JP6783262B2 - Node device and its control method, and program - Google Patents

Description

The present invention relates to a node device for edge computing in a mobile network, a control method thereof, and a program.

The ETSI (European Telecommunications Standards Institute) is promoting the standardization of multi-access edge computing (MEC). When applying MEC to a mobile network, a node device (for example, between a base station and a core network) that provides IT services to a user device (UE: User Equipment) in a base station cell near the edge of the network. MEC node) is provided. The MEC node identifies packets transmitted between the base station and a core network node such as a gateway device inline using, for example, DPI (Deep Packet Inspection) technology, analyzes the contents, and analyzes the contents, if necessary. Performs processing by the application running on the MEC node.

Further, in the mobile network as described above, when the communication with the UE is started from the network side, a movement management device such as an MME (Mobility Management Entity) performs a UE call (paging) process. The MME performs paging of the UE via one or more base stations based on the service area information held according to the location registration from the UE. The paging range (paging area) corresponding to the geographical area where the UE is paging is determined according to a predetermined policy (paging policy).

For example, Patent Document 1 discloses a mechanism for allocating an optimum paging area size based on a movement frequency and a communication frequency for each wireless terminal (UE). Patent Document 2 discloses a mechanism for optimizing the paging area in consideration of radio access network (RAN) and UE-specific information. Patent Document 3 discloses a mechanism for determining a paging area using a list of base stations in which a mobile station is likely to be located, which is created based on a prediction result of a mobile station's mobile state.

Japanese Unexamined Patent Publication No. 2008-193592 Special Table 2016-514935 International Publication No. 2014/049911

The paging policy for the paging process is determined from the viewpoint of balancing the transaction load of the MME associated with the paging process and the paging delay until the paging is successful. It is desirable that this paging policy be appropriately determined for each UE, as in the prior art described above. However, the MME usually accommodates a significant number of UEs present in cells formed by a large number of base stations housed in the MME. Therefore, the MME centrally manages history information such as movement history for each UE, and sets a different paging policy for each UE and performs paging processing based on the history information as in the above-mentioned prior art. Is actually difficult.

Therefore, by using the MEC node arranged between the MME and the plurality of base stations, it may be possible to control the paging process on a UE-by-UE basis. In that case, the MEC node acquires the encryption information (encryption key) for each UE for the analysis of the encrypted signaling information contained in the packet transmitted between the MME and each base station. There is a need to. This encrypted information can be obtained, for example, from signaling information exchanged between the UE and the MME. However, unless the UE performs a handover accompanied by movement between MMEs or an attach involving terminal authentication (IMSI attach, etc.), signaling information including encrypted information is not exchanged between the UE and MME, and the MEC node encrypts. It may not be possible to obtain the encryption information.

The present invention has been made in view of the above-mentioned problems. An object of the present invention is to provide a technique for acquiring encrypted information necessary for analysis of encrypted signaling information in a MEC node that controls paging processing for each UE, which is arranged in a mobile network. It is said.

The node device according to one aspect of the present invention is a node device for edge computing arranged between a plurality of base stations and a movement management device in a core network, and each of the plurality of base stations. By analyzing the signaling information contained in the packet transmitted between the mobile terminal and the mobile management device, information for adjusting the paging range in the paging of the wireless terminals existing in the cells of the plurality of base stations is collected. When the node device does not hold the analysis means to be used and the encrypted information that can be used to decrypt the encrypted signaling information about the wireless terminal in the analysis by the analysis means, the wireless terminal is authenticated. A control means for transmitting a control signal for causing the wireless terminal to reattach to the core network, and the wireless terminal and the movement management device in the connection process for the reattachment. It is characterized by including an acquisition means for acquiring the encrypted information from the transmitted signaling information.

According to the present invention, it is possible to acquire the encrypted information necessary for analyzing the encrypted signaling information in the MEC node that controls the paging process for each UE, which is arranged in the mobile network. As a result, the MEC node analyzes the signaling information transmitted between the UE or base station and the MME using the acquired encrypted information, and controls the paging process on a UE-by-UE basis based on the collected information. Becomes possible.

The figure which shows the example of the network configuration including the MEC node Block diagram showing a hardware configuration example of a MEC node Block diagram showing a functional configuration example of a MEC node Diagram showing an example of information managed by the MEC node (information management department) Flowchart showing the procedure of processing executed by the MEC node A flowchart showing the procedure of the terminal registration process (S6) A flowchart showing the procedure of the information update process (S8) Flow chart showing the procedure of paging control (S12) The figure which shows the example of the paging control by a MEC node. Flowchart showing the procedure of reconnection control by MEC node Diagram showing the communication sequence related to the acquisition of encrypted information by reconnection control The figure which shows the example of the paging process by MME

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In each of the following figures, components not necessary for the description of the embodiment will be omitted from the drawings.

In the embodiments described below, an LTE / LTE-Advanced network is assumed as an example of a mobile network to which the present invention is applied. The present invention may be applied to mobile networks other than LTE networks. For example, the present invention may be applied to a fifth generation (5G) mobile network that is being standardized in a third generation partnership project (3GPP).

<Network configuration>
The LTE network assumed in the present embodiment is composed of an E-UTRAN (Evolved Universal Terrestrial Radio Network) which is a radio access network and an EPC (Evolved Packet Core) which is a core network. E-UTRAN is composed of a large number of base stations (base station devices). In LTE, a base station is referred to as an eNodeB (hereinafter referred to as "eNB"). The eNBs are connected to each other via the X2 interface. Further, each eNB is directly connected to the EPC via the S1 interface. Both the X2 interface and the S1 interface are logical interfaces. The S1 interface is composed of an S1-U interface for transmitting a user plane (U-Plane) signal (user data) and an S1-MME interface for transmitting a control signal. The S1-U interface connects each eNB with an S-GW (Serving Gateway) which is a gateway device. The S1-MME interface connects each eNB and an MME (movement management device).

FIG. 1 is a diagram showing an example of a network configuration including a MEC node 10 which is a node device according to an embodiment of the present invention. The MEC node 10 is a node device for edge computing (MEC in this embodiment). FIG. 1 shows MME11 and S-GW12 of EPC as an example of a movement management device and a gateway device in a core network, respectively. In the 5G mobile network, which is being standardized, the mobility management device is called an AMF (Access and Mobility Management Function), and the gateway device is called an UPF (User Plane Function).

In the present embodiment, as shown in FIG. 1, the MEC node 10 is arranged (on the control channel between the eNB and the MME 11) between the plurality of eNBs housed in the MME 11 and the EPC including the MME 11. .. As a result, at least a part of the large number of eNBs housed in the MME 11 is housed in the MEC node 10, and the MEC node 10 is housed in the MME 11. The MEC node 10 has a function (DPI function) of analyzing (decoding) the contents of a packet transmitted between the eNB and the EPC via the S1 interface (S1-U interface or S1-MME interface). It is composed of.

