disaster area is restricted so that the congestion state is eliminated, but in the above case, the signal transmission from the MTC terminals continues for a long time. Communication to the area may not be possible for a long time.

  Also, in the carrier network, prior to the regulation of communication, a communication path for bypassing the MSC in a congested state or a backup node at the bypass destination is searched, and if there is the corresponding communication path or backup node, the communication is regulated Instead, communication path switching is performed. However, when there is congestion caused by a disaster, there are many cases in which the detourable communication path and the backup node at the detour destination are also in the congested state, and even if there is something not in the congested state, the search processing and switching processing takes a long time After all, it is difficult to quickly restore communication to the disaster area.

  On the other hand, if the MTC terminal itself, which is the cause of the congestion state, detects the congestion state of the MSC, it can quickly restrict its own signal transmission according to the detection, but by implementing that function Another problem arises that the cost of MTC terminals increases. Furthermore, despite the fact that MTC terminals are used in a wide variety of services, if the signal transmission of each MTC terminal is regulated in a uniform manner, it may affect the quality of service.

  An object of the present invention is to provide a congestion control method, a congestion control program, a congestion control device, and a network system capable of quickly restricting signaling caused by congestion in any form.

  In one aspect, a congestion control method includes a communication function of a network layer, an application layer, in a congestion control method for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks. Processing the computer having the communication function of acquiring the congestion information related to the congestion state by the communication function of the network layer and outputting the congestion information to the application layer; The restriction form is selected based on the congestion information by the process of accepting the setting of the restriction form of transmission of the signal for each of the network or each of the plurality of terminals, and the selection form is selected based on the congestion information. The one or more messages for restricting the transmission of the signal according to the restriction form A method for executing a process of transmitting to the first network.

  In one aspect, the congestion control program includes a communication function of a network layer, an application layer in a congestion control program for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks. The communication function of the network layer acquires congestion information related to the congestion state to a computer having the communication function of: and outputting the congestion information to the application layer, and the communication function of the application layer The setting of the restriction form of transmission of the signal is received for each or each of the plurality of terminals, the restriction form is selected based on the congestion information by the communication function of the application layer, and the restriction form is selected according to the selected restriction form. Said one or more messages regulating messages transmission To the network, a program for executing the processing.

  In one aspect, the congestion control device executes a communication function of a network layer in a congestion control device that controls a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks. A first functional unit, and a second functional unit that executes a communication function of an application layer, the first functional unit acquiring congestion information related to the congestion state and outputting the congestion information to the second functional unit; The second functional unit receives, for each of the one or more first networks or each of the plurality of terminals, the setting of the restriction form of transmission of the signal, selects the restriction form based on the congestion information, and selects the restriction form. A message is provided to the one or more first networks to restrict transmission of the signal according to the restriction form.

  In one aspect, a network system comprises: a congestion control device for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in the one or more first networks; the one or more first networks; 2) having one or more gateway devices respectively connecting the two networks, wherein the congestion control device comprises: a first functional unit that executes the communication function of the network layer; and a second functional unit that performs the communication function of the application layer The first functional unit acquires congestion information related to the congestion state and outputs the congestion information to the second functional unit, and the second functional unit is configured to receive each of the one or more first networks or the plurality of terminals Setting the regulation form of transmission of the signal, and selecting the regulation form based on the congestion information; Send a message to regulate the transmission of signals to the one or more gateway devices, said one or more gateways, in accordance with the message, to regulate the transmission of the signal to the plurality of terminals.

  In one aspect, congestion-causing signaling can be quickly regulated in any manner.

FIG. 1 is a block diagram showing an example of a network system. It is a figure which shows an example of the control operation | movement of signal transmission. It is a figure which shows the example of each parameter of TFC (Transfer Controlled) signal and RCT (signalling-Route-set-Congestion-Test) signal. It is a figure which shows an example of the control release operation | movement of signal transmission. It is a block diagram which shows an example of a SMSC (Short Message Service Center). It is a figure which shows an example of MTP (Message Transfer Part) service primitive. It is a figure which shows an example of the setting of a message database. It is a figure which shows an example of the parameter of a message transmission request. It is a block diagram which shows an example of an IoT gateway apparatus. It is a block diagram which shows an example of a MTC terminal. It is a flow chart which shows an example of initial setting processing. It is a flowchart which shows an example of a transmission process of a regulation message. It is a flow chart which shows an example of transmission processing of a regulation cancellation message. It is a flowchart which shows an example of a reception process of the control message of an IoT gateway apparatus, and a deregulation message. It is a flowchart which shows an example of the process of the transmission control of a MTC terminal, and a control cancellation. It is a figure which shows the example of transmission control.

  FIG. 1 is a block diagram showing an example of a network system. The network system includes carrier networks 90 and 91, a plurality of IoT gateway devices (IoT-GW) 2, and a plurality of wireless networks 92. The wireless network 92 is an example of a first network, and the carrier network is an example of a second network. Note that the congestion control method described below can be performed by only one of the carrier networks 90 and 91.

  In the wireless network 92, for example, a wireless communication method such as Low Power Wide Area (LPWA) is used, and a plurality of MTC terminals 3 as an example of the terminal communicate via the IoT-GW 2 by wireless communication. The IoT-GW 2 is an example of a gateway device, and connects the carrier networks 90 and 91 and a plurality of wireless networks 92. Although a plurality of wireless networks 92 are connected to each carrier network 90, 91 via a plurality of IoT-GWs 2, one wireless network 92 may be connected via one IoT-GW 2 .

  A mobile subscriber integrated services digital network number (MSISDN), which is a mobile telephone number, is assigned to the IoT-GW 2 as an example of identification information. Therefore, regardless of the number of MTC terminals 3 connected to the IoT-GW 2, it is possible to suppress the number of MSISDNs required for each wireless network 92 to one. Although each MTC terminal 3 is connected to the carrier networks 90 and 91 via the IoT-GW 2 in this example, even if the MTC terminals 3 are directly connected to the carrier networks 90 and 91 not via the IoT-GW 2 Good. In this case, MSISDN is allocated to each MTC terminal 3.

  Each carrier network 90, 91 performs various settings from the SCS (Service Capability Server) 5. The setting includes setting of a restriction form of signal transmission and registration of primitive reception as described later.

  Each carrier network 90, 91 includes an SMSC 1, a SIGTRAN gateway device (SIGTRAN-GW) 40, a Gate Mobile Switching Center (GMSC) 41, and a plurality of MSCs (Mobile Switching Centers) 42. Furthermore, in each carrier network 90, 91, MTC (Machine Type Communication) -IWF (Inter-Working Function) 43, HLR (Home Location Register) / HSS (Home Subscriber Register) 44, VLR (Visitor Location Register). And 45 are included.

  Further, each wireless network 92 includes a plurality of MTC terminals 3. The MTC terminal 3 may be, for example, a wireless terminal equipped with a sensor, but is not limited thereto.

  The SMSC 1 is an example of a congestion control device, and controls congestion states of the carrier networks 90 and 91 by signals transmitted from a plurality of MTC terminals 3 in each wireless network 92. The SMSC 1 detects congestion of the MSC 42 based on the TFC signal from the SIGTRAN-GW 40, and transmits a restriction message for restricting signal transmission based on SMS (Short Message Service) to the first network in response to the detection.

  The SMSC 1 receives the setting of the restriction form for signal transmission for each wireless network 92 or each MTC terminal 3 from the SCS 5 via the MTC-IWF 43. The SMSC 1 selects a restriction form based on congestion information included in the TFC signal, and transmits a restriction message for restricting transmission of the signal according to the restriction form.

  The SIGTRAN-GW 40 is connected between the SMSC 1 and the GMSC 41 and relays SMS communication between the SMSC 1 and the wireless network 92. The SIGTRAN-GW 40 also performs congestion control in accordance with the SIGTRAN protocol. For example, the SIGTRAN-GW 40 transmits a signal to each MSC 42, and detects a congestion state of the MSC 42 when the delay time until receiving the response signal exceeds a predetermined threshold.

  When the SIGTRAN-GW 40 detects a congestion state, it transmits a TFC signal (transfer control signal) containing congestion information including the address of the MSC 42 in congestion state and congestion level to the SMSC 1. The congestion control according to the MTP3 protocol is defined, for example, in TTC (Telecommunications Technology Committee) standard Q.704.

  The GMSC 41 is connected between the SIGTRAN-GW 40 and the plurality of MSCs 42 and relays communication between the SMSC 1 and the wireless network 92. Also, the GMSC 41 relays SMS communication between the two carrier networks 90 and 91. The relay by the GMSC 41 is used, for example, when the number portability of the mobile telephone number (MSISDN) of the MTC terminal 3 becomes possible.

