JP6726065B2 - Communication system and paging method - Google Patents

Description

The present invention relates to a gateway device, a call processing node, and a paging method in a mobile communication system that includes a plurality of core networks and in which a mobile communication terminal is distributed to any one of the core networks.

The following Non-Patent Document 1 (particularly sections 4.3.25 and 5.19) describes a dedicated core network (Dedicated Core Network) for a specific application in a mobile communication system. A technique of assigning an acute accent to an e))) and allocating a mobile communication terminal to a Decor according to the feature of the application of the mobile communication terminal is disclosed.

3GPP TS 23.401 V13.7.0 (2016-06)

In a conventional mobile communication system, when a call processing node of a certain core network has failed and downlink communication for the call processing node has occurred, another call processing in the same core network is continued in order to continue the call processing. Paging is performed to bypass the node. In that case, there is a concern that the processing load of the core network will increase and network congestion will occur. For example, when the above-mentioned core network is the Decor, since the Decor is a dedicated core network for a specific application, the surplus equipment is often small from the viewpoint of cost efficiency, and therefore the paging load is small. However, there is a concern that the processing load of the Decor will increase and the congestion of the network will occur.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a gateway device, a call processing node, and a paging method that can reduce the processing load of a failed core network. ..

In order to solve the above problems, a gateway device according to one aspect of the present invention includes a first core network and a second core network different from the first core network, in which one mobile communication terminal is currently accommodated. A gateway device in a mobile communication system including: a fault information storage unit for storing fault information of a second core network; and a second call process for downlink communication when downlink communication to a mobile communication terminal is received. A failure determination unit that determines whether or not a call processing node of the core network has a failure based on the failure information stored in the failure information storage unit, and a failure determination unit that causes a failure in the call processing node If it is determined that the call processing node of the first core network is included as a call processing node candidate for transmitting paging, the call processing node is selected from the call processing node candidates, and paging is performed for the selected call processing node. And a paging transmission unit for transmission.

According to such a gateway device, paging is performed when it is determined that the downlink communication to the mobile communication terminal is received and the call processing node of the second core network that performs the call processing of the downlink communication has a failure. The call processing node of the first core network is included as a call processing node candidate for transmitting the call, the call processing node is selected from the call processing node candidates, and paging is transmitted to the selected call processing node. If such a configuration is adopted, the call processing node of the first core network is also targeted as a paging destination, so the processing load due to paging is distributed to the first core network, and the processing load of the failed second core network is reduced. Can be reduced.

According to the present invention, it is possible to reduce the processing load of a core network in which a failure has occurred.

It is a figure explaining the paging process in a prior art. It is a figure explaining the paging process in the mobile communication system containing the gateway apparatus and call processing node which concern on embodiment of this invention. It is a functional block diagram of the gateway device concerning the embodiment of the present invention. It is a hardware block diagram of the gateway apparatus which concerns on embodiment of this invention. It is a functional block diagram of the call processing node concerning the embodiment of the present invention. It is a hardware block diagram of the call processing node which concerns on embodiment of this invention. It is a sequence diagram (the 1) which shows the paging process (paging method) performed with the mobile communication system containing the gateway apparatus and call processing node which concern on embodiment of this invention. It is a sequence diagram (the 2) which shows the paging process (paging method) performed with the mobile communication system containing the gateway apparatus and call processing node which concern on embodiment of this invention.

Hereinafter, an embodiment of an apparatus according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a diagram illustrating a paging process according to a conventional technique. More specifically, FIG. 1 illustrates paging in the case where a downlink communication for a mobile communication terminal is received when a failure occurs in the core network in which the mobile communication terminal is currently accommodated in the conventional mobile communication system. The flow of processing between each device regarding processing is shown in steps S01a to S10a (described later). As shown in FIG. 1, the mobile communication system 7a includes a UE (User Equipment) 5a, an eNB (evolved Node B) 4a, an MME (Mobility Management Entity) 2a (MME2-1-1a, MME2-2-1a and MME2-). 2-2a and the like are collectively referred to as 2a), an HSS (Home Subscriber Server) 6a, an S-GW (Serving Gateway) 1a, and a P-GW (Packet Data Network Gateway) 3a.

The UE 5a is a mobile communication terminal and performs mobile communication in the mobile communication system 7a. The eNB 4a is a so-called base station, has a radio resource management function, a mobility management function, a radio bearer control function, a scheduling function, and the like, and is connected to a core network to transfer user packets. The MME 2a is a mobility management control device that performs mobility management (bearing control) and bearer control such as setting/releasing a session (connection) for packet communication and controlling handover. The HSS 6a is a subscriber information management device that stores subscriber profile information and the like. The S-GW 1a is a routing gateway device that provides a routing function and a transfer function for user packets. The P-GW 3a is an external network gateway device that plays a role of a connection point with an external network such as an IP service network of a telecommunications carrier or the public Internet, and transfers user packets to and from the external network. In addition, each of the above-mentioned UE5a, eNB4a, MME2a, HSS6a, S-GW1a, and P-GW3a is prescribed|regulated by 3GPP(Third Generation Partnership Project), and has prescribed|regulated functions other than the above-mentioned. I shall. The description of the content defined by 3GPP is omitted in this embodiment. Further, various mobile communication systems described in the present embodiment may include other nodes and functions defined by 3GPP.