The MEC node 10 can accommodate an arbitrary number of eNBs, not limited to the five eNBs as in the example of FIG. Further, one MME 11 may accommodate a plurality of MEC nodes 10 accommodating different eNB groups. Note that the network configuration example of FIG. 1 shows a functional configuration and does not necessarily show a physical configuration. For example, the MEC node 10 may be physically mounted in the same housing as the gateway device (S-GW or P-GW (Packet Data Network Gateway)).

<Paging process>
Here, with reference to FIG. 12, the outline of the paging process in the LTE network, which is the premise of the present embodiment, will be described.

The MME manages a plurality of TAs (tracking areas) in order to manage the position of the wireless terminal (UE). Each TA is a cell unit indicating the position of the UE, which is composed of one or more eNBs (one or more cells). The MME lists one or more TAs for each UE, generates a TAI list (TAI-List) which is a list of the identifiers (TAIs) of the one or more TAs, and assigns the TAs to the UEs. The TAI list usually includes the TAI of the TA to which the UE was most recently located. In the example of FIG. 12, the MME manages three TAs (TA # 1, TA # 2, TA # 3) and assigns a TAI list consisting of TA # 1 and TA # 2 TAIs to the UE. ..

The TAI list corresponds to an area (TA group) in which it is not necessary to make a location registration request to the MME as long as the UE is in the service area. When the UE moves to a TA outside the TAI list, it sends a TAU (Tracking Area Update) Request (location registration request) message in which the TA in which the UE is located is set to the MME via the eNB in the TA. To do. As a result, the service area information that the MME holds and indicates the TA in which the UE is in the service area is updated.

In the LTE network, when a user data packet for the UE is generated from an external network such as the Internet, a Downlink Data Notification (downlink data notification) is transmitted from the S-GW to the MME. Upon receiving the downlink data notification, the MME performs paging of the target UE based on the area information of the target UE. Specifically, the MME sends a paging message for paging of the target UE to one or more eNBs according to a predetermined paging policy. In the example of FIG. 12, paging is performed on TA # 1 whose location is registered by the UE.

The eNB that receives the paging message from the MME transmits the paging message into the cell formed by the eNB. As shown in FIG. 12, the paging target UE transmits a service request message from the eNB to the MME via the eNB # 2 that is the source of the paging message in response to the reception of the paging message. As a result, a connection between the UE and eNB # 2 and a connection between eNB # 2 and S-GW are established, and downlink and uplink data transmission via the connection becomes possible.

The above-mentioned paging policy used by MME defines the range (paging area) and frequency (time interval) of paging. The paging policy includes, for example, (1) eNB (Last eNB) in which the UE was most recently located, (2) TA (Last TAI) in which the UE is most recently registered, and (3) TAI list (TAI). -List), and paging can be specified in this order. Alternatively, paging can be performed in the order of (1) Last TAI, (2) TAI-List, and (3) TAI-List (that is, paging to Last TAI is repeated twice after paging to TAI-List). Can be determined.

In the present embodiment, the MME 11 does not control the paging policy for each UE, and the paging process of each UE (that is, the paging message is sent via the S1-MME interface) according to the preset paging policy regardless of the UE. The process of transmitting to one or more eNBs) is performed. On the other hand, the MEC node 10 provided between the eNB and the MME 11 realizes control (adjustment) of the paging policy for each UE.

Specifically, the MEC node 10 adjusts the paging range in the paging of the UE existing in the cells of the plurality of eNBs by analyzing the signaling information transmitted between each of the plurality of eNBs and the MME 11. Gather information to do. The information collected is, for example, at least one of information indicating the movement status of the UE and information indicating the communication status. When the MEC node 10 receives the paging message for paging of the UE sent to one or more eNBs by the MME 11 according to a predetermined paging policy, the MEC node 10 determines the paging range based on the information collected as described above. To do. Further, the MEC node 10 transmits a paging message for paging of the UE to each eNB included in the determined paging range.

In this way, edge computing is used to control the paging process on a UE-by-UE basis. As a result, it is possible to control the paging policy on a UE-by-UE basis without increasing the transaction load associated with the paging process in the MME 11. That is, it becomes possible to control (adjust) the paging policy on a UE-by-UE basis without affecting the operation of the existing movement management device (MME).

In the following, a configuration example of the MEC node for realizing such paging processing and an example of a specific processing procedure in the MEC node will be described.

<MEC node configuration>
FIG. 2 is a block diagram showing a hardware configuration example of the MEC node 10 according to the present embodiment. The MEC node 10 has a CPU 21, a ROM 22, a RAM 23, an external storage device 24 (HDD or the like), and a communication device 25 (communication interface).

In the MEC node 10, for example, a program stored in any one of the ROM 22, the RAM 23, and the external storage device 24 for realizing each function of the MEC node 10 is executed by the CPU 21. The CPU 21 may be replaced by one or more processors such as an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), and a DSP (digital signal processor).

The communication device 25 transfers (receives and transmits) packets transmitted between the MME 11 or S-GW 12 in the EPC and each eNB housed in the MEC node 10 under the control of the CPU 21, and each eNB. Communication with (for example, acquisition of local information from each eNB) can be performed. Further, the communication device 25 can communicate with another adjacent MEC node under the control of the CPU 21. The MEC node 10 may have a plurality of communication devices 25 having different connection destinations.

The MEC node 10 may be provided with dedicated hardware for executing each function, or a part of the MEC node 10 may be executed by the hardware and the other part may be executed by a computer running the program. Also, all functions may be performed by a computer and a program.

FIG. 3 is a block diagram showing a functional configuration example of the MEC node 10 according to the present embodiment. Each function of the MEC node 10 is a logical function realized by the hardware of FIG. 2, for example, and can be realized by the CPU 21 executing a program stored in the ROM 22 or the like. In the present embodiment, the MEC node 10 has a packet transmission / reception unit 31, a flow identification unit 32, a signaling analysis unit 33, a terminal information analysis unit 34, an information management unit 35, and a control unit 36. The MEC node 10 further has a local information acquisition unit 37 for realizing a function of acquiring local information (for example, information indicating a wireless communication status in a cell of each eNB) from each housed eNB. You may be.

The packet transmission / reception unit 31 has a function of receiving a packet transmitted between the eNB and the EPC, and a function of transmitting the packet to the eNB or the EPC. The flow identification unit 32 identifies the flow of the packet received by the packet transmission / reception unit 31. In the present embodiment, the flow identification unit 32 determines that the flow of a series of received packets is a flow of a control packet (S1-MME packet) including signaling information (control information) or a data packet (S1-) containing user data. Identify whether it is a U packet) flow.

The signaling analysis unit 33 analyzes the signaling information included in the packet received from any of the plurality of eNBs and MME 11, the UE (target UE) targeted by the received packet, and the message included in the received packet. Identify the type of. The signaling analysis unit 33 outputs the identification results to the terminal information analysis unit 34.

Further, when the signaling information to be analyzed is encrypted, the signaling analysis unit 33 acquires the encryption information (encryption key) used by the identified target UE from the information management unit 35. Further, the signaling analysis unit 33 decrypts the encrypted signaling information regarding the target UE by using the acquired encryption information.