  In this case, for example, the connection destination of the MTC terminal 3 may be changed from the one carrier network 90 to the IoT-GW 2 of the other carrier network 91. In this case, the GMSC 41 relays the SMS message from the SMSC 1 to the MTC terminal 3 via the GMSC 41 of the other carrier network 90, 91.

  The MSC 42 is an example of a switch, and is connected between the GMSC 41 and the plurality of IoT-GWs 2 to relay communication between the SMSC 1 and the wireless network 92. When the MSC 42 receives a large amount of signals of the MTC terminal 3 from each IoT-GW 2, the load of the exchange process increases, and thus the MSC 42 is in a congested state. When the MSC 42 receives a signal from the SIGTRAN-GW 40 in a congestion state, it takes a lot of time to transmit its response signal to the SIGTRAN-GW 40.

  The IoT-GW 2 is connected between the MSC 42 and the plurality of IoT-GWs 2 and relays communication between the SMSC 1 and the wireless network 92. When the IoT-GW 2 receives the restriction message from the SMSC 1, the IoT-GW 2 instructs the MTC terminal 3 subject to restriction to restrict signal transmission according to the restriction message. The MTC terminal 3 stops the transmission of the signal according to the instruction of the regulation of the signal transmission.

  The IoT-GW 2 is pre-assigned an MSISDN (mobile phone number), and performs SMS communication with the SMSC 1 based on the MSISDN. The MSISDN may be allocated to each of the MTC terminals 3. In this case, the MTC terminal 3 receives a restriction message from the SMSC 1 via the IoT-GW 2, and stops transmission of a signal in response to the reception.

  The IoT-GW 2 can change the connected carrier networks 90 and 91 according to the SMS message from the SMSC 1 as described later. For example, the IoT-GW 2 accommodated in the MSC 42 of one carrier network 90 is accommodated in the MSC 42 of the other carrier network 91 according to the SMS message (see symbol L). At this time, each MTC terminal 3 under the IoT-GW 2 needs to be assigned an MSISDN for each of the carrier networks 90, 91, and the MSISDN according to the carrier networks 90, 91 of the accommodation destination MSC 42 communicates. Used.

  Further, the SMSC 1 transmits an RCT signal to the SIGTRAN-GW 40, and detects that the congestion state of the MSC 42 has been eliminated, when a TFC signal is not received from the SIGTRAN-GW 40 within a predetermined time as a response. When the SMSC 1 detects that the congestion state has been eliminated, the SMSC 1 transmits, to the wireless network 92, a restriction release message for releasing the restriction on the signal transmission.

  When the IoT-GW 2 receives the restriction release message from the SMSC 1, the IoT-GW 2 instructs the MTC terminal 3 to be subjected to the restriction release according to the restriction release message to release the restriction on the signal transmission. The MTC terminal 3 resumes signal transmission in accordance with the instruction to release the restriction on signal transmission.

  Also, the HLR / HSS 44 is connected to the GMSC 41, and the VLR 45 is connected to the MSC 42. The HLR / HSS 44 and the VLR 45 manage location information of communication devices accommodated in each MSC 42. That is, the HLR / HSS 44 and the VLR 45 manage the position of the IoT-GW 2 or the MTC terminal 3.

  More specifically, the HLR / HSS 44 and the VLR 45 manage the address of the MSC 42 and the MSISDN allocated to the IoT-GW 2 and the MTC terminal 3 in association with each other. The SMSC 1 cooperates with the HLR / HSS 44 and the VLR 45 to acquire location information of the MSC 42 in a congested state, and identifies the IoT-GW 2 and the MTC terminal 3 accommodated in the MSC 42 by using the MSISDN. The SMSC 1 selects the regulation form according to the MSISDN from the regulation form set in advance.

  FIG. 2 is a diagram showing an example of the regulation operation of signal transmission. “A” to “F” indicate the order of operation. The code La indicates the protocol stack configuration of the SMSC 1, the code Lb indicates the protocol stack configuration of the SIGTRAN-GW 40, and the code Lc indicates the protocol stack configuration of the MSC 42. Each protocol stack La to Lc includes an SS7 signaling protocol for sending and receiving SMS messages.

  The protocol stack configuration La of the SMSC 1 includes a stream control transmission protocol (SCTP), a message transfer protocol 2 user adaptation layer (M2UA), an MTP 3 and a signaling connection control part (SCCP). Furthermore, the protocol stack configuration La of SMSC 1 includes a Transaction Capability Application Part (TCAP), a Mobile Application Part (MAP), and an SMS application (SMS APL).

  Of the protocol stack configuration La of SMSC1, MTP3 and SCCP are communication functions of the network layer (NW layer), and TCAP, MAP, and SMS applications are communication functions of the application layer (APL layer).

  The protocol stack configuration Lb of the SIGTRAN-GW 40 includes SCTP, M2UA, MTP3, and SCCP. The protocol stack configuration Lc of the MSC 42 includes SCTP, M2UA, MTP3, SCCP, TCAP, and MAP.

  In the order “A”, when a disaster occurs in the area of a certain wireless network 92 (see “disaster occurrence”), the MTC terminal 3 in the wireless network 92 transmits signals such as abnormal notification in a chaotic and large amount. Next, in the order “A”, in the MSC 42 in the carrier networks 90 and 91, the load is increased by the signal from the MTC terminal 3, and a congestion state occurs.

  In order "C", SIGTRAN-GW 40 performs delay measurement on MSC 42 according to SCTP. For example, the SIGTRAN-GW 40 periodically transmits a signal to the MSC 42, and measures the delay by measuring the delay time until the response signal is received from the MSC 42. For example, if the delay time exceeds a predetermined threshold, the SIGTRAN-GW 40 detects the congestion state of the MSC 42 (see “congestion detection”).

  When a congestion state is detected by SCTP, a congestion primitive Pa is output to the upper M2UA. Here, a primitive is a definition of a service that a protocol provides to its upper protocol. In M2UA, congestion detection is notified by the congestion primitive Pa. In M2UA, a congestion primitive Pb is further output to MTP3 on the upper side.

  In MTP3, when congestion detection is notified by the congestion primitive Pb, congestion control is performed. In order “D”, the SIGTRAN-GW 40 transmits a TFC signal to the SMSC 1 each time the signal received from the SMSC 1 is discarded a predetermined number of times (for example, eight times) by congestion control of MTP 3.

  The code | symbol G1 of FIG. 3 shows the example of the parameter of a TFC signal. Note that illustration of unused fields of the TFC signal is omitted.

  The TFC signal includes a congestion level (2 bits), a destination station address (16 bits), a heading code H1 (4 bits), a heading code H2 (4 bits), and a label. In the label, Signaling Link Selection (SLS) (4 bits), Originating station code (OPC: Originating Point Code) (16 bits), and receiving station code (DPC: Destination Point Code) (16 bits) Is included.

  The heading codes H1 and H2 are used to identify the TFC signal. The heading codes H1 and H2 are, for example, “0010” and “0011” (binary numbers), respectively.

  The congestion level indicates the level of congestion in four stages of “0” to “3”. The congestion level "0" indicates that no congestion state has occurred, and the congestion level "3" indicates that the most severe congestion state has occurred. Therefore, the congestion level of the TFC signal is "1" or more.

  The SIGTRAN-GW 40 compares the priority of the signal received from the SMSC 1 with the congestion level, and discards the signal whose priority is lower than the congestion level. Also, the receiving station address indicates the address of the MSC 42 in a congested state. The congestion level and the destination station address are examples of congestion information related to the congestion state.

  Referring back to FIG. 2, when the SMSC 1 receives a TFC signal, it detects congestion by MTP 3. In MTP3, the congestion level and the destination station address are obtained from the TFC signal, and it is determined whether there is a bypass route that can reach the wireless network 92. For example, when there is a bypass route RTa leading to the MSC 42 via another SIGTRAN-GW 40a, switching of the communication route is executed (see "switching").

  If there is no bypass route, the congestion primitive Pc is output from the MTP 3 to the SCCP on the upper side. The congestion primitive and the destination station address are assigned to the congestion primitive Pc. In SCCP, in response to the congestion primitive Pc, the backup node of the congestion state MSC 42 is searched.

  In the order "E", in the SCCP, when there is the presence or absence of a backup node, switching of the communication path is executed (see "switching"). For example, when there is another MSC 42a as a backup node of the MSC 42, the communication path between the SMSC 1 and the IoT-GW 2 can be changed from the path via the SIGTRAN-GW 40 and the MSC 42 by changing the destination from the MSC 42 to the MSC 42a. Switched to a route RTb via the GW 40a and the MSC 42a.