The mobile communication system 7a shown in FIG. 1 includes two core networks, a default CN (default core network) 2-1a and a Decor 2-2a, each core network being formed by one or more MMEs 2a. Then, when the UE 5a first attaches to the mobile communication system 7a, the attach request from the UE 5a is transferred to the MME 2a of the default CN 2-1a which is the default core network. In the MME 2a, a core network based on the characteristics of the usage of the UE 5a (terminal usage type identification information described below) is selected (for example, Decor 2-2a is selected), and an attachment process is performed in the selected core network. It This makes it possible to construct a plurality of core networks in the mobile communication system and distribute the mobile communication terminals to the core networks according to the characteristics of the application of the mobile communication terminal. For details of the processing of Decor, refer to “3GPP TS 23.401 V13.7.0 (2016-06)” in Non-Patent Document.

Before describing the flow of the processing in FIG. 1, it is assumed that the UE 5a is attached to the MME2-2-1a of the Decoror 2-2a as an initial state, and the MME2-2-1a has failed. The S-GW 1a regularly monitors the managed MME 2a, and the S-GW 1a detects a failure of the MME 2-2-1a (S01a). Next, the S-GW 1a receives the downlink communication from the P-GW 3a to the UE 5a (S02a). Since the S-GW 1a knows that the MME 2-2-1a to which the UE 5a is attached is out of order, the S-GW 1a causes the MME 2-2-2a, which is another MME in the Decor 2-2a, to operate. Paging (IMSI (International Mobile Subscriber Identity) Paging) is transmitted (S03a). Next, the MME2-2-2a transmits paging to the eNB4a (S04a), and the eNB4a transmits paging to the UE5a (S05a).

Next, the UE 5a transmits an attach to the eNB 4a as a paging response (S06a), and the eNB 4a transmits the attach to the MME 2-1-1a which is the MME of the default CN 2-1a which is the default core network ( S07a). Next, the MME 2-1-1a sends an inquiry about the terminal use type identification information to the HSS 6a (S08a), and in response, the HSS 6a sends the terminal use type identification information to the MME 2-1-1a (S09a). ). Next, the MME 2-1-1a determines that the UE 5a should be accommodated in the Decor 2-2a based on the received terminal usage type identification information, and the MME 2-1-1a attaches the MME of the Decor 2-2a. Is redirected to MME2-2-2a (S10a).

There are two problems as the problems of the paging process in the above-described conventional technique. The first problem is that in S03a, paging is transmitted to the MME2-2-2a, which is another MME in the Decor2-2a including the MME2-2-1a that is in failure, and thus the Decor2-2a That is, the paging processing load is increased in the MME 2a, and the possibility of network congestion in the Decor 2-2a is increased. The second problem is that in S10a, the attach is redirected to the MME2-2-2a of the Decor2-2a, so that the load of the attaching process of the return in the MME2a of the Decor2-2a becomes large, and the attach is performed in the Decor2-2a. Network congestion is more likely to occur. In order to solve the above-mentioned two problems, it is conceivable to add the equipment (MME 2a etc.) of the Decor 2-2a. However, since Decor is a technology that realizes cost efficiency by constructing a core network for a specific purpose in the first place, it is inevitable to add equipment. In addition, existing load balancing technologies such as S1-Flex, which is an existing technology, are premised on the same core network and cannot be applied to Decor.

FIG. 2 is a diagram illustrating a paging process in the mobile communication system 7 including the S-GW 1 (gateway device) and the MME 2 (call processing node) according to the embodiment of the present invention. Each node and each process in FIG. 1 and each node and each process in FIG. 2 which is a name excluding the last “a” of the name have almost the same configuration or process, and detailed description thereof will be omitted. Only the difference will be described. After S02, when the S-GW1 determines that it is the MME2-2-1 that is in failure to perform the call processing of the downlink communication received in S02, the S-GW1 differs from the Decor2-2 (second core network). The MME 2 of the default CN 2-1 (first core network) which is the core network is added as a paging destination candidate. Then, when the MME 2-1-1 of the default CN 2-1 is selected as the paging destination from the destination candidates, the S-GW 1 transmits the paging to the selected MME 2-1-1 (S03b). It should be noted that the paging transmitted in S03b includes faulty node information related to the malfunctioning MME 2-2-1, and the MME 2-1-1 receiving the paging transmits the faulty node information included in the paging. Hold.

After S09, the MME 2-1-1 holds whether or not the attach from the UE 5 (mobile communication terminal, one mobile communication terminal) is for the MME 2 of the Decor 2-2. Determine based on faulty node information. Then, if the MME2 of the Decor 2-2 is targeted, the MME 2-1-1 does not redirect to the MME 2 of the Decor 2-2a, and executes the process as an attachment to the Decor 2-2.

The mobile communication system 7 shown in FIG. 2 can solve the above two problems. Specifically, as for the first problem, as in S03b, paging is less likely to be transmitted to the MME2 of the Decor 2-2, and thus the load of the paging process is reduced in the MME 2 of the Decor 2-2. As for the second problem, as in the processing after S09, the attachment is less likely to be redirected to the MME2 of the Decoror 2-2, so that the load of the return attachment processing is reduced in the MME2 of the Decoror 2-2.

The mobile communication system 7 may include one or more S-GW1, MME2, P-GW3, eNB4, UE5, and HSS6, respectively, or may not include some of them.

The difference between the paging process in the related art and the paging process in the mobile communication system 7 including the S-GW 1 and the MME 2 according to the embodiment of the present invention has been described above with reference to FIGS. 1 and 2. The functions of the S-GW1 and MME2 will be described below.

FIG. 3 is a functional block diagram of the S-GW1. As shown in FIG. 3, the S-GW 1 includes a failure monitoring unit 10, a failure information storage unit 11, a downlink communication reception unit 12, a failure determination unit 13, and a paging transmission unit 14.