When the MEC node 10 (information management unit 35) does not hold the encrypted information that can be used for decrypting the encrypted signaling information about the target UE in the analysis of the signaling information, the signaling analysis unit 33 , Notifies the terminal information analysis unit 34 and the control unit 36 that there is no usable encrypted information for the target UE. For example, when the encrypted signaling information cannot be decrypted using the encrypted information of the target UE included in the user information table managed by the information management unit 35, the above notification is performed. In addition, when the encryption information of the target UE is lost due to the deletion of the record corresponding to the target UE (including the encryption information) from the user information table managed by the information management unit 35, The above notification may be given.

Upon receiving the above notification from the signaling analysis unit 33, the control unit 36 acquires the encryption information of the target UE by the reconnection control (FIGS. 10 and 11) described later. The encrypted information may be acquired from another adjacent MEC node by the terminal information analysis unit 34, as will be described later.

The terminal information analysis unit 34 collects information from the message included in the received packet according to the message type identified by the signaling analysis unit 33, and causes the information management unit 35 to hold (manage) the collected information. For example, if the above message is a message related to attachment, location registration, or handover, the terminal information analysis unit 34 collects information indicating the movement status of the target UE from the message. Further, if the above message is a message related to wireless connection or wireless release, the terminal information analysis unit 34 collects information indicating the communication status of the target UE from the message. In the following, a specific example of the processing executed by the MEC node 10 when collecting the movement history of the UE as the information indicating the movement status and the communication history of the UE as the information indicating the communication status will be described.

Further, the terminal information analysis unit 34 has a function of acquiring the encryption information (encryption key) of the target UE identified by the signaling analysis unit 33 from another adjacent MEC node. Specifically, the terminal information analysis unit 34 identifies another MEC node that was accommodated immediately before the target UE was accommodated in the MEC node 10 based on the unencrypted signaling information included in the received packet. Then, the encrypted information is acquired from the specified other node device.

However, depending on the type of message included in the received packet, the MEC node specified based on the signaling information may or may not have the encrypted information. For example, when the message is a message related to location registration or handover that does not involve the movement of the target UE between areas managed by different MMEs, the MEC node specified based on the signaling information is the encrypted information. have. Therefore, in such a case, it is effective to identify another MEC node based on the signaling information and try to acquire the encrypted information.

When the target UE performs a handover from the cell of the eNB accommodated in any MEC node to the cell of the eNB accommodated in the MEC node 10, the target UE is accommodated immediately before. There are no other MEC nodes. That is, there is no other MEC node that should be a contact for inquiries about the encrypted information, and the MEC node 10 cannot acquire the encrypted information from the other MEC node. When the terminal information analysis unit 34 cannot acquire the encrypted information from the other MEC node in this way, the terminal information analysis unit 34 notifies the control unit 36 of that fact. Upon receiving the notification from the terminal information analysis unit 34, the control unit 36 acquires the encrypted information of the target UE by the reconnection control described later.

The information management unit 35 manages base station information, adjacent MEC node information, and user information as illustrated in FIG. 4 to be described later. The information collected by the terminal information analysis unit 34 can be managed by the information management unit 35 as user information. The information management unit 35 manages each information in a state where each information is stored in the RAM 23 or the external storage device 24.

When the paging message is received from the MME 11, the control unit 36 determines the paging range based on the information collected by the terminal information analysis unit 34 and managed by the information management unit 35. Further, the control unit 36 transmits a paging message to each eNB included in the determined paging range. Further, the control unit 36 acquires the encrypted information of the target UE by the reconnection control described later in response to the notification from the signaling analysis unit 33 or the terminal information analysis unit 34.

<Management information of the information management department>
Next, an example of information managed by the information management unit 35 will be described with reference to FIG. As shown in FIG. 4, the information management unit 35 can manage each information in a table format.

FIG. 4A is an example of a base station information table managed by the information management unit 35. The base station information includes the identification information of the base station (eNB), the TAI corresponding to the TA to which each eNB belongs, and the information indicating the MEC node in which each eNB is housed, which is associated with the identification information. .. The base station information is information preset for the MEC node 10 and is used for terminal registration processing and the like described later. The base station information may be updated in response to a change in the network configuration (for example, addition of an eNB accommodated in the MEC node 10 or an adjacent MEC node).

FIG. 4B is an example of an adjacent MEC node information table managed by the information management unit 35. The adjacent MEC node information includes the MME in which each MEC node is housed and the IP address assigned to each MEC node as the information of each MEC node adjacent to the MEC node 10. The adjacent MEC node information is information preset for the MEC node 10 and is used for terminal registration processing and the like described later. The adjacent MEC node information may be updated in response to a change in the network configuration (for example, addition of an adjacent MEC node).

FIG. 4C is an example of a user information table managed by the information management unit 35. The user information table includes encrypted information associated with the terminal ID of the UE and information (history information) collected by the terminal information analysis unit 34 as a record for each wireless terminal (UE). The information held in the user information table corresponds to the information about the UE housed or has been housed in the MEC node 10. The encrypted information is a NAS encryption used for decrypting a NAS (non-access layer) message contained in a control packet received by the packet transmission / reception unit 31 (transmitted / received between the UE and the MME 11 via the eNB). Encryption information (encryption key). The history information includes at least one of the movement history and the communication history of the UE.

Here, NAS is a functional layer in the protocol stack between the UE and MME. The NAS message is transmitted as the payload of the S1AP (application protocol) message between the MME and the eNB, and is transmitted as the payload of the RRC (radio resource control) protocol message between the eNB and the UE. In this way, the NAS message passes through the eNB in a state of being encapsulated by the message of the lower layer. The encryption of the NAS message is performed by the transmitting node (UE or MME) using the NAS encryption information. A flag indicating whether or not the NAS message is encrypted is added to the header portion of the NAS message. Therefore, by referring to the flag, it is possible to identify whether or not the NAS message is encrypted.

The user information table further includes connection bearer information used by the control unit 36 and a reconnection waiting flag as records for each UE. The connection bearer information is information indicating a bearer established for the corresponding UE. In the present embodiment, the E-RAB ID, QCI (QoS Class Identifier) and ARP (Allocation and Retention Priority) used in S1AP are retained as the connection bearer information. QCI and ARP are examples of parameters related to bearer service quality established for UEs. In this way, the information management unit 35 holds the parameters related to the service quality of the bearer established for the UE in the user information table for each UE.

Further, the reconnection waiting flag in the user information table is a state in which the execution of the detach process (S403 in FIG. 10A or S504 in FIG. 10B) for the corresponding UE in the reconnection control described later is suspended. It is a flag indicating whether or not it is. This detaching process is started by transmitting a control signal to the UE, which causes the UE to perform reattachment to the EPC (core network) accompanied by authentication of the UE. In the present embodiment, the control unit 36 suspends execution of the detach processing for the UE to be executed in the detach processing in the reconnection control while a specific bearer such as a bearer for voice communication is established. Then, the detach process is executed after the specific bearer is released.