  Also, if neither the bypass route nor the backup node exists, SCCP performs congestion control based on the congestion level. In SCCP congestion control, the priority of the signal transmitted from the SMSC 1 is compared with the congestion level, and the signal whose priority is lower than the congestion level is discarded. For example, when the congestion level is “2”, the signal of priority “1” is discarded without being transmitted.

  Further, in the MTP 3, in response to the reception of the TFC signal, the congestion primitive Pd is output to the SMS application. The congestion primitive and the destination station address are assigned to the congestion primitive Pc.

  In order “F”, the SMS application generates and sends a restriction message (see “Regulation MSG”) according to the congestion primitive Pd. At this time, the priority of the restriction message is set to a value equal to or higher than the congestion level acquired from the TFC signal. For example, when the congestion level is “2”, the priority of the restriction message is set to “3”.

  Therefore, the restriction message is sent without being discarded by the congestion control of SCCP. In addition, since the priority of another SMS message is set to "0", it is discarded by congestion control. Therefore, it is not possible to transmit another SMS message to the MTC terminal 3 in the disaster area until the congestion state of the MSC 42 is cleared.

  The restriction message is processed in each protocol stack configuration La to Lc of the SMSC 1, the SIGTRAN-GW 40, and the MSC 42 and received by the IoT-GW 2 as indicated by a dotted line. As a result, since the MTC terminal 3 of the transmission source of the signal causing the congestion is restricted in signal transmission, the congestion state of the MSC 42 is resolved.

  As described above, when the SMSC 1 receives the TFC signal by the MTP 3, the SMSC 1 generates a congestion primitive Pd from the MTP 3 to the SMS application in addition to the congestion primitive Pc from the MTP 3 to the SCCP. For this reason, in the SMSC 1, in parallel with the search processing and the switching processing of the communication path in the SCCP, the congestion primitive Pd can notify the congestion information of the MSC 42 to the SMS application. Furthermore, since the congestion primitive Pd skips the processing of SCCP, TCAP, and MAP, it is possible to quickly notify congestion information to the SMS application.

  That is, since the SMSC 1 obtains congestion information by the communication function of the network layer and outputs the congestion information to the application layer, the restriction message can be transmitted quickly in the application layer. The congestion primitive Pd is set in advance to the MTP 3 at the time of setting of the first transmission restriction, at the time of activation of the SMSC 1 or by configuration data.

  FIG. 4 is a diagram showing an example of the operation of releasing the regulation of signal transmission. In FIG. 4, the same components as in FIG. 2 will be assigned the same reference numerals and descriptions thereof will be omitted. In addition, "A"-"E" show the order of operation | movement.

  In the order “A”, the SIGTRAN-GW 40 detects the clearing of the congestion state of the MSC 42 as a result of the delay measurement based on SCCP (see “congestion clearing detection”). For example, when the delay time from the transmission of the signal to the reception of the response signal is equal to or less than a predetermined threshold, the SIGTRAN-GW 40 detects the elimination of the congestion state.

  In SCTP, the congestion primitive Pq is notified of M2UA by congestion primitive Pq. The congestion primitive Pq includes a congestion level "0". In M2UA, clearing of the congestion state is notified to MTP3 by the congestion primitive Pr. Thereby, congestion control by MTP3 stops.

  In the order “B”, the SMSC 1 transmits the RCT signal to the SIGTRAN-GW 40 periodically, for example, a predetermined number of times according to the MTP 3.

  The code G2 in FIG. 3 shows an example of the parameters of the RCT signal. Note that illustration of unused fields of the RCT signal is omitted.

  The RCT signal includes a heading code H1 (4 bits), a heading code H2 (4 bits), a label, SIO (service information octet) (8 bits), and PRI (priority) (2 bits). The labels include SLS (4 bits), OPC (16 bits), and DPC (16 bits).

  The heading codes H1 and H2 are used to identify the RCT signal. The heading codes H1 and H2 are, for example, "0001" and "0011" (binary numbers), respectively.

  Also, the priority is expressed in four stages of "0" to "3". Referring again to FIG. 4, the priority is set to a value that is one lower than the congestion level at the time of occurrence of the congestion state of the MSC 42. For example, when the congestion level at the time of occurrence of the congestion state is “1”, the priority is set to “0”.

  Therefore, if the congestion state of the MSC 42 continues, the RCT signal is discarded by MTP 3 congestion control of the SIGTRAN-GW 40, and a TFC signal is transmitted to the SMSC 1 each time a predetermined number of RCT signals are discarded. On the other hand, when the congestion state of the MSC 42 is cleared, the RCT signal is not discarded. In order "C", the RCT signal is forwarded to the MSC 42 and discarded at the MSC 42.

  Therefore, if the SMSC 1 does not receive the TFC signal within a predetermined time from the transmission of the RCT signal in the MTP 3, the SMSC 1 detects the elimination of the congestion state. The MTP 3 manages the congestion level of the MSC 42, and the congestion level is updated according to the congestion level included in the TFC signal. In the above case, the congestion level is updated to "0". Therefore, congestion control in SCCP stops.

  Also, in the order “D”, the congestion primitive Ps is output from the MTP 3 to the SMS application. In the SMS application, a deregulation message is sent according to the congestion primitive Ps.

  The deregulation message is processed in each of the protocol stack configurations La to Lc of the SMSC 1, the SIGTRAN-GW 40, and the MSC 42 and received by the IoT-GW 2 as indicated by a dotted line. As a result, the restriction on the signal transmission is canceled in the MTC terminal 3 that is the transmission source of the signal that causes the congestion, so that the MTC terminal 3 can transmit the signal again.

  Next, the configuration of the SMSC 1 will be described.

  FIG. 5 is a block diagram showing an example of the SMSC 1. The SMSC 1 includes a central processing unit (CPU) 10, a read only memory (ROM) 11, a random access memory (RAM) 12, a hard disk drive (HDD) 13, and a communication port 14. The CPU 10 is connected to the ROM 11, the RAM 12, the HDD 13, and the communication port 14 via a bus 19 so that signals can be input to and output from each other. The CPU 10 is an example of a computer.

  The ROM 11 stores a program for driving the CPU 10. The program includes an operating system (OS) and a congestion control program that executes a congestion control method. The RAM 12 functions as a working memory of the CPU 10. The plurality of communication ports 14 are circuits such as a LAN (Local Area Network) switch, for example, and process communication between the CPU 10 and other devices.

  When the CPU 10 reads a program from the ROM 11, it functions as an SMS control unit 100, a primitive control unit 101, a transmission management unit 102, a position information management unit 103, a number resolution unit 104, a MAP / TCAP control unit 105, and an SCCP control unit 106. , And the MTP control unit 107 are formed. Further, the HDD 13 stores a message database (MSG-DB) 130 and a position information database (DB) 131.

  The primitive control unit 101, the MAP / TCAP control unit 105, the SCCP control unit 106, and the MTP control unit 107 are an example of a first function unit, and execute the communication function of the network layer. The SMS control unit 100, the transmission management unit 102, the position information management unit 103, and the number resolution unit 104 are an example of a second function unit, and execute the communication function of the application layer. That is, the CPU 10 has a communication function of the network layer and a communication function of the application layer. The details of the functions of each part will be described below.

  The SMS control unit 100 executes the function of the SMS application described above. The SMS control unit 100 executes primitive reception registration for enabling reception of the congestion primitive Pd from the SCS 5 via the communication port 14 to the primitive control unit 101.

  FIG. 6 is a diagram illustrating an example of an MTP service primitive. An MTP service primitive is a primitive that can be output from MTP3 to its upper protocol. The primitives include "MTP-Transfer", "MTP-Pause", "MTP-Resume", and "MTP-State Indication". Among these, “MTP-state indication” corresponds to the congestion primitive Pd.

  The parameters of “MTP-transfer” include OPC, DPC, SI (Service Indicator), and user data. The parameters of "MTP-dormant" include DPCs that become unusable. Also, the parameters of “MTP-resume” include DPCs that can be used. The parameters of “MTP-status indication”, ie, congestion primitive Pd, include congestion DPC and congestion level. The congestion DPC corresponds to the destination station address of the TFC signal.

  The SMS control unit 100 uses only “MTP-state display” among the above primitives. In each primitive, an SI value indicating a pointing destination is specified. Since the SI value of “MTP-transfer” does not correspond to SCCP, the SMS control unit 100 is not notified. In addition, since “MTP-pause” and “MTP-resume” for notifying the opposite node failure and recovery, respectively, are notifications common to all the SI values, the SMS control unit 100 performs mask processing. The SMS control unit 100 uses an unused SI value when setting the “MTP-state display” primitive.

  Referring back to FIG. 5, the SMS control unit 100 receives the setting of the restriction form for each IoT-GW 2, that is, for each wireless network 92 via the communication port 14 from the SCS 5. The regulation form defines how to regulate the signal transmission of the MTC terminal 3 (for example, the regulation period is limited to one day). The SMS control unit 100 sets the content of the restriction message to be transmitted to the IoT-GW 2 in the MSG-DB 130 for each IoT-GW 2.