The functional block diagram shown in FIG. 3 shows functional blocks. These functional blocks (components) are realized by an arbitrary combination of hardware and/or software. Further, the means for realizing each functional block is not particularly limited. That is, each functional block may be implemented by one device that is physically and/or logically coupled, or may directly and/or indirectly connect two or more devices that are physically and/or logically separated. Physically (for example, by wire and/or wirelessly), and may be realized by a plurality of these devices.

For example, the S-GW1 or the like may function as a computer that performs the paging process of the present invention. FIG. 4 is a diagram illustrating an example of the hardware configuration of the S-GW 1. The S-GW1 described above may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In the following description, the word "device" can be read as a circuit, a device, a unit, or the like. The hardware configuration of the S-GW 1 may be configured to include one or a plurality of each device illustrated in the figure, or may be configured not to include some devices.

Each function in the S-GW 1 causes a predetermined software (program) to be loaded on hardware such as the processor 1001 and the memory 1002, so that the processor 1001 performs an arithmetic operation, communication by the communication device 1004, and the memory 1002 and the storage 1003. It is realized by controlling the reading and/or writing of data in.

The processor 1001 operates an operating system to control the entire computer, for example. The processor 1001 may be configured by a central processing unit (CPU) including an interface with peripheral devices, a control device, a calculation device, a register, and the like. For example, the fault monitoring unit 10, the downlink communication receiving unit 12, the fault determining unit 13, the paging transmitting unit 14, and the like described above may be implemented by the processor 1001.

Further, the processor 1001 reads a program (program code), a software module, and data from the storage 1003 and/or the communication device 1004 into the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least part of the operations described in the present embodiment is used. For example, the fault monitoring unit 10, the downlink communication receiving unit 12, the fault determining unit 13, the paging transmitting unit 14, and the like of the S-GW 1 may be realized by a control program stored in the memory 1002 and operating by the processor 1001. The functional block of may be similarly realized. Although it has been described that the various processes described above are executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may be transmitted from the network via an electric communication line.

The memory 1002 is a computer-readable recording medium, and is configured by, for example, at least one of ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), and the like. May be done. The memory 1002 may be called a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store programs (program codes) that can be executed to implement the paging method according to the present embodiment, software modules, and the like.

The storage 1003 is a computer-readable recording medium, for example, an optical disc such as a CD-ROM (Compact Disc ROM), a hard disc drive, a flexible disc, a magneto-optical disc (for example, a compact disc, a digital versatile disc, a Blu-ray disc). (Registered trademark) disk), a smart card, a flash memory (for example, a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, or the like. The storage 1003 may be called an auxiliary storage device. The storage medium described above may be, for example, a database including the memory 1002 and/or the storage 1003, a server, or another appropriate medium. For example, the failure information storage unit 11 and the like described above may be realized by the storage 1003.

The communication device 1004 is hardware (transmission/reception device) for performing communication between computers via a wired and/or wireless network, and is also called, for example, a network device, a network controller, a network card, a communication module, or the like. For example, the downlink communication receiving unit 12 and the paging transmitting unit 14 described above may be realized by the communication device 1004.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated (for example, a touch panel).

Further, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured with a single bus or different buses among devices.

The S-GW1 includes hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). It may be configured, and a part or all of each functional block may be realized by the hardware. For example, processor 1001 may be implemented with at least one of these hardware.

Hereinafter, each functional block of the S-GW 1 shown in FIG. 3 will be described. As a premise, it is assumed that the S-GW1 is the S-GW1 included in the mobile communication system 7 (the UE5 is currently accommodated in the Decoror 2-2, etc.) shown in FIG.

The failure monitoring unit 10 monitors a failure of the MME 2 managed by the S-GW 1 and a failure of the core network formed by the MME 2. Specific examples of the failure include life and death of the device, device failure, and network congestion. For example, the fault monitoring unit 10 monitors a fault by periodically polling each MME 2, and when a fault is detected, generates fault information related to the fault and stores it in the fault information storage unit 11. The failure information includes the identification information of the failed device, the identification information of the failed network, and the information indicating the details of the failure.

The failure information storage unit 11 stores failure information of the MME 2 managed by the S-GW 1 and failure information of the core network formed by the MME 2. For example, the failure information storage unit 11 stores failure information of the MME2 of the default CN2-1, failure information of the default CN2-1, failure information of the MME2 of Decor2-2, failure information of the Decor2-2, and the like. The fault information storage unit 11 does not store the fault information of the MME2 of the default CN2-1 and the fault information of the default CN2-1, but stores the fault information of the MME2 of the Decor2-2 and the fault information of the Decor2-2. May be. The failure information storage unit 11 may store other information regarding the MME 2 managed by the S-GW 1 and the core network formed by the MME 2.

The downlink communication receiving unit 12 receives downlink communication (information in the downlink direction toward the UE 5) from the P-GW 3. As a specific example of the downlink communication, communication (information) from an opposite device which is a communication partner of the UE 5 can be cited. The downlink communication receiving unit 12 may receive downlink communication from another device. The downlink communication receiving unit 12 outputs the received downlink communication to the failure determining unit 13.