When the detach processing is executed for the UE in the reconnection control by the control unit 36, the bearer established for the UE is released, and the communication being executed by the UE is temporarily disconnected. However, when communication that requires real-time performance such as voice communication is performed, it is necessary to avoid such disconnection of communication. Therefore, in order to avoid such disconnection of communication due to the detachment process, the control unit 36 has a bearer (for example, QCI = 5 and QCI = 5) corresponding to the parameters defined in the disconnection prohibition table held by the information management unit 35. , ARP = 4 bearer) is not executed while the detaching process is established.

The information management unit 35 uses the unnecessary records in the user information table as described later in order to prevent the records in the user information table from increasing indefinitely and excessively consuming computational resources such as the RAM 23. It may have a function to delete.

<MEC node processing procedure>
FIG. 5 is a flowchart showing a procedure of processing executed by the MEC node 10. At the MEC node 10, each time a packet transmitted between the EPC and the eNB housed in the MEC node 10 is received by the packet transmission / reception unit 31, the process according to the procedure of FIG. 5 is executed. The execution order of the processes of each step shown in FIGS. 5 to 8 and 10 is not limited to the indicated order, and the order can be arbitrarily changed and executed.

First, in S1, when the packet transmission / reception unit 31 receives the packet transmitted from the EPC or eNB, the received packet is output to the flow identification unit 32. Next, in S2, the flow identification unit 32 identifies the flow of the received packet. Specifically, the flow identification unit 32 determines whether or not the received packet is a control packet (S1-MME packet), and if the received packet is a control packet, proceeds to S3. On the other hand, when the received packet is not a control packet (that is, it is an S1-U packet containing user data), the flow identification unit 32 proceeds to S11. In this case, in S11, the packet transmission / reception unit 31 transmits (forwards) the received packet to the original destination specified in the received packet based on the result of the flow identification by the flow identification unit 32, and ends the process. ..

In S3, the signaling analysis unit 33 analyzes the signaling information included in the received packet to identify the UE (target UE) targeted by the received packet and the type of message included in the received packet. The signaling analysis unit 33 outputs the identification results to the terminal information analysis unit 34. The signaling analysis unit 33 uses the encrypted information when the information management unit 35 manages the encrypted information necessary for analyzing the encrypted signaling information.

Next, in S4, the terminal information analysis unit 34 holds the information (encrypted information and history information in FIG. 4C) associated with the identified target UE in the user information table by the information management unit 35. Determine if it is (managed). The terminal information analysis unit 34 proceeds to S5 when the correspondence information of the target UE is not held, and proceeds to S7 when it is held. If only the terminal ID of the target UE and the reconnection waiting flag are held in the user information table, the terminal information analysis unit 34 determines that the corresponding information is not held, and processes S5. Proceed.

In S5, the terminal information analysis unit 34 determines whether or not the reconnection waiting flag corresponding to the target UE is set to ON, and if it is set to ON, proceeds to the process to S10. In this case, even if the terminal information analysis unit 34 receives a packet from either the eNB or the MME 11 while the specific bearer is established for the target UE, the terminal information analysis unit 34 goes to another node device (adjacent MEC node). It operates so as not to inquire about the encrypted information (do not execute the process of S106 in FIG. 6). As a result, the terminal information analysis unit 34 executes (repeats) inquiries about the encryption information to other MEC nodes until the encryption information of the target UE is acquired by the reconnection control (FIG. 10B) described later. Can be suppressed. That is, it is possible to suppress the occurrence of unnecessary processing by repeating the inquiry of the encrypted information to the other MEC node every time the control packet is received.

In S5, the terminal information analysis unit 34 proceeds to S6 when the reconnection waiting flag is set to OFF. In S6, the terminal information analysis unit 34 executes the terminal registration process for the target UE according to the procedure shown in FIG. When the process of S6 is completed, the terminal information analysis unit 34 advances the process to S10.

On the other hand, in S7, the terminal information analysis unit 34 determines whether or not the fraud of the encrypted information of the target UE managed by the information management unit 35 is detected based on the notification from the signaling analysis unit 33. .. When the terminal information analysis unit 34 is notified that the encrypted signaling information cannot be correctly decrypted using the encryption information of the target UE (there is no available encryption information for the target UE), the terminal information analysis unit 34 is notified. , It is determined that the invalidity of the encrypted information of the target UE has been detected, and the process proceeds to S9. In this case, in S9, the control unit 36 executes reconnection control for the target UE according to the procedure shown in FIG. 10 (A).

If it is determined in S7 that the illegality of the encrypted information of the target UE is not detected, the terminal information analysis unit 34 proceeds to S8. In S8, the terminal information analysis unit 34 executes the information update process for the target UE according to the procedure shown in FIG. When the process of S8 is completed, the terminal information analysis unit 34 advances the process to S10.

When the terminal registration process (S6) or information update process (S8) is completed, when the reconnection wait flag is set to ON (“YES” in S5), or the process according to the procedure shown in FIG. 10 (A). When the above is completed, in S10, the control unit 36 determines whether or not the type of the message included in the received packet is paging based on the identification result by the signaling analysis unit 33. If the message type is not paging, the control unit 36 proceeds to S11. In this case, in S11, the packet transmission / reception unit 31 transmits (forwards) the received packet to the original destination specified in the received packet, and ends the process. On the other hand, when the message type is handover, the control unit 36 proceeds to S12 and executes paging control according to the procedure shown in FIG. After the paging control is completed, the control unit 36 ends the process according to the procedure of FIG.

<Terminal registration process>
Next, the procedure of the terminal registration process (S6) will be described with reference to FIG. The terminal registration process is a process of accommodating (registering) the target UE in the MEC node 10 by registering the information of the target UE in the user information managed by the information management unit 35.

First, in S101 to S104, the terminal information analysis unit 34 determines the type of the message included in the received packet based on the identification result by the signaling analysis unit 33, and executes processing according to the determined type. Specifically, the terminal information analysis unit 34 has a message type of any one of IMSI (International Mobile Subscriber Identity) attach, GUTI (Globally. Unique Temporary Identifier) attach, X2 handover, S1 handover, and location registration. Is determined. When the message type is neither of these types, the terminal information analysis unit 34 ends the terminal registration process without performing the process based on the received packet.

(IMSI Attach)
When the message type is the IMSI attach (“YES” in S101), the terminal information analysis unit 34 proceeds to the process to S110. The IMSI attach and the GUTI attach described later are based on an Attach Request message sent to the MME 11 via the eNB in order for the UE to newly connect to the network (register the UE in the network) when the power of the UE is turned on. Can be identified. In particular, since the IMSI attach request is made when the UE is registered in the network for the first time, the information of the UE is not held in the adjacent MEC node. Therefore, the terminal information analysis unit 34 proceeds to S110 without performing the processing of S106.

The IMSI attach corresponds to the attachment accompanied by the authentication of the UE (wireless terminal). When the IMSI attach is performed, in S110, the encrypted information of the target UE can be acquired from the signaling information included in the received packet and stored in the user information table managed by the information management unit 35.