  FIG. 7 is a diagram showing an example of setting of the MSG-DB 130. As shown in FIG. A message ID, an MSISDN (mobile phone number), movement presence / absence information, an MSC address, an MTC pattern ID, and an operation pattern ID are set in the MSG-DB 130.

  The message ID is an identifier of the regulation message for each IoT-GW 2, that is, the wireless network 92. The MSISDN is an example of identification information of the IoT-GW2. The movement presence / absence information indicates whether the IoT-GW 2 is a mobile (for example, a mobile gateway device). When the movement state is “presence (1)”, the IoT-GW 2 is a moving body, and when the movement state is “no (0)”, the IoT-GW 2 is not a movement body.

  The MSC address is the address of the MSC 42 that accommodates the IoT-GW 2. The MSC address is registered only when the IoT-GW 2 is not a mobile (movement presence / absence information = none).

  The MTC pattern ID is an identifier of a pattern of a combination of IDs of MTC terminals 3 that are subject to the control of signal transmission (control target MTC-IDs) among the MTC terminals 3 in the wireless network 92 corresponding to the IoT-GW2. For example, when the MTC pattern ID is # 1, the MTC terminals 3 to be restricted become all the MTC terminals 3. Further, when the MTC pattern ID is # 2, each MTC terminal 3 whose regulation target MTC-ID is MTC01, MTC02, MTC03,. In addition, when the MTC pattern ID is # 3, the MTC terminals 3 whose regulation target MTC-IDs are MTC01, MTC03, MTC05,.

  The operation pattern ID is an identifier of the pattern of the restricted operation of signal transmission. That is, the operation pattern ID is an identifier of a restriction form. For example, when the operation pattern ID is # 1, the operation content is a restriction on signal transmission excluding emergency information. When the operation pattern ID is # 2, the operation content is a restriction that limits the period to one day.

  Note that although a restriction message is set for each IoT-GW 2 in the MSG-DB 130 of this example, a restriction message is set for each MTC terminal 3 for the MTC terminal 3 to which the MSISDN is assigned. The MTC pattern ID is not set for the restriction message of the MTC terminal 3.

  The MTP control unit 107 has a signal processing function of MTP 3 of the protocol stack configuration. The MTP control unit 107 receives the TFC signal via the communication port 14. At this time, the MTP control unit 107 identifies the TFC signal by the heading codes H1 and H2. The MTP control unit 107 acquires congestion information (congestion level and destination station address) from the TFC signal, and outputs the congestion information to the primitive control unit 101.

  Since the MTP control unit 107 acquires congestion information based on the SIGTRAN protocol, it can flexibly adapt to an SMS application based on SS7 signaling.

  The primitive control unit 101 generates a congestion primitive Pd of “MTP-state display” from the congestion information and outputs the congestion primitive Pd to the SMS control unit 100. The SMS control unit 100 specifies the MSC 42 in a congestion state from the destination station address of the congestion information.

  The position information management unit 103 accesses the HLR / HSS 44 and the VLR 45 via the communication port 14. The position information management unit 103 manages the position information of the IoT-GW 2 and the MTC terminal 3 by acquiring the in-zone information of the communication device accommodated in each MSC 42 from the HLR / HSS 44 and the VLR 45. The position information management unit 103 stores the position information in the position information DB 131, and acquires the position information from the position information DB 131 in response to a request from the SMS control unit 100 and the transmission management unit 102.

  The location information is information indicating the IIS-GW 2 accommodated in each MSC 42 and the MSISDN of the MTC terminal 3, and is used to specify the IoT-GW 2 and MTC terminal 3 accommodated in the MSC 42 in a congested state using the receiving station address as a key. Be The location information management unit 103 updates the location information DB 131 every time the location information of the IoT-GW 2 or the MTC terminal 3 changes. Therefore, the latest positions of the IoT-GW 2 and the MTC terminal 3 are stored in the position information DB 131 as the address of the accommodation destination MSC 42.

  The SMS control unit 100 searches the position information DB 131 using the receiving station address as a key, and thereby acquires the I-ISN-GW 2 and the MSISDN of the MTC terminal 3 accommodated in the MSC 42 in a congested state. That is, the SMS control unit 100 acquires the MSISDN from the in-zone information of the communication device accommodated in the MSC 42 in a congested state. Next, the SMS control unit 100 selects the parameter of the restriction message corresponding to the MSISDN by searching the MSG-DB 130 using the MSISDN as a key.

  Thereby, the SMS control unit 100 selects the restriction form for each IoT-GW 2 or MTC terminal based on the MSISDN. Therefore, even if the IoT-GW 2 and the MTC terminal 3 are mobile communication devices, it is possible to regulate signal transmission in an arbitrary restriction form for each IoT-GW 2 or MTC terminal.

  At this time, since the SMS control unit 100 uses MSISDN, that is, a mobile phone number as identification information of the IoT-GW 2 or the MTC terminal 3, it is possible to select the regulation form by using the function of the SMS application using the mobile phone number as a key. It becomes.

  When the mobile communication device is not accommodated in the MSC 42 in a congested state, the SMS control unit 100 may search the MSG-DB 130 using the destination station address as a key without using the location information DB 131. Since the MSC address is set in the MSG-DB 130, the SMS control unit 100 can select the parameters of all restriction messages of the MSC address matching the destination station address.

  Next, the SMS control unit 100 outputs a message transmission request to the transmission management unit 102 based on the parameter of the restriction message selected from the MSG-DB 130. The transmission management unit 102 generates a restriction message in response to the message transmission request.

  FIG. 8 shows an example of the parameter of the message transmission request. The message transmission request includes the MSISDN, the movement presence / absence information, the MSC address, the priority, and the control pattern. The MSISDN, the movement presence / absence information, and the MSC address are acquired from the MSG-DB 130, and the MTC pattern ID and the operation pattern ID included in the control pattern are also acquired from the MSG-DB 130. The MTC pattern and the operation pattern are configured as text or binary code that is the text of the SMS message.

  Also, the priority is determined from the congestion level of the congestion information. The SMS control unit 100 determines a value equal to or higher than the congestion level as the priority. As described above, since the SMS control unit 100 sets in accordance with the congestion level indicated by the congestion information, discarding of the restriction message by MTP congestion control is avoided.

  When the transmission management unit 102 generates the restriction message, the transmission management unit 102 requests the number resolution processing to the number resolution unit 104 based on the MSISDN of the restriction message. The number resolution request includes the parameters of the message transmission request.

  In response to the number resolution request, the number resolution unit 104 determines, based on a predetermined database, whether the MSISDN is that of the IoT-GW 2 or the MTC terminal 3 currently connected to the carrier networks 90, 91. When the MSISDN is not that of the IoT-GW 2 or MTC terminal 3 currently connected to the carrier networks 90 and 91, the number resolution unit 104 notifies the transmission management unit 102 to that effect, and the transmission management unit 102 discards the restriction message. Do.

  When the MSISDN is that of the IoT-GW 2 or the MTC terminal 3 currently connected to the carrier networks 90 and 91, the number resolution unit 104 transmits the HLR / HRS message when the movement presence / absence information in the parameter of the message transmission request indicates “presence”. By accessing the HSS 44 and the VLR 45, the location information of the IoT-GW 2 or the MTC terminal 3 is retrieved. The number resolution unit 104 determines whether the MSC 42 in a congestion state accommodates the IoT-GW 2 or the MTC terminal 3 based on the location information, and notifies the SMS control unit 100 of the determination result.

  When the MSC 42 in the congestion state does not accommodate the IoT-GW 2 or the MTC terminal 3, the SMS control unit 100 discards the restriction message, and when the MSC 42 in the congestion state contains the IoT-GW 2 or the MTC terminal 3, The restriction message is output to the MAP / TCAP control unit 105. Furthermore, when the movement resolution information in the parameter of the message transmission request indicates “absent”, the number resolution unit 104 does not search for the location information, and the SMS control unit 100 uses the restriction message as the MAP / TCAP control unit 105. Output to

  The MAP / TCAP control unit 105 processes the restriction message based on the corresponding protocol, and outputs the process to the SCCP control unit 106. The SCCP control unit 106 performs congestion control on the restriction message based on the congestion level indicated by the congestion information. However, since the priority of the restriction message is set to the congestion level or more, the control message is output to the MTP control unit 107. The MTP control unit 107 outputs the restriction message to the destination indicated by MSISDN via the communication port 14. Thereby, the restriction message is transmitted to the IoT-GW 2 and the MTC terminal 3 accommodated in the MSC 42 in a congested state.