When the failure determination unit 13 receives the downlink communication to the UE 5, the failure determination unit 13 determines whether the failure information stored in the failure information storage unit 11 indicates whether or not a failure has occurred in the MME 2 of the Decor 2-2 that performs the call processing of the downlink communication. Judgment based on Specifically, when the downlink communication is input from the downlink communication receiving unit 12, the failure determination unit 13 acquires the identification information of the MME 2 to be the target of the downlink communication by the conventional technique. For example, the failure determination unit 13 acquires the identification information of the MME 2 based on the identification information included in the downlink communication and the information stored in advance in the S-GW 1. Next, the failure determination unit 13 acquires the identification information of the core network formed by the MME 2 that is the target of the downlink communication by the conventional technique. For example, the failure determination unit 13 acquires the identification information of the core network based on the identification information included in the downlink communication, the acquired identification information of the MME 2, the information stored in advance in the S-GW 1, and the like.

Next, the failure determination unit 13 determines, based on the acquired identification information of the core network, whether or not the downlink communication is for a predetermined core network, here, the communication for the Decor 2-2. When the failure determination unit 13 determines that the communication is for the Decor 2-2, the failure determination unit 13 next compares the acquired identification information of the MME 2 with the identification information of the MME 2 included in the failure information stored by the failure information storage unit 11. By doing so, it is determined whether or not a failure has occurred in the MME 2 of the Decor 2-2 that is the target of downlink communication. It should be noted that the failure determination unit 13 omits the determination as to whether or not the downlink communication is communication for a predetermined core network, and directly determines whether or not a failure has occurred in the MME 2 that is the target of the downlink communication. May be. Next, the failure determination unit 13 outputs the determination result to the paging transmission unit 14. The determination result is a flag value indicating whether or not a failure has occurred, and, if a failure has occurred, identification information of the MME2 in which the failure has occurred (or group identification information of the MME group to which the MME2 belongs). “MMEGI” (MME Group ID), identification information of the Decor 2-2 to which the MME 2 belongs, and the like.

When the downlink communication is received, the failure determination unit 13 further determines whether or not a failure has occurred in the default CN 2-1 based on the failure information stored in the failure information storage unit 11, in addition to the above determination. You may. Since the determination method is the same as that described above, description thereof will be omitted.

When the failure determination unit 13 determines that the MME 2 has a failure, the paging transmission unit 14 includes the MME 2 of the default CN 2-1 as an MME 2 candidate (call processing node candidate) for transmitting paging. , MME2 is selected from the MME2 candidates, and paging is transmitted to the selected MME2. Specifically, when the determination result input from the failure determination unit 13 is information indicating that a failure has occurred in the MME 2, the paging transmission unit 14 determines that a failure has occurred as a MME2 candidate for transmitting paging. The MME2 of the default CN2-1 that is the default core network is included in addition to the MME2 of the Decor2-2 (other than the MME2 in which the failure has occurred) that is the core network that is operating. It should be noted that the paging transmission unit 14 does not include the MME2 of the decorating core network Decor2-2 as an MME2 candidate for transmitting the paging, but includes only the MME2 of the default CN2-1 that is the default core network. May be. Next, the paging transmission unit 14 selects the MME2 from the MME2 candidates by a predetermined method. For example, the paging transmission unit 14 may randomly select the MME2 from the MME2 candidates, or may sequentially select the MME2 by round robin. Next, the paging transmission unit 14 transmits paging to the selected MME2.

In addition, when the failure determination unit 13 determines that the MME 2 has a failure and the default CN 2-1 does not have a failure (the limitation), the paging transmission unit 14 determines the MME 2 candidate. Alternatively, the MME2 of the default CN2-1 may be included, the MME2 is selected from the MME2 candidates, and paging may be transmitted to the selected MME2. The determination that no fault has occurred in the default CN 2-1 is performed based on the determination result input from the fault determination unit 13 as in the above.

When transmitting the paging to the selected MME 2, the paging transmission unit 14 includes the fault node information regarding the MME 2 of the Decor 2-2, which is determined to have a fault by the fault determination unit 13, in the paging and transmits the paging. Good. As a specific example of the faulty node information, it is the identification information of the MME2 in which the fault has occurred, the identification information of the Decor 2-2 to which the MME2 belongs, and the destination of the downlink communication, which are included in the determination result input from the fault determination unit 13. Examples include “UE Usage Type”, which is terminal usage type identification information indicating the characteristics of the usage of the UE 5, and “MMEGI” which is identification information of the MME 2 in which a failure has occurred. In the sequence diagrams of FIGS. 7 and 8 described later, paging includes “UE Usage Type” and “MMEGI” as faulty node information. Note that “UE Usage Type” and “MMEGI” are specified in 3GPP.

FIG. 5 is a functional block diagram of the MME 2. As shown in FIG. 5, the MME 2 includes a paging reception unit 20, a faulty node information storage unit 21, an attach reception unit 22, an attachment target determination unit 23, and an attachment processing unit 24.

The functional block diagram shown in FIG. 5 shows functional blocks. These functional blocks (components) are realized by an arbitrary combination of hardware and/or software. Further, the means for realizing each functional block is not particularly limited. That is, each functional block may be implemented by one device that is physically and/or logically coupled, or may directly and/or indirectly connect two or more devices that are physically and/or logically separated. Physically (for example, by wire and/or wirelessly), and may be realized by a plurality of these devices.

For example, the MME 2 or the like may function as a computer that performs the paging process of the present invention. FIG. 6 is a diagram illustrating an example of the hardware configuration of the MME 2. The MME 2 described above may be physically configured as a computer device including a processor 2001, a memory 2002, a storage 2003, a communication device 2004, an input device 2005, an output device 2006, a bus 2007, and the like.

The hardware configuration of the MME 2 may be configured to include one or a plurality of each device illustrated in the figure, or may be configured not to include some devices.