(GUTI Attach)
When the message type is GUTI attach (“YES” in S102), the terminal information analysis unit 34 proceeds to S106. The encrypted information of the target UE that made the GUTI attach request may be held by the adjacent MEC node. Therefore, in S106, the terminal information analysis unit 34 attempts to acquire the encryption information of the target UE from the adjacent MEC node by inquiring the adjacent MEC node about the encryption information of the target UE.

Specifically, the terminal information analysis unit 34 refers to the "Last visited registered TAI" element in the Attach Request message, and acquires the TAI corresponding to the TA in which the target UE was immediately (last) in the service area. .. Further, the terminal information analysis unit 34 uses the accommodating MEC node associated with the acquired TAI based on the base station information managed by the information management unit 35 as the MEC node in which the target UE was immediately accommodated. Identify and make an inquiry to the MEC node. Further, when the target UE cannot acquire the TAI corresponding to the TA that was in the service area immediately before, the terminal information analysis unit 34 is based on the GUTI stored in the "Additional GUTI" element in the Attach Request message. , Guess that the target UE is one or more MEC nodes that were previously housed. Further, the terminal information analysis unit 34 makes an inquiry to each estimated MEC node. After that, the terminal information analysis unit 34 proceeds to S107.

(X2 handover)
When the message type is X2 handover (“YES” in S103), the terminal information analysis unit 34 proceeds to S106. The X2 handover is a handover performed between eNBs belonging to the same MME 11. In the X2 handover, a control message is transmitted and received between the handover source eNB and the handover destination eNB via the X2 interface, and a Path Switch Request message is transmitted from the handover destination eNB to the MME 11. .. The X2 handover can be identified based on this Path Switch Request message.

In S106, the terminal information analysis unit 34 attempts to acquire the encrypted information of the target UE from the adjacent MEC node as described above. Specifically, when the terminal information analysis unit 34 contains information in the "Source MME GUMMEI" element in the Path Switch Request message, the target UE is finally accommodated based on the information. Identify the MME. Further, the terminal information analysis unit 34 is one in which the target UE has immediately accommodated the accommodating MEC node associated with the specified MME based on the adjacent MEC node information managed by the information management unit 35. Estimate as the above MEC node. The terminal information analysis unit 34 makes an inquiry to each of the estimated MEC nodes. On the other hand, if the "Source MME GUMMEI" element in the Path Switch Request message does not contain any information, the terminal information analysis unit 34 uses all the information based on the adjacent MEC node information managed by the information management unit 35. Make an inquiry to the adjacent MEC node of. After that, the terminal information analysis unit 34 proceeds to S107.

(Location registration or S1 handover)
When the message type is location registration or S1 handover (“YES” in S104), the terminal information analysis unit 34 proceeds to S105. The location registration can be identified from the UE to the MME 11 based on a TAU Request message, and the S1 handover can be identified based on a Handover Request message transmitted from the MME 11 to the handover destination eNB. In S105, the terminal information analysis unit 34 determines whether or not the location registration or S1 handover is accompanied by the movement between the MMEs of the target UE, and if it is accompanied, the process proceeds to S110, and if it is not accompanied. To proceed to S106. When the location registration or the S1 handover is accompanied by the movement between the MMEs of the target UE, the encryption information of the target UE is obtained from the signaling information exchanged between the target UE and the new connection destination MME in S110. Can be acquired and stored in the user information table managed by the information management unit 35.

When location registration or S1 handover without movement between MMEs is performed, there is a possibility that the encryption information of the target UE can be acquired from the MEC node in which the target UE is housed immediately before. Therefore, in S106, the terminal information analysis unit 34 attempts to acquire the encrypted information of the target UE from the adjacent MEC node as described above.

Specifically, when the message type is location registration, the terminal information analysis unit 34 refers to the "Last visited registered TAI" element in the TAU Request message, and the target UE was immediately (last) in the service area. Acquire the TAI corresponding to the TA. Further, the terminal information analysis unit 34 uses the accommodating MEC node associated with the acquired TAI based on the base station information managed by the information management unit 35 as the MEC node in which the target UE was immediately accommodated. Identify and make an inquiry to the MEC node. Further, when the target UE cannot acquire the TAI corresponding to the TA that was in the service area immediately before, the terminal information analysis unit 34 is based on the GUTI stored in the "Old GUTI" element in the TAU Request message. , Guess that the target UE is one or more MEC nodes that were previously housed. Further, the terminal information analysis unit 34 makes an inquiry to each estimated MEC node. After that, the terminal information analysis unit 34 proceeds to S107.

Further, when the message type is S1 handover, the terminal information analysis unit 34 refers to "Last Visited Cell Information" included in the "Source eNB to Target eNB Transparent Container" element in the Handover Request message, and the target UE is immediately before. The ECGI (E-UTRAN Cell Global Identifier) corresponding to the eNB housed in is acquired. Further, the terminal information analysis unit 34 identifies the MEC node in which the eNB indicated by the acquired ECGI is housed based on the base station information managed by the information management unit 35, and makes an inquiry to the MEC node. Do. After that, the terminal information analysis unit 34 proceeds to S107.

In S107, the terminal information analysis unit 34 determines in S106 whether or not the acquisition of the encrypted information of the target UE from the adjacent MEC node is successful, and if so, proceeds to S110. In S110, the terminal information analysis unit 34 stores the information collected from the signaling information included in the received packet in the user information table managed by the information management unit 35. Further, when the terminal information analysis unit 34 succeeds in acquiring the encrypted information from the adjacent MEC node in S106, the terminal information analysis unit 34 saves the acquired encrypted information in the user information management table. After that, the terminal information analysis unit 34 starts collecting the movement history and the communication history of the target UE in S110, and ends the terminal registration process. The movement history and communication history can be acquired according to the message type of the received packet, as will be described later with reference to FIG. 7.

On the other hand, when the terminal information analysis unit 34 fails to acquire the encrypted information of the target UE from the adjacent MEC node in S106, the terminal information analysis unit 34 proceeds from S107 to S108. When the terminal information analysis unit 34 cannot acquire the encrypted information of the target UE from the adjacent MEC node, the terminal information analysis unit 34 saves the terminal ID of the target UE in the user information table managed by the information management unit 35 in S108. Proceed to process to S109. In S109, the control unit 36 executes reconnection control for the target UE according to the procedure shown in FIG. 10 (A).

<Information update process>
Next, the procedure of the information update process (S8) will be described with reference to FIG. 7. The information update process is a process of updating the movement history or communication history of the target UE, which is managed as user information by the information management unit 35 based on the received packet.

First, in S201 to S202, the terminal information analysis unit 34 determines the type of the message included in the received packet, and executes processing according to the determined type. Specifically, the terminal information analysis unit 34 determines whether the message type is any of wireless connection, wireless release, X2 handover, S1 handover, and location registration. When the message type is neither of these types, the terminal information analysis unit 34 ends the information update process without performing the process based on the received packet.