  Further, the MTP control unit 107 periodically transmits, for example, an RCT signal to the SIGTRAN-GW 40 via the communication port 14. At this time, the MTP control unit 107 sets, in the RCT signal, a priority according to the congestion level indicated by the congestion information. For example, the MTP control unit 107 sets, in the RCT signal, a priority that is smaller by one than the congestion level.

  When the MTP control unit 107 does not receive a TFC signal, which is a response signal to the RCT signal, from the SIGTRAN-GW 40 within a predetermined period, the MTP control unit 107 detects that the congestion state of the MSC 42 is cleared by the congestion primitive Ps. Ask to The primitive control unit 101 generates a congestion primitive Ps in response to the request and outputs the congestion primitive Ps to the SMS control unit 100.

  In response to the congestion primitive Ps, the SMS control unit 100 outputs, to the transmission management unit 102, a message transmission request for a restriction release message for releasing the restriction on the signal transmission of the MTC terminal 3. The restriction release message is transmitted from the communication port 14 in the same process as the restriction message.

  Next, the configuration of the IoT-GW 2 will be described.

  FIG. 9 is a block diagram showing an example of the IoT-GW 2. The IoT-GW 2 includes a CPU 20, a ROM 21, a RAM 22, a wired communication interface unit (wired communication IF) 24, and a wireless communication interface unit (wireless communication IF) 25. The CPU 20 is connected to the ROM 21, the RAM 22, the wired communication IF 24, and the wireless communication IF 25 via a bus 29 so that signals can be input to and output from each other.

  The ROM 21 stores a program for driving the CPU 20. The RAM 22 functions as a working memory of the CPU 20. The wired communication IF 24 is configured of a circuit such as a LAN switch, for example, and handles communication between the CPU 10 and another device that performs wired communication with the IoT-GW 2. The wireless communication IF 25 is configured of hardware such as a wireless LAN card, for example, and processes communication between the CPU 10 and another device wirelessly communicating with the IoT-GW 2.

  When the CPU 20 reads a program from the ROM 21, an SMS control unit 200, a message determination unit 201, a position detection unit 202, and an access control unit 203 are formed as functions. The access control unit 203 communicates with the MSC 42 and the MTC terminal 3 via the wired communication IF 24 or the wireless communication IF 25. The SMS control unit 200 processes an SMS message. The message determination unit 201 determines whether the SMS message is a restriction message or a restriction release message. The position detection unit 202 detects the position of the IoT-GW 2 from the communication with the MSC 42 and notifies the HLR / HSS 44 and the VLR 45 of the detected position.

  When the SMS control unit 200 receives an SMS message via the access control unit 203, the SMS control unit 200 outputs the SMS message to the message determination unit 201. When the message determination unit 201 determines that the SMS message is a restriction message or a restriction release message, the message determination unit 201 notifies the SMS control unit 200 of the determination result. When the SMS message is a restriction message, the SMS control unit 200 restricts transmission of a signal to the connected MTC terminal 3 in accordance with the restriction message.

  More specifically, the SMS control unit 200 instructs the MTC terminal 3 corresponding to the MTC pattern ID of the restriction message to perform restriction in a restriction form according to the operation pattern ID of the restriction message. The restriction instruction is transmitted from the wireless communication IF 25 to the MTC terminal 3.

  Furthermore, when the SMS message is a restriction release message, the SMS control unit 200 transmits a restriction release instruction to the MTC terminal 3 that is under control of signal transmission. The instruction for releasing the restriction is transmitted from the wireless communication IF 25 to the MTC terminal 3.

  Next, the configuration of the MTC terminal 3 will be described.

  FIG. 10 is a block diagram showing an example of the MTC terminal 3. The MTC terminal 3 has a CPU 30, a ROM 31, a RAM 32, and a wireless communication interface unit (wireless communication IF) 35. The CPU 30 is connected to the ROM 31, the RAM 32, and the wireless communication IF 35 via a bus 39 so that signals can be input to and output from each other.

  The ROM 31 stores a program for driving the CPU 30. The RAM 32 functions as a working memory of the CPU 30. The wireless communication IF 35 is configured of hardware such as a wireless LAN card, for example, and processes communication between the CPU 30 and another device wirelessly communicating with the MTC terminal 3. When the MTC terminal 3 is accommodated directly in the MSC 42 without passing through the IoT-GW 2, an interface for wired communication may be provided in place of the wireless communication IF 35 depending on the type of communication service.

  When the CPU 30 reads a program from the ROM 31, the communication control unit 300 and the access control unit 301 are formed as functions. The access control unit 301 communicates with the IoT-GW 2 via the wireless communication IF 35. The communication control unit 300 regulates transmission of a signal from the access control unit 301 in accordance with a regulation instruction received from the IoT-GW 2 via the wireless communication IF 25.

  A restriction form in accordance with the operation pattern ID is designated for the restriction instruction, and the communication control unit 300 performs restriction according to the restriction form. For example, in the restriction form, when it is specified that restriction is restricted to one day, the communication control unit 300 performs restriction until one day elapses from the reception of the restriction instruction using a calendar function or the like. In addition, in the control mode, when it is specified that the emergency information is to be removed, the communication control unit 300 performs control so that only the emergency information is transmitted. When the communication control unit 300 receives a restriction release instruction, the communication control unit 300 stops the restriction of the transmission of the signal to the access control unit 301.

  When the MTC terminal 3 is accommodated directly in the MSC 42 without the intervention of the IoT-GW 2, the CPU 30 is formed with the same function as the position detection unit 202 of the IoT-GW 2. Thereby, the MTC terminal 3 detects the position of the MTC terminal 3 from the communication with the MSC 42 and notifies the HLR / HSS 44 and the VLR 45 of the position.

  Next, each process of SMSC 1 will be described.

  FIG. 11 is a flowchart showing an example of the initial setting process. This process is performed, for example, at the time of activation of the SMSC 1, but is not limited thereto, and may be performed during subsequent operation.

  The SMS control unit 100 sets acceptance registration of congestion primitives Pd and Ps of “MTP-state display” to the primitive control unit 101 (step St1). As a result, in response to the reception of the TFC signal, the congestion primitive Pd is output from the primitive control unit 101 that is the communication function of the network layer to the SMS control unit 100 that is the communication function of the application layer. In addition, in response to the fact that the TFC signal, which is the response signal of the RCT signal, has not been received, the congestion primitive Ps is output from the primitive control unit 101 to the SMS control unit 100.

  Next, the SMS control unit 100 determines whether the setting of the transmission restriction is input from the SCS 5 through the communication port 14 (step St2). The SMS control unit 100 ends the processing when there is no input of the setting of the transmission restriction (No in step St2).

  When the SMS control unit 100 receives an input of setting of transmission restriction (Yes in step St2), the SMS control unit 100 sets the MSG-DB 130 according to the input from the SCS 5 (step St3). Thereby, the SMS control unit 100 receives the setting of the restriction form in association with each IoT-GW 2 or the MSISDN of each MTC terminal 3. The setting process of the MSG-DB 130 may be executed by the SMS application or may be executed by another application.

  Next, the position information management unit 103 starts acquisition of location information from the HLR / HSS 44 and the VLR 45 via the communication port 14 (step St4). The position information management unit 103 updates the position information DB 131 based on the location information. In this way, initialization is performed.

  FIG. 12 is a flowchart showing an example of the regulation message transmission process. This process is performed, for example, periodically. In the present process, each process of steps St11-14, St22 and St23 is executed by the communication function of the network layer of CPU 10, and each process of steps St15-21 is executed by the communication function of the application layer of CPU10. . Further, in this process, it is assumed that there is no alternate route or backup node for the MSC 42 in a congested state.

  The MTP control unit 107 determines the presence or absence of reception of the TFC signal from the SIGTRAN-GW 40 (step St11). When the TFC signal is not received (No in step St11), the MTP control unit 107 determines that there is no MSC 42 in a congested state, and ends the process.

  When the TFC signal is received (Yes in step St11), the MTP control unit 107 acquires congestion information, that is, a receiving station address and a congestion level from the TFC signal (step St12). Next, the SCCP control unit 106 starts congestion control based on the congestion state (step St13). More specifically, the SCCP control unit 106 starts congestion control in response to the congestion primitive Pc from the MTP control unit 107.

  Next, the primitive control unit 101 outputs the congestion primitive Pd set in advance to the SMS application (Step St14). That is, the primitive control unit 101 outputs the congestion primitive Pd to the SMS control unit 100. Thus, the SMS control unit 100 is notified of congestion information. The process of step St14 may be performed prior to the process of step St13.