Each function in the MME 2 causes a predetermined software (program) to be loaded on hardware such as the processor 2001 and the memory 2002, so that the processor 2001 performs calculation, communication by the communication device 2004, and data in the memory 2002 and the storage 2003. It is realized by controlling reading and/or writing of the.

The processor 2001 operates an operating system to control the entire computer, for example. The processor 2001 may be configured by a central processing unit including an interface with peripheral devices, a control device, an arithmetic unit, a register, and the like. For example, the paging receiving unit 20, the attach receiving unit 22, the attach target determining unit 23, the attach processing unit 24, and the like described above may be realized by the processor 2001.

Further, the processor 2001 reads programs, software modules, and data from the storage 2003 and/or the communication device 2004 into the memory 2002, and executes various processes according to these. As the program, a program that causes a computer to execute at least part of the operations described in the present embodiment is used. For example, the paging receiving unit 20, the attach receiving unit 22, the attach target determining unit 23, the attach processing unit 24, and the like of the MME 2 may be realized by a control program stored in the memory 2002 and operating by the processor 2001, and other functions. The blocks may be similarly realized. Although it has been described that the various processes described above are executed by one processor 2001, they may be executed simultaneously or sequentially by two or more processors 2001. The processor 2001 may be implemented by one or more chips. The program may be transmitted from the network via an electric communication line.

The memory 2002 is a computer-readable recording medium, and may be composed of at least one of ROM, EPROM, EEPROM, RAM, and the like. The memory 2002 may be called a register, a cache, a main memory (main storage device), or the like. The memory 2002 can store a program (program code) that can be executed to implement the paging method according to the present embodiment, a software module, and the like.

The storage 2003 is a computer-readable recording medium, and is composed of, for example, at least one of an optical disk such as a CD-ROM, a hard disk drive, a flexible disk, a magneto-optical disk, a smart card, a flash memory, a floppy disk, and a magnetic strip. May be done. The storage 2003 may be called an auxiliary storage device. The storage medium described above may be, for example, a database including the memory 2002 and/or the storage 2003, a server, or other appropriate medium. For example, the failed node information storage unit 21 and the like described above may be realized by the storage 2003.

The communication device 2004 is hardware for performing communication between computers via a wired and/or wireless network, and is also called, for example, a network device, a network controller, a network card, a communication module, or the like. For example, the paging reception unit 20 and the attachment processing unit 24 described above may be realized by the communication device 2004.

The input device 2005 is an input device that receives an input from the outside. The output device 2006 is an output device that implements output to the outside. The input device 2005 and the output device 2006 may be integrated.

Further, each device such as the processor 2001 and the memory 2002 is connected by a bus 2007 for communicating information. The bus 2007 may be configured with a single bus or different buses between devices.

The S-GW1 may be configured to include hardware such as a microprocessor, a digital signal processor, an ASIC, a PLD, and an FPGA, and even if a part or all of each functional block is realized by the hardware. Good. For example, processor 2001 may be implemented with at least one of these hardware.

Hereinafter, each functional block of the MME 2 shown in FIG. 5 will be described. In addition, as a premise, the MME2 is the MME2 included in the mobile communication system 7 illustrated in FIG. 2, and is the MME2-1-1 of the default CN2-1 that receives the paging transmitted from the S-GW1. Suppose.

The paging receiving unit 20 receives the paging transmitted from the S-GW 1, and includes the failure node information regarding the MME 2 of the Decor 2-2, which is included in the received paging and which is determined by the failure determination unit 13 that a failure has occurred. The faulty node information acquired is stored in the faulty node information storage unit 21.

The faulty node information storage unit 21 stores faulty node information. The faulty node information storage unit 21 may store (hold) the faulty node information for a certain period of time and discard the faulty node information after a certain period of time.

The attach reception unit 22 receives the attach transmitted from the UE 5 via the eNB 4 or the like. The attach includes various information included in the related art. The attach receiving unit 22 outputs the received attach to the attach target determining unit 23.

When the attach target determination unit 23 receives the attach from the UE 5, the attach target determination unit 23 determines whether or not the attach target matches the target indicated by the faulty node information stored by the faulty node information storage unit 21. Specifically, when the attach is input from the attach receiving unit 22, the fault node information storage unit 21 stores various information included in the attach, the fault node information stored by the fault node information storage unit 21, and the MME 2 in advance. It is determined whether the target of attachment matches the target indicated by the faulty node information, based on the acquired information and the information obtained as a result of inquiring the external device such as the HSS6. For example, the attachment target determination unit 23 identifies the MME 2 in which a failure has occurred, which is included in the identification information of the MME 2 that is the attachment target included in the attachment and the failure node information stored by the failure node information storage unit 21. It is determined whether or not the information matches. In addition, for example, the attach target determination unit 23, the attach target determination unit 23, as a result of inquiring the HSS 6 with the identification information (IMSI or the like) of the UE 5 included in the attach as a key, the acquired “UE Usage Type” and the acquired “ It is determined whether or not “MMEGI” stored in the MME 2 in association with “UE Usage Type” matches the “UE Usage Type” and “MMEGI” included in the faulty node information. The attachment determination unit 23 outputs the determination result to the attachment processing unit 24. The determination result includes a flag value indicating whether or not the target of attachment matches the target indicated by the faulty node information.