(Wireless connection or release)
When the message type is wireless connection or release (“YES” in S201), the terminal information analysis unit 34 proceeds to S203. The wireless connection is identified, for example, based on the Initial UE Message, which is an S1AP message transmitted from the eNB to the MME 11. The Initial UE Message is a message for establishing an S1 connection between the eNB and the MME 11. Further, the radio release is specified based on, for example, a UE Context Release Request which is a message of S1AP transmitted from the eNB to the MME 11. The UE Context Release Request is a message for disconnecting the S1 connection between the eNB and the MME 11.

In S203, the terminal information analysis unit 34 communicates with the UE in the user information table managed by the information management unit 35 based on the content and generation time of the message included in the packet received by the packet transmission / reception unit 31. Update history. For example, the terminal information analysis unit 34 can save the start time of communication by the UE in the communication history according to the wireless connection, and save the end time of the communication by the UE in the communication history according to the wireless release. The terminal information analysis unit 34 can include the content of the communication in the communication history by analyzing other messages transmitted between the eNB and the MME 11. When the update of the communication history is completed, the terminal information analysis unit 34 ends the information update process.

(X2 handover, S1 handover or location registration)
When the message type is X2 handover, S1 handover, or location registration (“YES” in S202), the terminal information analysis unit 34 proceeds to S204. In S204, the terminal information analysis unit 34 moves the UE in the user information table managed by the information management unit 35 based on the content and generation time of the message included in the packet received by the packet transmission / reception unit 31. Update history. For example, the terminal information analysis unit 34 acquires information (ID, etc.) indicating eNB corresponding to the cell of the handover source and the cell of the handover destination as position information from the received packet, and records the movement history together with the occurrence time of the received packet. Can be saved. Further, the terminal information analysis unit 34 acquires the TAI corresponding to the TA for which the UE registers the position from the received packet as the position information, and saves it in the movement history together with the occurrence time of the received packet. When the update of the movement history is completed, the terminal information analysis unit 34 ends the information update process.

Although not shown in the example of FIG. 7, when the terminal information analysis unit 34 receives the packet including the Attach Request message, the movement history may be updated based on the content and the occurrence time of the message. ..

<Paging control>
Next, the procedure of the paging control (S12) will be described with reference to FIG. When the control unit 36 receives the paging message for paging of the target UE transmitted to one or more eNBs according to the predetermined paging policy by the MME 11, the control unit 36 starts the paging control by the procedure shown in FIG. The paging control is executed to control the paging process for the target UE, which is started by the MME 11.

First, in S301, the control unit 36 sets the paging message as a transmission target based on the history information (at least one of the movement history and the communication history) of the target UE in the user information table managed by the information management unit 35. Determines a paging range that includes one or more eNBs. For example, the movement direction or the position of the movement destination of the UE may be predicted based on the movement history and the communication history, and the eNB in the vicinity of the position along the movement direction or the position of the movement destination may be included in the paging range. Alternatively, if the terminal information analysis unit 34 collects the paging success rate of the target UE as the communication history, the control unit 36 may determine the paging range based on the paging success rate.

Next, in S302, the control unit 36 transmits a paging message for paging of the target UE to each eNB within the paging range determined in S301, and ends the process. If the paging fails, the control unit 36 may repeat the transmission of the paging message a plurality of times. In that case, the control unit 36 may transmit the paging message to all the eNBs in the TAI list (TAI-List) assigned to the target UE in one transmission out of the plurality of transmissions. As a result, by adjusting the paging range by the control unit 36, even if the eNB in which the target UE is located leaks from the paging range, paging can be successful.

FIG. 9 is a diagram showing a specific example of the above-mentioned paging control. 9 (A) and 9 (B) show an example in which the paging range according to the paging policy in MME 11 is expanded in MEC node 10. Further, FIG. 9C shows an example in which the paging range according to the paging policy in the MME 11 is narrowed in the MEC node 10.

In the example of FIG. 9A, it is assumed that the UE is an in-vehicle terminal or the like and continues to move in TA # 1 at a certain speed. In this example, the MME 11 transmits a paging message to the Last eNB (eNB # 1 in this example) about the paging target UE (target UE) according to a preset paging policy. On the other hand, the MEC node 10 determines the paging range to the wider Last TA (TA # 1 in this example) based on the movement history and communication history of the target UE, and eNB # included in TA # 1. A paging message is being sent to 1 and eNB # 2. That is, the MEC node 10 adjusts the paging range by the MME 11 to a wider range and transmits the paging message. The MEC node 10 may determine the paging range to be a TAI-List wider than the Last TA.

In the example of FIG. 9B, it is assumed that the UE frequently moves near the cell boundary of the adjacent eNB # 2 and eNB # 3. In this example, as in the example of FIG. 9A, the MME 11 sends a paging message to the Last eNB (eNB # 1 in this example) for the paging target UE (target UE) according to the preset paging policy. I'm sending. On the other hand, the MEC node 10 determines the paging range to a wider TAI-List (TA # 1 and TA # 2 in this example) based on the movement history and communication history of the target UE, and TAI- A paging message is sent to eNB # 1, eNB # 2, eNB # 3 and eNB # 4 in the List. That is, the MEC node 10 adjusts the paging range by the MME 11 to a wider range and transmits the paging message.

In the example of FIG. 9C, it is assumed that the UE is a stationary IoT terminal or the like and the UE continues to be substantially stationary in the cell of eNB # 2. In this example, the MME 11 sends a paging message to the LAST TA (TA # 1 in this example) about the UE (target UE) to be paging according to a preset paging policy. On the other hand, the MEC node 10 determines the paging range to the narrower Last eNB (eNB # 2 in this example) based on the movement history and communication history of the target UE, and transmits a paging message to the eNB # 2. doing. That is, the MEC node 10 adjusts the paging range by the MME 11 to a narrower range and transmits the paging message.

<Reconnection control (when receiving packets)>
Next, the procedure of the reconnection control (S9 or S109) executed when the packet is received will be described with reference to FIG. 10A.

In S401, the control unit 36 determines whether or not a bearer (specific bearer) registered in the disconnection prohibition table (FIG. 4 (D)) managed by the information management unit 35 is established for the target UE. To judge. This determination is made based on the connection bearer information held in the user information table. When the control unit 36 determines that the bearer registered in the disconnection prohibition table has not been established for the target UE, the control unit 36 proceeds to S402, and when it determines that it has been established, the control unit 36 proceeds to S404.

In S404, the control unit 36 sets the reconnection waiting flag to ON and proceeds to the process to S10 (FIG. 5). In this way, the control unit 36 keeps setting the reconnection waiting flag to ON while the bearer registered in the disconnection prohibition table is established for the target UE, and the detach processing (EPC) for the UE is performed. It operates without performing a control signal transmission that causes the UE to reattach to.

On the other hand, in S402, the control unit 36 sets the reconnection flag to OFF and proceeds to S403. In S403, the control unit 36 acquires the encryption information of the target UE by starting the detach processing for the target UE. After that, the control unit 36 proceeds to S10 (FIG. 5).