  The SMS control unit 100 identifies the MSC 42 in the congestion state based on the destination station address among the congestion information, and searches the position information DB 131 for the corresponding MSISDN according to the MSC 42 (step St15). Thereby, the SMS control unit 100 acquires the I-IS-GW 2 and the MSISDN of the MTC terminal 3 accommodated in the MSC 42 in a congested state. The SMS control unit 100 can omit this process when the IoT-GW 2 and the MTC terminal 3 accommodated in the MSC 42 in a congested state are not mobile.

  Next, the SMS control unit 100 searches for a parameter of the corresponding restriction message from the MSG-DB 130 based on the MSISDN (Step St16). More specifically, the SMS control unit 100 acquires, from the MSG-DB 130, the parameter of the restriction message to which the MSISDN matches. Thereby, the SMS control unit 100 selects the restriction form for each of the IoT-GW 2 or the MTC terminal 3 based on the MSISDN.

  Thus, even if the IoT-GW 2 or the MTC terminal 3 is a mobile unit, the SMSC 1 obtains the MSISDN from the location information DB 131 based on the area information, and any restriction form for each IoT-GW 2 or MTC terminal 3 Can be used to regulate signal transmission. When the IoT-GW 2 is not a mobile, the SMS control unit 100 may acquire the MSISDN from the MSG-DB 130 based on the receiving station address.

  Next, the SMS control unit 100 sets the priority of the restriction message from the congestion level (step St17). The SMS control unit 100 prevents the discarding of the restriction message by the congestion control of the SCCP control unit 106 by setting the priority of the restriction message according to the congestion level.

  Next, the number resolution unit 104 performs number resolution processing of MSISDN based on the area information (step St18). More specifically, the number resolution unit 104 determines the MSC 42 as the accommodation destination of the IoT-GW 2 or the MTC terminal 3 from the MSISDN.

  Next, the number resolution unit 104 determines the presence / absence of movement (whether mobile or not) of the IoT-GW 2 or MTC terminal 3 corresponding to the MSISDN from movement presence / absence information among the parameters of the restriction message (Step St19). . When there is no movement (No in step St19), the process in step St21 is executed.

  When there is movement (Yes in step St19), the number resolution unit 104 determines whether or not the MSC 42 accommodating the IoT-GW 2 or the MTC terminal 3 matches the MSC 42 in a congested state (step St20). If the MSCs 42 do not match (No in step St20), the process ends. If the MSCs 42 match (Yes in step St20), the SMS control unit 100 outputs a message transmission request to the transmission management unit 102 (step St21). The transmission management unit 102 outputs the restriction message to the network layer.

  Next, the SCCP control unit 106 compares the priority of the restriction message with the congestion level (step St22). However, since the priority of the restriction message is set to the congestion level or more by the SMS control unit 100, the restriction message is not discarded. Next, the MTP control unit 107 transmits the restriction message from the communication port 14 to the IoT-GW 2 or the MTC terminal 3 (Step St23). In this way, the restriction message transmission process is performed.

  As described above, the SMS control unit 100 receives, for each wireless network 92 or each MTC terminal 3, the setting of the restriction form of transmission of the signal of the MTC terminal 3. Further, the MTP control unit 107 acquires congestion information, and the primitive control unit 101 outputs the congestion information to the SMS control unit 100 as a congestion primitive Pd. The SMS control unit 100 selects a restriction form based on the congestion information, and transmits a restriction message to the wireless network 92 according to the selected restriction form.

  According to the above configuration, the SMS control unit 100 can immediately obtain congestion information regardless of the process of the network layer, so that the restriction message can be transmitted quickly. In addition, since the SMS control unit 100 selects the restriction form for each of the wireless network 92 or the MTC terminal 3, the SMS control part 100 can restrict signal transmission in an arbitrary restriction form.

  Therefore, the SMSC 1 can quickly regulate congestion-causing signaling in any form.

  FIG. 13 is a flowchart illustrating an example of the process of transmitting the restriction release message. In this process, steps St31 to St38 are executed by the communication function of the network layer, and steps St38b and St39 are executed by the communication function of the application layer.

  The MTP control unit 107 determines whether the transmission cycle of the RCT signal has arrived, for example, by the timer (step St31). If the transmission cycle has not arrived (No in step St31), the MTP control unit 107 ends the process. Further, when the transmission cycle has arrived (Yes in Operation St31), the MTP control unit 107 generates an RCT signal (Operation St32).

  Next, the MTP control unit 107 sets the priority of the RCT signal from the congestion level (step St33). The MTP control unit 107 sets, for example, the priority to a value smaller than the congestion level by one so that the RCT signal is discarded when the congestion state of the MSC 42 is not cleared. Next, the MTP control unit 107 transmits an RCT signal (Step St34), and activates the monitoring timer (Step St34a). The monitoring timer is used to monitor the presence or absence of reception of a response signal (TFC signal) to the RCT signal from the SIGTRAN-GW 40.

  Next, the MTP control unit 107 determines whether the monitoring timer has expired (step St35). When the monitoring timer has not expired (No in Operation St35), the MTP control unit 107 determines whether or not the TFC signal has been received (Operation St36). Here, when the congestion state of the MSC 42 continues, the SIGTRAN-GW 40 discards the RCT signal a predetermined number of times, and then transmits a TFC signal as a response signal to the SMSC 1. When the TFC signal is not received (No in Operation St36), the MTP control unit 107 executes the processing in Operation St35 again. Further, when the TFC signal is received (Yes in Operation St36), the MTP control unit 107 ends the processing. The RCT signal is an example of a test signal.

  When the monitoring timer has expired (Yes in step St35), the MTP control unit 107 determines that the TFC signal is not received, and causes the SCCP control unit 106 to stop congestion control (step St37). Here, when the congestion state of the MSC 42 is resolved, the SIGTRAN-GW 40 does not transmit the TFC signal because it transfers the RCT signal without discarding it in order to set the congestion level to zero. Therefore, the MTP control unit 107 determines that the congestion state has been eliminated and sets the congestion level to 0 when the TFC signal is not received before the monitoring timer expires.

  Next, the MTP control unit 107 stops the timer that counts the transmission cycle of the RCT signal (step St38). Next, the primitive control unit 101 outputs the congestion primitive Ps to the application layer in order to notify that the congestion level is 0 (Step St38a). The congestion primitive Ps includes the address of the MSC 42 whose congestion state has been eliminated.

  The SMS control unit 100 searches the position information DB 131 for the corresponding MSISDN based on the address of the MSC 42 (Step St38 b). As a result, the SMS control unit 100 acquires the MSISDN of the IoT-GW 2 and the MTC terminal 3 to be deregulated. Next, the SMS control unit 100 outputs a message transmission request for a restriction release message to the transmission management unit 102 (step St39). The transmission management unit 102 outputs the restriction release message to the network layer.

  Next, the MTP control unit 107 transmits the restriction release message to the IoT-GW 2 or the MTC terminal 3 (Operation St40). Thus, the process of transmitting the restriction release message is performed.

  As described above, the MTP control unit 107 transmits, to the SIGTRAN-GW 40 which is a node from which congestion information is acquired, an RCT signal with a priority according to the congestion level indicated by the congestion information. Further, when the primitive control unit 101 does not receive a TFC signal as a response signal to the RCT signal from the SIGTRAN-GW 40, the primitive control unit 101 outputs the congestion primitive Ps to the SMS control unit 100 as a notification of clearing the congestion state. The SMS control unit 100 transmits a restriction release message to the wireless network 92 in accordance with the congestion primitive Ps.

  Therefore, the SMSC 1 can detect the cancellation of the congestion state and release the restriction on the signal transmission of the MTC terminal 3.

  Next, processing of the IoT-GW 2 will be described.

  FIG. 14 is a flowchart illustrating an example of the reception process of the restriction message and the restriction release message of the IoT-GW 2. This process is performed, for example, periodically.

  The SMS control unit 200 determines whether or not the SMS message from the SMSC 1 has been received (step St51). If the SMS message has not been received (No in step St51), the SMS control unit 200 ends the process. When the SMS control unit 200 receives an SMS message (Yes in step St51), the message determination unit 201 determines whether the SMS message is a restriction message (step St52).

  If the SMS message is a restriction message (Yes in Step St52), the SMS control unit 200 detects the MTC terminal 3 as a restriction target from the MTC pattern ID of the restriction message (Step St53). Next, the SMS control unit 200 detects the restriction form for each of the MTC terminals 3 from the operation pattern ID of the restriction message (Step St54). Next, the SMS control unit 200 transmits a restriction instruction to the corresponding MTC terminal 3 (step St55).

  If the SMS message is not a restriction message (No in step St52), the SMS control unit 200 determines whether the SMS message is a restriction release message (step St56). If the SMS message is a restriction release message (Yes in step St56), the SMS control unit 200 detects the MTC terminal 3 targeted for restriction release from the restriction release message (step St57). Next, the SMS control unit 200 transmits a restriction release instruction to the corresponding MTC terminal 3 (step St58).