When the attachment processing determination unit 23 determines that the attachment target determination unit 23 matches the target indicated by the faulty node information, the attachment processing unit 24 performs processing with the MME 2 other than the target as the attachment target. Specifically, if the determination result input from the attachment target determination unit 23 is information indicating that the target of attachment matches the target indicated by the faulty node information, the attach processing unit 24 determines that the target other than the target is not attached. The process for attaching the MME 2 is performed. In addition, when the attach target determination unit 23 determines that the attached target determination unit 23 matches the target indicated by the faulty node information, the attach processing unit 24 performs a process in which the MME 2 of the core network other than the core network formed by the target is set as the attach target. The process may be performed, the MME2 of the default core network may be subjected to the process of attaching, or the other predetermined MME2 may be performed of the process of attaching.

Subsequently, the paging processing in the S-GW 1 and MME 2 according to the present embodiment will be described using the sequence diagrams shown in FIGS. 7 and 8. Note that the processing of FIGS. 7 and 8 continues, and when the processing advances to A of FIG. 7, the processing continues from A of FIG. Further, as a premise, it is assumed that the S-GW1 and the MME2 are the S-GW1 and the MME2 included in the mobile communication system 7 (the UE 5 is currently accommodated in the Decoror 2-2, for example) shown in FIG.

In FIG. 7, the failure information storage unit 11 of the S-GW 1 manages the core network (default CN 2-1 or Decor 2-2) to which each MME 2 (included in the mobile communication system 7) managed by the S-GW 1 belongs. The information of) is stored (held) (S20). Next, the failure monitor 10 of the S-GW 1 (periodically) monitors the life and death of the Decoror 2-2 (S21). Next, the failure monitoring unit 10 of the S-GW 1 (periodically) monitors the congestion of the default CN 2-1 (S22). Note that S21 and S22 may be performed at any timing. After S22, the failure information storage unit 11 of the S-GW 1 stores information regarding the congestion state of the default CN 2-1 (S23). Next, when a failure occurs in the Decoror 2-2 (S24), the failure monitoring unit 10 of the S-GW1 detects the failure (failure of S24) (S25), and failure information regarding the detected failure is stored in the S-GW1. It is stored by the failure information storage unit 11 (S26).

Next, the downlink communication receiving unit 12 of the S-GW 1 receives the downlink communication from the P-GW 3 (S27). Next, the failure determination unit 13 of the S-GW 1 determines by the failure information storage unit 11 whether or not the downlink communication received in S27 is directed to the MME2 (MME2-2-1) of the Decor 2-2 in failure. A determination is made based on the stored failure information (S28, failure determination step). If it is determined in S28 that the failure is not for the MME2 of the Decor 2-2 (S28: NO), normal call processing is continued in the S-GW1 and the entire mobile communication system 7 (S29). On the other hand, if it is determined in S28 that it is for the MME2 of the Decor2-2 in failure (S28: YES), then the S-GW1 determines whether or not the default CN2-1 is congested. A determination is made based on the failure information stored in the storage unit 11 (S30, failure determination step). When it is determined in S30 that the default CN 2-1 is congested (S30: YES), the paging transmission unit 14 of the S-GW 1 determines that the paging destination is from the MME 2 (other than the faulty MME 2) of the Decor 2-2. Selected and paging is transmitted (S31). On the other hand, when it is determined in S30 that the default CN 2-1 is determined not to be congested (S30: YES), the paging transmission unit 14 of the S-GW1 includes “UE Usage Type” and “MMEGI”. The paging request is transmitted to (the MME2 (MME2-1-1) of the default CN 2-1) (S32, paging transmission step). Next, the paging reception unit 20 of the default CN 2-1 receives the paging transmitted in S32, and the faulty node information storage unit 21 of the default CN 2-1 indicates “UE Usage Type” and “MMEGI” included in the paging. It is stored for a fixed time (S33). Next, paging (IMSI Paging) is transmitted to the UE 5 by the default CN 2-1 (S34).

Moving to FIG. 8, after S34, the UE 5 transmits the attach to (the MME 2 of) the default CN 2-1 (S35). Next, the attach reception unit 22 of the default CN 2-1 receives the attach transmitted in S35, and the attach target determination unit 23 of the default CN 2-1 inquires of the HSS 6 about “UE Usage Type” (Dia_ULR( (Update Location Request) is transmitted) (S36). Next, the HSS 6 returns "UE Usage Type" as a response in S36 (transmission of Dia_ULA (Update Location Answer)) (S37). Next, the attach target determination unit 23 of the default CN 2-1 determines whether or not the attach target is the Decor 2-2 to which the failed MME 2 belongs (S38). When it is determined in S38 that the target of attachment is not the Decor2-2 to which the failed MME2 belongs (S38: NO), the attach processing unit 24 of the default CN 2-1 redirects the attach to the Decor2-2. (S39). On the other hand, if it is determined in S38 that the target of the attach is the Decor2-2 to which the failed MME2 belongs (S38: YES), the attach processing unit 24 of the default CN 2-1 redirects the attach to the Decor2-2. Instead, it is processed as an attachment to the default CN 2-1 (S40).

Next, the function and effect of the S-GW1 and MME2 configured as in this embodiment will be described.

According to the S-GW1 of the present embodiment, paging is performed when it is determined that the downlink communication for the UE5 is received and the MME2 of the Decor2-2 that performs the call processing of the downlink communication has a failure (such as a failure). The MME2 of the default CN 2-1 is included as the MME2 candidate for transmitting the MME2, the MME2 is selected from the MME2 candidates, and the paging is transmitted to the selected MME2. If such a configuration is adopted, since the MME 2 of the default CN 2-1 is also targeted as the destination of paging, the processing load of paging is distributed to the default CN 2-1 and the processing load of the failed Decor 2-2 is reduced. You can

Further, when it is determined that the MME2 of the Decor 2-2 that performs the downlink communication call processing has a failure, it is further determined that the default CN 2-1 has no failure (such as congestion). By adding the condition "when the paging is performed", paging can be realized in consideration of the processing load of the default CN 2-1.