FIG. 11 is a diagram showing a communication sequence related to acquisition of encrypted information by the above-mentioned reconnection control. When the detach processing in S403 is started, the MEC node 10 acquires the encryption information of the target UE according to the communication sequence shown in FIG.

When the MEC node 10 starts the detach processing for the target UE (S601), the MEC node 10 transmits a control signal including the UE Context Release Command, which is a message of S1AP, to the eNB (S602). Upon receiving the control signal, the eNB transmits a control signal including the RRC Connection Release, which is a message of the RRC protocol, to the target UE (S603). The control signals of S602 and S603 include information indicating detachment from the EPC side. In the present embodiment, this control signal corresponds to a disconnection signal for detach processing for the target UE. As described below, the MEC node 10 acquires the encryption information of the target UE in the connection process performed from the target UE to the MME 11 in response to the reception of the disconnection signal.

When the target UE detects the detachment from the EPC side by the control signal received from the eNB (S604), the target UE starts executing the reattachment to the EPC in response to the reception of the control signal (S605). First, the target UE transmits a control signal (first request signal) including an Attach Request, which is a NAS message, to the MME 11 via the eNB (S606). This control signal includes a control packet for a GUTI attach, which is an attach (reattach) without authentication of the UE.

The MEC node 10 terminates the control signal including the Attach Request received from the eNB at the MEC node 10 without transferring it to the MME 11, and responds to the target UE to prompt the IMSI attach (S607). Specifically, the MEC node 10 transmits a control signal (attach rejection signal) including an Attach Reject which is a NAS message to the target UE (S608). This control signal includes information indicating that the EPC cannot specify the ID of the UE as information for prompting the target UE to attach the IMSI.

In response to the reception of the control signal including the Attach Reject described above, the target UE transmits the control signal (second request signal) including the Attach Request, which is a NAS message, to the MME 11 via the eNB (S609). This control signal includes a control packet for the IMSI attach, which is an attach (reattach) with authentication of the UE. When the MEC node 10 receives the control signal including the Attach Request from the target UE via the eNB, the MEC node 10 transfers the control signal to the MME 11.

After that, the signaling information for the new connection processing of the target UE to the EPC is transmitted between the target UE and the MME 11 (S610). In this way, the MEC node 10 acquires the encryption information of the target UE from the signaling information transmitted between the target UE and the MME 11 in the new connection process started by the control signal (S609) including the Attach Request. ..

<Reconnection control (when bearer release is detected)>
Next, with reference to FIG. 10B, the procedure of reconnection control executed when the bearer release is detected will be described. In the MEC node 10, the control unit 36 follows the procedure shown in FIG. 10B each time it detects that the bearer established for any UE registered in the user information table has been released. Perform reconnection control.

In S501, the control unit 36 determines whether or not the reconnection waiting flag corresponding to the UE (target UE) using the released bearer is set to ON, and if it is set to OFF. Ends the process, and if it is set to ON, proceeds to the process to S502.

In S502, similarly to S401, the control unit 36 establishes a bearer (specific bearer) registered in the disconnection prohibition table (FIG. 4D) managed by the information management unit 35 for the target UE. Judge whether or not. When the control unit 36 determines that the bearer registered in the disconnection prohibition table has not been established for the target UE, the control unit 36 proceeds to S503, and when it determines that the bearer has been established, the control unit 36 ends the process.

In S503, the control unit 36 sets the reconnection flag to OFF and proceeds to S504. In S504, the control unit 36 acquires the encryption information of the target UE by starting the detach processing for the target UE, as in S403, and ends the processing. When the detachment process in S504 is started, the MEC node 10 acquires the encryption information of the target UE according to the communication sequence shown in FIG. 11 as described above.

As described above, the control unit 36 does not perform the detach processing on the target UE while the specific bearer is established for the target UE (“YES” in S503). The control unit 36 controls the UE to perform detach processing (reattach to the EPC) after the specific bearer established for the target UE is released (“NO” in S503). Signal transmission) (S504). As a result, it is possible to prevent the target UE from being disconnected due to the detachment process for the UE while the target UE is performing communication requiring real-time performance such as voice communication. That is, even if a temporary disconnection of communication occurs, the detach processing can be executed at a safer timing with less influence on the target UE.

As described above, the MEC node 10 of the present embodiment exists in the cells of the plurality of eNBs by analyzing the signaling information included in the packet transmitted between each of the plurality of eNBs and the MME 11. Gather information to adjust the paging range of the UE. When the MEC node 10 does not hold the encrypted information that can be used to decrypt the encrypted signaling information about the target UE in the analysis, the MEC node 10 executes the reattachment to the EPC with the authentication of the target UE to the target UE. The control signal to be made is transmitted to the target UE. Further, the MEC node 10 acquires the encryption information of the target UE from the signaling information transmitted between the target UE and the MME 11 in the connection process for reattachment.

According to the present embodiment, the MEC node 10 that controls the paging process for each UE can appropriately acquire the encrypted information necessary for analyzing the encrypted signaling information. Therefore, for example, until the UE performs a handover accompanied by movement between MMEs, the state in which the encrypted information cannot be acquired from the signaling information related to the UE continues, and the MEC node 10 performs the paging process for each UE. It is possible to prevent loss of control.

As a result, the MEC node 10 analyzes the signaling information transmitted between the UE or eNB and the MME 11 using the acquired encrypted information, and controls the paging process on a UE-by-UE basis based on the collected information. Will be possible. That is, the paging policy can be controlled on a UE-by-UE basis without increasing the transaction load associated with the paging process in the MME 11. That is, it becomes possible to control (adjust) the paging policy on a UE-by-UE basis without affecting the operation of the existing movement management device (MME).

Further, the MEC node 10 of the present embodiment transmits a control signal for causing the target UE to reattach to the EPC accompanied by authentication of the target UE in a state where a specific bearer has not been established for the target UE. As a result, the MEC node 10 can acquire the encrypted information of the target UE at a more secure timing with less influence on the target UE even if a temporary disconnection of communication occurs.

<Delete record in user information table>
The above embodiments can be modified in various ways. For example, the information management unit 35 has a function of deleting unnecessary records in the user information table in order to avoid an unlimited increase in records in the user information table and excessive consumption of computational resources such as RAM 23. May have.

For example, the information management unit 35 responds to an inquiry from the other MEC node after the UE housed in the MEC node 10 has handed over to the cell of the eNB connected to the other MEC node. When the encrypted information to be used is provided to the other MEC node, the record corresponding to the UE may be deleted from the user information table. In addition, the information management unit 35 may delete the record corresponding to the UE that has not communicated for a predetermined time from the user information table. This predetermined time may be set to be larger than the timeout value (for example, about 30 minutes) of the Periodic TAU Timer or the Purge Timer, which is the setting value of the LTE system, for example.

By appropriately deleting the records in the user information table in this way, it is possible to prevent the number of records in the user information table from increasing indefinitely, and it is possible to prevent excessive consumption of computational resources such as the RAM 23.