  If the SMS message is not a restriction release message (No in step St56), the SMS control unit 200 ends the process. Thus, reception processing of the regulation message and the deregulation message is performed.

  Next, the process of the MTC terminal 3 will be described.

  FIG. 15 is a flowchart showing an example of the process of the transmission restriction and the restriction cancellation of the MTC terminal 3. This process is performed, for example, periodically.

  The communication control unit 300 determines whether a restriction instruction has been received from the IoT-GW 2 (step St 61). When the communication control unit 300 receives the restriction instruction (Yes in Step St61), the communication control unit 300 restricts the signal transmission in the instructed restriction form (Step St62).

  When the communication control unit 300 does not receive the restriction instruction (No in step St61), the communication control unit 300 determines whether the restriction release instruction is received from the IoT-GW 2 (step St63). When the communication control unit 300 receives the restriction release instruction (Yes in step St63), the communication control unit 300 stops the restriction on signal transmission (step St64).

  If the communication control unit 300 has not received the restriction release instruction (No in step St63), the communication control unit 300 ends the process. Thus, the process of the transmission restriction and the restriction cancellation of the MTC terminal 3 is executed. When the MTC terminal 3 is directly accommodated in the MSC 42, the MTC terminal 3 receives the restriction message or the restriction release message, but the process is the same as that of the IoT-GW 2 with the restriction target as the own device. .

  As described above, since SMSC 1 regulates and cancels the signal transmission of MTC terminal 3 by SMS message, high compatibility can be realized by a highly versatile protocol with IoT-GW 2 or MTC terminal 3 it can.

  Further, since the SMSC 1 selects the restriction form for each of the IoT-GW 2 or the MTC terminal 3, the SMSC 1 can restrict signal transmission of the MTC terminal 3 by any method.

  FIG. 16 is a diagram illustrating an example of transmission restriction. In this example, the wireless network 92x of the MTC terminal 3 including the field sensor of the company X, the wireless network 92y of the MTC terminal 3 including the field sensor of the company Y, and the wireless network 92z of the MTC terminal 3 including the field sensor of the company Z Give The wireless network 92y includes the MTC terminals 3 of the group # 1 and the group # 2.

  The wireless networks 92x to 92z are connected to the carrier networks 90 and 91 by IoT-GWs 2x to 2z, respectively. It is assumed that the IoT-GWs 2x to 2z are accommodated in the common MSC 42.

  An MSISDN "020-XXXX-XXXX" is assigned to the IoT-GW 2x. Further, to the IoT-GW 2 y, an MSISDN “020-YYYY-1111” corresponding to the MTC terminal 3 of group # 1 and an MSISDN “020-YYYY-2222” corresponding to the MTC terminal 3 of group # 2 are allocated. ing. Further, to the IoT-GW 2 z, an MSISDN “020-ZZZZ-ZZZZ” is assigned.

  The SMSC 1 regulates signal transmission in an individual regulation form for each MTC terminal 3 based on the MSG-DB 130.

  For example, the SMSC 1 controls the restriction message M1 in which the operation pattern ID “# 1” of the restriction form except emergency information is designated, IoT-GW 2 x, 2 y of MSISDN “020-XXXX-XXXX” and “020-YYYY-1111”. Send to each For this reason, the MTC terminals 3 of the wireless network 92x and the MTC terminals 3 of the group # 1 of the wireless network 92y are restricted in signal transmission except for the emergency information.

  Further, the SMSC 1 controls the restriction message M2 in which the operation pattern ID "# 2" of the restriction form which limits the period to one day is designated as an IoT- of the MSISDN "020-ZZZZ-ZZZZ" and "020-YYYY-2222". It transmits to GW2z and 2y respectively. For this reason, the MTC terminals 3 of the wireless network 92z and the MTC terminals 3 of the group # 2 of the wireless network 92y are restricted in signal transmission only for one day.

  Thus, the SMSC 1 can regulate signal transmission in any form of regulation.

  In the above example, the SMSC 1 eliminates the congestion state of the MSC 42 by regulating the signal transmission of the MTC terminal 3, but, for example, it switches the carrier network 90, 91 of the connection destination of the MTC terminal 3 to congestion. You may clear the condition. In this case, the SMSC 1 generates an SMS message instructing switching of the carrier networks 90 and 91 in response to the input from the SCS 5 and transmits the SMS message to the IoT-GW 2 connected to the wireless network 92 of the corresponding MTC terminal 3.

  The IoT-GW 2 switches the connection destination carrier networks 90 and 91 by the SMS control unit 200. More specifically, the SMS control unit 200 switches the accommodation destination of the IoT-GW 2 from the MSC 42 of one carrier network 90, 91 to the MSC 42 of the other carrier network 91, 90. For example, the IoT-GW 2 accommodated in the MSC 42 of one carrier network 90 is switched to the MSC 42 of the other carrier network 91 as indicated by a symbol L.

  Thereby, since the connection destination of the MTC terminal 3 is switched from the MSC 42 of one carrier network 90, 91 to the MSC 42 of the other carrier network 91, 90, the congestion state of the MSC 42 of the original accommodation destination is resolved.

  The above processing functions can be realized by a computer. In that case, a program is provided which describes the processing content of the function that the processing device should have. The above processing functions are realized on the computer by executing the program on the computer. The program in which the processing content is described can be recorded on a computer readable recording medium (except for the carrier wave).

  In the case of distributing the program, for example, the program is sold in the form of a portable recording medium such as a DVD (Digital Versatile Disc), a CD-ROM (Compact Disc Read Only Memory) or the like in which the program is recorded. Alternatively, the program may be stored in the storage device of the server computer, and the program may be transferred from the server computer to another computer via a network.

  The computer executing the program stores, for example, the program recorded on the portable recording medium or the program transferred from the server computer in its own storage device. Then, the computer reads the program from its storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing in accordance with the program. The computer can also execute processing in accordance with the received program each time the program is transferred from the server computer.

  The embodiments described above are examples of preferred implementations of the invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