Moreover, the paging transmission unit 14 of the S-GW 1 sequentially selects the MME 2 from the MME 2 candidates by round robin, and thus transmits the failure node information to different MME 2 in order every time the S-GW 1 receives the downlink communication. , The MME 2 can store the faulty node information. That is, even if the faulty node information is not transmitted to all MMEs 2 at once, the load on the entire network is suppressed by transmitting faulty node information to one MME 2 in order every time the S-GW 1 receives downlink communication. At the same time, the faulty node information can be spread to all MMEs 2.

Further, by adopting “MMEGI” as the failure node information, it is possible to perform not only the single MME2 that has failed, but also the MME2 group that belongs to the same core network or pool as the failed MME2, for example. Further, by further adopting the “UE Usage Type” as the faulty node information, the UE 5 groups having the same “UE Usage Type” (that is, having the same usage type) are not uniformly applied to the single UE 5. The core network can be distributed to each other. Further, “MMEGI” and “UE Usage Type” are information defined by 3GPP, and the invention according to the present embodiment can be applied without changing the existing standard.

Further, according to the MME 2 of the present embodiment, when the attach target is determined to match the target indicated by the faulty node information when the attach is received from the UE 5, the MME 2 other than the target is set as the attach target. The processing is performed. With such a configuration, since the attach is not redirected to the MME2 of the Decoror 2-2, it is possible to reduce the processing load of the return attach in the MME 2 of the Decoror 2-2.

Further, the faulty node information storage unit 21 of the MME 2 stores the faulty node information for a certain period of time, so that, for example, when the fault of the faulty MME 2 is recovered after a while, the normal distribution process is performed. Since the process returns, the distribution process can be continued as usual even after recovery from the failure without providing a special function.

As described above, in the mobile communication system 7 including the S-GW 1 and the MME 2 of the present embodiment, if downlink communication occurs and the target MME 2 is out of order and call processing cannot be continued, S- Added a process to determine that the target MME2 is the MME2 of Decor2-2 and that the default CN2-1 is not congested in GW1, and select the MME2 subject to paging (IMSI Paging) from the default CN2-1 as well. To do. Further, after that, the attach process executed by the UE 5 by returning is also prevented from returning the Decor 2-2 to the MME 2, so that the load-balanced MME 2 increases and congestion of the entire network can be prevented without additional equipment. .. Further, even if the MME 2 of the Decoror 2-2 is completely disconnected by this function, the subscriber's communication can be continued using the MME 2 of the default CN 2-1.

Each aspect/embodiment described in this specification is LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA. (Registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-WideBand), It may be applied to a system using Bluetooth (registered trademark), another suitable system, and/or a next-generation system extended based on these.

As long as there is no contradiction, the order of the processing procedure, sequence, flowchart, etc. of each aspect/embodiment described in this specification may be changed. For example, the methods described herein present elements of the various steps in a sample order, and are not limited to the specific order presented.

In the present specification, a particular operation performed by a particular device may be performed by its upper node in some cases. For example, when the specific device is a base station, various operations performed for communication with a terminal in a network including one or a plurality of network nodes having the base station include: Obviously, it may be performed by the base station and/or other network nodes other than the base station, such as, but not limited to, MME or S-GW. Although the case where there is one network node other than the base station has been illustrated above, a combination of a plurality of other network nodes (for example, MME and S-GW) may be used.

Information or the like may be output from the upper layer (or lower layer) to the lower layer (or upper layer). Input/output may be performed via a plurality of network nodes.

The input/output information and the like may be stored in a specific place (for example, a memory) or may be managed by a management table. Information that is input/output may be overwritten, updated, or added. The output information and the like may be deleted. The input information and the like may be transmitted to another device.

The determination may be performed by a value represented by 1 bit (whether 0 or 1), may be performed by a Boolean value (Boolean: true or false), and may be performed by comparing numerical values (for example, a predetermined value). (Comparison with the value).

The aspects/embodiments described in the present specification may be used alone, in combination, or may be switched according to execution. Further, the notification of the predetermined information (for example, the notification of “being X”) is not limited to the explicit notification, and is performed implicitly (for example, the notification of the predetermined information is not performed). Good.

Although the present invention has been described in detail above, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments described herein. The present invention can be implemented as modified and changed modes without departing from the spirit and scope of the present invention defined by the description of the claims. Therefore, the description of the present specification is for the purpose of exemplifying explanation, and does not have any restrictive meaning to the present invention.

Software, whether called software, firmware, middleware, microcode, hardware description language, or any other name, instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules , Application, software application, software package, routine, subroutine, object, executable, thread of execution, procedure, function, etc. should be construed broadly.

Moreover, software, instructions, etc. may be transmitted and received via a transmission medium. For example, the software may use a wired technology such as coaxial cable, fiber optic cable, twisted pair and digital subscriber line (DSL) and/or wireless technology such as infrared, wireless and microwave to websites, servers, or other When transmitted from a remote source, these wireline and/or wireless technologies are included within the definition of transmission medium.

The information, signals, etc. described herein may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description include voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any of these. May be represented by a combination of

Note that the terms described in the present specification and/or terms necessary for understanding the present specification may be replaced with terms having the same or similar meanings. For example, channels and/or symbols may be signals. The signal may also be a message. Further, the component carrier (CC) may be called a carrier frequency, a cell, or the like.