<Other Embodiments>
As shown in FIG. 3, the MEC node 10 may have a local information acquisition unit 37. The local information acquisition unit 37 has a function of acquiring information indicating the wireless communication status in the cell of each eNB housed in the MEC node 10 from each eNB as local information. In this case, when the paging message is received from the MME 11, the control unit 36 determines the paging range based on the local information collected by the terminal information analysis unit 34. Alternatively, the control unit 36 may determine the paging range based on both the information managed by the information management unit 35 and the local information. Further, the control unit 36 transmits a paging message to each eNB included in the determined paging range. By such processing, the paging policy can be adjusted by the MEC node 10 based on the local situation in the cell of each eNB.

The MEC node (management device) according to the present embodiment can be realized by a computer program for making a computer function as a MEC node. The computer program is stored in a computer-readable storage medium and can be distributed, or can be distributed via a network.

10: MEC node (node device)
11: MME (movement management device), 12: S-GW (gateway device)
21: CPU, 22: ROM, 23: RAM, 24: External storage device, 25: Communication device 31: Packet transmission / reception unit, 32: Flow identification unit, 33: Signaling analysis unit 34: Terminal information analysis unit, 35: Information management Unit, 36: Paging control unit 37: Local information acquisition unit

Claims (19)

A node device for edge computing that is placed between multiple base stations and mobile management devices in the core network.
By analyzing the signaling information contained in the packet transmitted between each of the plurality of base stations and the movement management device, the paging range in the paging of the wireless terminal existing in the cells of the plurality of base stations can be determined. Analytical means to collect information for adjustment and
When the node device does not hold the encrypted information that can be used to decrypt the encrypted signaling information about the wireless terminal in the analysis by the analysis means, the core network accompanied by the authentication of the wireless terminal A control means for transmitting a control signal for causing the wireless terminal to reattach the above to the wireless terminal, and
An acquisition means for acquiring the encryption information from the signaling information transmitted between the wireless terminal and the movement management device in the connection process for the reattachment.
A node device characterized by comprising. The node device according to claim 1, wherein the control means transmits the control signal to the wireless terminal in a state where a specific bearer has not been established for the wireless terminal. Further provided with a holding means for holding the parameters related to the service quality of the bearer established for the wireless terminal for each wireless terminal.
The node device according to claim 2, wherein the control means transmits the control signal to the wireless terminal in a state where a bearer corresponding to a predetermined parameter has not been established. The control means does not transmit the control signal to the wireless terminal while the specific bearer is established for the wireless terminal, and after the specific bearer is released, the control means to the wireless terminal. The node device according to claim 2 or 3, wherein a control signal is transmitted. The node device according to any one of claims 2 to 4, wherein the specific bearer includes a bearer for voice communication. The control signal is a disconnection signal for detach processing for the wireless terminal, and is
Any of claims 1 to 5, wherein the acquisition means acquires the encrypted information in the connection process performed from the wireless terminal to the mobile management device in response to the reception of the disconnection signal. The node device according to item 1. The control means
When the first request signal for reattachment without authentication of the wireless terminal, which is transmitted from the wireless terminal to the movement management device in response to the reception of the disconnection signal, is received, the first request signal is moved. The attach rejection signal is transmitted to the wireless terminal without being transferred to the management device.
When a second request signal for reattachment accompanied by authentication of the wireless terminal, which is transmitted from the wireless terminal to the movement management device in response to the reception of the attach rejection signal, is received, the second request signal is moved. The node device according to claim 6, wherein the node device is transferred to a management device. The claim means that the acquisition means acquires the encrypted information from the signaling information transmitted between the wireless terminal and the mobile management device in the connection process started by the second request signal. Item 7. The node device according to item 7. The node device is capable of communicating with other adjacent node devices and
The analysis means inquires of the other node device for the encryption information corresponding to the wireless terminal, and then inquires about the encryption information.
Any one of claims 1 to 8, wherein the control means transmits the control signal to the wireless terminal when the encryption information cannot be acquired from the other node device by the inquiry. The node device described in the section. Based on the unencrypted signaling information, the analysis means identifies another node device that was accommodated immediately before the wireless terminal is accommodated in the node device, and refers to the identified other node device. The node device according to claim 9, further comprising inquiring about the encrypted information. The control means transmits the control signal to the wireless terminal in a state where a specific bearer has not been established for the wireless terminal.
Even if the analysis means receives a packet from any of the plurality of base stations and the mobile management device while a specific bearer is established for the wireless terminal, the analysis means sends the packet to the other node device. The node device according to claim 9 or 10, wherein the node device operates so as not to make an inquiry. As a record for each wireless terminal, a table that holds the encrypted information corresponding to the wireless terminal and the information collected by the analysis means.
After the wireless terminal has handed over to the cell of the base station connected to the other node device, the encryption information corresponding to the wireless terminal is provided to the other node device in response to an inquiry from the other node device. The node device according to any one of claims 1 to 11, further comprising a deletion means for deleting a record corresponding to the wireless terminal from the table. As a record for each wireless terminal, a table that holds the encrypted information corresponding to the wireless terminal and the information collected by the analysis means.
The node device according to any one of claims 1 to 11, further comprising a deletion means for deleting a record corresponding to a wireless terminal that has not communicated for a predetermined time from the table. The control means encrypts the case where the node device does not hold the encryption information corresponding to the wireless terminal, or uses the encryption information held by the node device in association with the wireless terminal. The node device according to any one of claims 1 to 13, wherein the control signal is transmitted to the wireless terminal when the converted signaling information cannot be decoded. Upon receiving a paging message for paging of the wireless terminal transmitted by the mobile management device to one or more base stations in accordance with a predetermined paging policy, the paging range is based on the information collected by the analysis means. And the decision-making means to decide
One of claims 1 to 14, further comprising a transmission means for transmitting a paging message for paging of the wireless terminal to each base station included in the paging range determined by the determination means. The node device according to item 1. The analysis means analyzes the signaling information included in the packet received from any of the plurality of base stations and the movement management device, identifies the type of the message included in the packet, and responds to the identified type. The node device according to claim 15, wherein information is collected from the message. The analysis means
If the message is a message related to attachment, location registration, or handover, information indicating the movement status of the wireless terminal is collected from the message.
The node device according to claim 16, wherein if the message is a message related to wireless connection or wireless release, information indicating a communication status of the wireless terminal is collected from the message. A method of controlling node devices for edge computing, which is placed between multiple base stations and mobile management devices in the core network.
By analyzing the signaling information contained in the packet transmitted between each of the plurality of base stations and the movement management device, the paging range in the paging of the wireless terminal existing in the cells of the plurality of base stations can be determined. The process of collecting information for adjustment and
When the node device does not hold the encrypted information that can be used to decrypt the encrypted signaling information about the wireless terminal in the analysis, it is reattached to the core network with the authentication of the wireless terminal. To the wireless terminal, a step of transmitting a control signal for causing the wireless terminal to execute
A step of acquiring the encrypted information from the signaling information transmitted between the wireless terminal and the mobile management device in the connection process for the reattachment.
A method of controlling a node device, which comprises. A program for causing a computer to execute each step of the control method of the node device according to claim 18.

Images