The following appendices will be further disclosed in connection with the above description.
(Supplementary Note 1) A congestion control method for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks,
A computer having a communication function of a network layer and a communication function of an application layer
A process of acquiring congestion information related to the congestion state by the communication function of the network layer and outputting the congestion information to the application layer;
A process of accepting the setting of the restriction form of transmission of the signal for each of the one or more first networks or each of the plurality of terminals by the communication function of the application layer;
A process of selecting the restriction form based on the congestion information by the communication function of the application layer, and transmitting a message for restricting the transmission of the signal to the one or more first networks according to the selected restriction form; A congestion control method characterized in that it executes.
(Supplementary note 2) The congestion control method according to supplementary note 1, wherein the message is an SMS message.
(Supplementary Note 3) The congestion control method according to Supplementary note 1 or 2, wherein in the process of acquiring the congestion information and outputting the congestion information to the application layer, the congestion information is acquired based on a SIGTRAN protocol.
(Supplementary Note 4) In the process of accepting the setting of the restriction form,
Accepting the setting of the restriction form in association with identification information of each of the one or more gateway devices respectively connecting the one or more first networks and the second network or each of the plurality of terminals;
In the process of transmitting the message to the one or more first networks,
Identifying a switch in a congestion state in the second network from the congestion information;
Acquiring the identification information from the in-zone information of the communication device accommodated in the exchange;
The congestion control method according to any one of appendices 1 to 3, characterized in that the restriction form is selected for each gateway apparatus or each terminal based on the identification information.
(Supplementary Note 5) The congestion control method according to Supplementary note 4, wherein identification information of each of the gateway devices or each of the plurality of terminals is a mobile telephone number.
(Supplementary Note 6) In the process of transmitting the message to the one or more first networks,
The congestion control method according to any one of appendices 1 to 5, wherein the priority of the message is set according to the level of the congestion state indicated by the congestion information.
(Supplementary Note 7) A process of transmitting a test signal with a priority according to the level of the congestion state indicated by the congestion information to the acquisition source node of the congestion information by the communication function of the network layer.
A process of outputting a notification of cancellation of the congestion state to the application layer when the communication function of the network layer does not receive a response signal to the test signal from the acquisition source node;
The computer executes a process of transmitting a message for releasing the restriction on transmission of the signal to the one or more first networks in response to the notification of cancellation of the congestion state by the communication function of the application layer. The congestion control method according to any one of appendices 1 to 6, characterized in that
(Supplementary Note 8) In a congestion control program for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks,
In a computer having a communication function of a network layer and a communication function of an application layer,
The communication function of the network layer acquires congestion information related to the congestion state and outputs the congestion information to the application layer,
The setting of the restriction form of transmission of the signal is accepted for each of the one or more first networks or each of the plurality of terminals by the communication function of the application layer,
The control function of the application layer selects the restriction form based on the congestion information, and transmits a message for restricting transmission of the signal to the one or more first networks according to the selected restriction form. Congestion control program characterized by causing
(Supplementary note 9) The congestion control program according to supplementary note 8, wherein the message is an SMS message.
(Supplementary note 10) The congestion control program according to Supplementary note 8 or 9, characterized in that the congestion information is acquired based on a SIGTRAN protocol in the process of acquiring the congestion information and outputting the congestion information to the application layer.
(Supplementary Note 11) In the process of accepting the setting of the restriction form,
Accepting the setting of the restriction form in association with identification information of each of the one or more gateway devices respectively connecting the one or more first networks and the second network or each of the plurality of terminals;
In the process of transmitting the message to the one or more first networks,
Identifying a switch in a congestion state in the second network from the congestion information;
Acquiring the identification information from the in-zone information of the communication device accommodated in the exchange;
The congestion control program according to any one of appendices 8 to 10, wherein the restriction form is selected for each gateway apparatus or each terminal based on the identification information.
(Supplementary note 12) The congestion control program according to supplementary note 11, wherein identification information of each of the gateway devices or each of the plurality of terminals is a mobile phone number.
(Supplementary Note 13) In the process of transmitting the message to the one or more first networks,
The congestion control program according to any one of appendices 8 to 12, wherein the priority of the message is set according to the level of the congestion state indicated by the congestion information.
(Supplementary Note 14) The communication function of the network layer transmits a test signal having a priority according to the level of the congestion state indicated by the congestion information to the acquisition source node of the congestion information.
When the communication function of the network layer does not receive a response signal to the test signal from the acquisition source node, a notification of cancellation of the congestion state is output to the application layer,
Causing the computer to execute a process of transmitting a message for releasing the restriction on transmission of the signal to the one or more first networks according to the notification of cancellation of the congestion state by the communication function of the application layer The congestion control program according to any one of appendices 8 to 13, characterized in that
(Supplementary Note 15) In a congestion control apparatus that controls a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks,
A first functional unit that executes a communication function of the network layer;
And a second function unit that executes the communication function of the application layer,
The first function unit acquires congestion information on the congestion state and outputs the congestion information to the second function unit.
The second function unit is
Accepting the setting of the restriction form of transmission of the signal for each of the one or more first networks or each of the plurality of terminals;
A congestion control apparatus, comprising: selecting the restriction form based on the congestion information; and transmitting a message for restricting transmission of the signal according to the selected restriction form to the one or more first networks.
(Supplementary note 16) The congestion control device according to supplementary note 15, wherein the message is an SMS message.
(Supplementary note 17) The congestion control device according to supplementary note 15 or 16, wherein the first function unit acquires the congestion information based on a SIGTRAN protocol.
(Supplementary Note 18) The second function unit
Accepting the setting of the restriction form in association with identification information of each of the one or more gateway devices respectively connecting the one or more first networks and the second network or each of the plurality of terminals;
Identifying a switch in a congestion state in the second network from the congestion information;
Acquiring the identification information from the in-zone information of the communication device accommodated in the exchange;
The congestion control device according to any one of appendages 15 to 17, wherein the restriction form is selected for each of the gateway device or the terminal based on the identification information.
(Supplementary Note 19) The first function unit transmits a test signal with a priority according to the level of the congestion state indicated by the congestion information to the acquisition source node of the congestion information, and from the acquisition source node When the response signal to the test signal is not received, a notification of cancellation of the congestion state is output to the second function unit,
The said 1st function part transmits the message which cancels | releases the control of transmission of the said signal to said one or more 1st networks according to the notification of cancellation | release of the said congestion state, The any one of the additional 15 thru | or 18 characterized by the above-mentioned. A congestion control device according to any one of the preceding claims.
(Supplementary Note 20) A congestion control apparatus for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks,
And one or more gateway devices respectively connecting the one or more first networks and the second network;
The congestion control device has a first function unit that executes a communication function of a network layer, and a second function unit that executes a communication function of an application layer,
The first function unit acquires congestion information on the congestion state and outputs the congestion information to the second function unit.
The second function unit is
Accepting the setting of the restriction form of transmission of the signal for each of the one or more first networks or each of the plurality of terminals;
The restriction form is selected based on the congestion information, and a message that restricts transmission of the signal according to the selected restriction form is transmitted to the one or more gateway devices.
The network system, wherein the one or more gateways restrict transmission of the signal to the plurality of terminals according to the message.

1 SMSC
2 IoT-GW
3 MTC terminal 10 CPU
100 SMS control unit 101 Primitive control unit 102 Transmission management unit 103 Position information management unit 104 Number resolution unit 105 MAP / TCAP control unit 106 SCCP control unit 107 MTP control unit 130 MSG-DB
131 location information DB

Claims (10)

A congestion control method for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks,
A computer having a communication function of a network layer and a communication function of an application layer
A process of acquiring congestion information related to the congestion state by the communication function of the network layer and outputting the congestion information to the application layer;
A process of accepting the setting of the restriction form of transmission of the signal for each of the one or more first networks or each of the plurality of terminals by the communication function of the application layer;
A process of selecting the restriction form based on the congestion information by the communication function of the application layer, and transmitting a message for restricting the transmission of the signal to the one or more first networks according to the selected restriction form; A congestion control method characterized in that it executes.   The congestion control method according to claim 1, wherein the message is an SMS message.   3. The congestion control method according to claim 1, wherein in the process of acquiring the congestion information and outputting the congestion information to the application layer, the congestion information is acquired based on a SIGTRAN protocol. In the process of accepting the setting of the restriction form,
Accepting the setting of the restriction form in association with identification information of each of the one or more gateway devices respectively connecting the one or more first networks and the second network or each of the plurality of terminals;
In the process of transmitting the message to the one or more first networks,
Identifying a switch in a congestion state in the second network from the congestion information;
Acquiring the identification information from the in-zone information of the communication device accommodated in the exchange;
The congestion control method according to any one of claims 1 to 3, wherein the restriction form is selected for each gateway apparatus or each terminal based on the identification information.   5. The congestion control method according to claim 4, wherein identification information of each of the gateway devices or each of the plurality of terminals is a mobile telephone number. In the process of transmitting the message to the one or more first networks,
The congestion control method according to any one of claims 1 to 5, wherein the priority of the message is set according to the level of the congestion state indicated by the congestion information. A process of transmitting a test signal with a priority according to the level of the congestion state indicated by the congestion information to the node from which the congestion information is acquired, by the communication function of the network layer;
A process of outputting a notification of cancellation of the congestion state to the application layer when the communication function of the network layer does not receive a response signal to the test signal from the acquisition source node;
The computer executes a process of transmitting a message for releasing the restriction on transmission of the signal to the one or more first networks in response to the notification of cancellation of the congestion state by the communication function of the application layer. The congestion control method according to any one of claims 1 to 6, wherein A congestion control program for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks;
In a computer having a communication function of a network layer and a communication function of an application layer,
The communication function of the network layer acquires congestion information related to the congestion state and outputs the congestion information to the application layer,
The setting of the restriction form of transmission of the signal is accepted for each of the one or more first networks or each of the plurality of terminals by the communication function of the application layer,
The control function of the application layer selects the restriction form based on the congestion information, and transmits a message for restricting transmission of the signal to the one or more first networks according to the selected restriction form. Congestion control program characterized by causing In a congestion control apparatus for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks,
A first functional unit that executes a communication function of the network layer;
And a second function unit that executes the communication function of the application layer,
The first function unit acquires congestion information on the congestion state and outputs the congestion information to the second function unit.
The second function unit is
Accepting the setting of the restriction form of transmission of the signal for each of the one or more first networks or each of the plurality of terminals;
A congestion control apparatus, comprising: selecting the restriction form based on the congestion information; and transmitting a message for restricting transmission of the signal according to the selected restriction form to the one or more first networks. A congestion control device for controlling a congestion state of a second network by signals transmitted from a plurality of terminals in one or more first networks;
And one or more gateway devices respectively connecting the one or more first networks and the second network;
The congestion control device has a first function unit that executes a communication function of a network layer, and a second function unit that executes a communication function of an application layer,
The first function unit acquires congestion information on the congestion state and outputs the congestion information to the second function unit.
The second function unit is
Accepting the setting of the restriction form of transmission of the signal for each of the one or more first networks or each of the plurality of terminals;
The restriction form is selected based on the congestion information, and a message that restricts transmission of the signal according to the selected restriction form is transmitted to the one or more gateway devices.
The network system, wherein the one or more gateways restrict transmission of the signal to the plurality of terminals according to the message.

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