As used herein, the terms “system” and “network” are used interchangeably.

In addition, the information, parameters, and the like described in this specification may be represented by absolute values, relative values from predetermined values, or may be represented by other corresponding information. .. For example, the radio resources may be those designated by the index.

The names used for the above parameters are not limiting in any way. Further, the mathematical formulas and the like that use these parameters may differ from those explicitly disclosed herein. Since different channels (eg PUCCH, PDCCH, etc.) and information elements (eg TPC, etc.) can be identified by any suitable name, the different names assigned to these different channels and information elements are However, it is not limited.

A base station can accommodate one or more (eg, three) cells (also called sectors). When a base station accommodates a plurality of cells, the entire coverage area of the base station can be divided into a plurality of smaller areas, each smaller area being defined by a base station subsystem (eg, small indoor base station RRH:Remote). The communication service can also be provided by the Radio Head. The term "cell" or "sector" refers to part or all of the coverage area of a base station and/or base station subsystem that provides communication services in this coverage. Further, the terms "base station", "eNB", "cell", and "sector" may be used interchangeably herein. A base station may be referred to as a fixed station, a NodeB, an eNodeB (eNB), an access point, a femtocell, a small cell, or the like.

Mobile communication terminals are defined by those skilled in the art as subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, It may also be referred to as a wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

As used herein, the phrase "based on" does not mean "based only on," unless expressly specified otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

When the designations "first," "second," etc. are used herein, any reference to that element does not generally limit the amount or order of those elements. These designations may be used herein as a convenient way to distinguish between two or more elements. Thus, references to the first and second elements do not imply that only two elements may be employed therein, or that the first element must precede the second element in any way.

As long as the terms "including", "comprising", and variations thereof are used herein or in the claims, these terms are inclusive, as well as the term "comprising." Intended to be objective. Furthermore, the term "or" as used in the specification or claims is not intended to be an exclusive OR. In this specification, a plurality of devices are also included unless the context or technology clearly indicates that only one device exists.

Throughout this disclosure, where articles are added by translation, for example “a”, “an” and “the” in English, it is clear from context that these articles are not. If not, multiple items are included.

1... S-GW, 2... MME, 2-1... Default CN, 2-2... Decor, 3... P-GW, 4... eNB, 5... UE, 6... HSS, 7... Mobile communication system, 10... Fault monitoring unit, 11... Fault information storage unit, 12... Downlink communication reception unit, 13... Fault determination unit, 14... Paging transmission unit, 20... Paging reception unit, 21... Fault node information storage unit, 22... Attach reception unit, 23... Attach target determination unit, 24... Attach processing unit.

Claims (2)

A gateway device,
And fault information of the first core network, and a different fault information storage unit in which one of the mobile communication terminal stores the failure information of the second core network that are currently accommodated from the first core network,
When receiving downlink communication to the mobile communication terminal,
Determining whether or not a failure has occurred in the call processing node of the second core network that performs the call processing of the downlink communication, based on the failure information stored by the failure information storage unit ,
Determined based on the first failure information stored whether the core network problem by the failure information storage unit,
A failure determination unit,
By the fault determining unit, when a failure in the call processing node is determined to have occurred, and failure in the first core network is determined not to have occurred, as the call processing node candidates of transmitting the paging A paging transmitter that includes a call processing node of the first core network, selects a call processing node from the call processing node candidates, and transmits the paging to the selected call processing node;
A gateway device including
A paging reception call processing node that is a call processing node of the first core network that has received the paging transmitted from the gateway device,
A failure node information storage unit that stores failure node information included in the paging by the paging transmission unit and related to a call processing node of the second core network that is determined to have a failure by the failure determination unit;
When receiving an attach from the mobile communication terminal, an attach target determination unit that determines whether or not the target of the attach matches the target indicated by the fault node information stored by the fault node information storage unit,
When it is determined by the attach target determination unit that the target indicated by the faulty node information matches, an attach processing unit that performs a process in which a call processing node other than the target is the target of the attach,
A paging received call processing node comprising:
A communication system including . And fault information of the first core network, the first differs from the first core network gateway device having a failure information storage unit in which one of the mobile communication terminal stores the failure information of the second core network that are currently accommodated , When receiving downlink communication to the mobile communication terminal,
Determining whether or not a failure has occurred in the call processing node of the second core network that performs the call processing of the downlink communication, based on the failure information stored by the failure information storage unit ,
Determined based on the first failure information stored whether the core network problem by the failure information storage unit,
Failure determination step,
The gateway device transmits paging when it is determined in the failure determination step that the call processing node has a failure and that the first core network has not failed. A paging transmitting step of including a call processing node of the first core network as a call processing node candidate, selecting a call processing node from the call processing node candidates, and transmitting the paging to the selected call processing node;
A paging reception call processing node that is a call processing node of the first core network that has received the paging transmitted from the gateway device, and has a failure in the failure determination step included in the paging in the paging transmission step. When a paging reception call processing node including a failure node information storage unit that stores failure node information related to the call processing node of the second core network determined to have received an attach from the mobile communication terminal In, the attachment target determination step of determining whether the target of attachment matches the target indicated by the faulty node information stored by the faulty node information storage unit,
If the paging reception call processing node is determined to match the target indicated by the faulty node information in the attach target determination step, an attach processing step that performs a process in which a call processing node other than the target is the target of the attach When,
Paging method including.

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