JP2021057788A - Communication system and communication control method - Google Patents

Abstract

To provide a communication system capable of improving communication efficiency between terminals subordinate to an identical base station while suppressing impediment of communication other than between the terminals subordinate to the identical base station.SOLUTION: In a communication system conforming to LTE communication system, a base station device keeps, as attribute information for establishing a bearer between a core network device and each terminal, first information for identifying a network outside of the core network device of the bearer and second information indicating an IP address of the terminal of the bearer. The base station device determines whether an IP packet received from the first terminal coincides with information identifying the network outside of the core network device of the bearer and the first information kept by the base station device, and whether the IP address contained in the IP packet coincides with the second information kept by the base station device. When the first information and the second information coincide, the base station device transmits the IP packet from a first terminal to a second terminal by using a bearer specified by the first and second information.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to communication systems and communication control methods.

Conventionally, in order to improve communication efficiency in a wireless communication system, LGW (Local GateWay) may be used as a method of returning communication between terminals at a base station. As a prior art of this kind, a wireless communication system including a wireless communication device to which a pair of wireless terminals for communicating packets is connected and a higher-level device of the wireless communication device is known. In this wireless communication system, the host device notifies the wireless communication device of information indicating the pair of wireless terminals in a format that can be identified by the wireless communication device, and the wireless communication device uses the notified information to notify the pair of wireless terminals. A packet received from one of them is returned to the other of the pair of wireless communication terminals (see Patent Document 1).

International Publication No. 2017/026074

The present disclosure provides a communication system and a communication control method capable of improving communication efficiency between terminals under the same base station device while suppressing obstruction of communication between terminals under the same base station device. To do.

One aspect of the present disclosure is a communication system that communicates according to an LTE communication method and includes a base station apparatus and a core network apparatus, wherein the base station apparatus is connected to the core network apparatus and the base station apparatus. Attribute information for establishing a bearer with a terminal is held, and the attribute information includes first information for identifying an external network on the core network device side in the bearer and an IP address of the terminal in the bearer. The core network device establishes a bearer with a terminal connected to the base station device, and the base station device receives an IP packet from the first terminal. Then, it is determined whether or not the information identifying the external network on the core network device side of the bearer to which the IP packet is transmitted and the first information held by the base station device match. It is determined whether or not the IP address included in the IP packet and the second information held by the base station apparatus match, the first information matches, and the second information matches. If they match, the IP packet is sent from the first terminal to the second terminal, which is a terminal device on the terminal side of the bearer, using the bearer specified by the first information and the second information. It is a communication system that transmits and performs return communication.

One aspect of the present disclosure is a communication control method in a communication system including a base station device and a core network device that communicates according to an LTE communication method, wherein the base station device is attached to the core network device and the base station device. Attribute information for establishing a bearer with each connected terminal is held, and the attribute information includes first information for identifying an external network on the core network device side in the bearer, and the attribute information in the bearer. A step of establishing a bearer between the core network device and the terminal connected to the base station device, including a second piece of information indicating the IP address of the terminal, and receiving an IP packet from the first terminal. A step of determining whether or not the step, the information identifying the external network on the core network device side of the bearer to which the IP packet is transmitted, and the first information held by the base station device match. The step of determining whether or not the IP address included in the IP packet and the second information held by the base station apparatus match, and the first information match and said. When the second information matches, the second terminal, which is a terminal device on the terminal side of the bearer from the first terminal, uses the bearer specified by the first information and the second information. It is a communication control method including a step of transmitting the IP packet to and performing return communication.

According to the present disclosure, a communication system and a communication control method capable of improving communication efficiency between terminals under the same base station device while suppressing obstruction of communication other than between terminals under the same base station device. I will provide a.

Block diagram showing a configuration example of a communication system according to an embodiment Diagram showing an example of a table that holds attribute information about bearers Sequence diagram showing an operation example of a communication system The figure which shows an example of the table which holds the permission / denial information of return communication. Block diagram showing the configuration of a communication system including a conventional LGW

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

(Background to obtain one form of this disclosure)
In the LTE (Long Term Evoluation) network, a UE (User Equipment) as a wireless terminal connected to an eNB (eNodeB) as a base station device, a PGW (Packet Data Network Gateway) as an EPC (Evolved Packet Core) device, and the like. A communication path (bearer) via the base station device is installed between the two. The PGW serves as a gateway between the LTE network and the external network. In the LTE network, when trying to communicate from the first terminal to the second terminal under the same base station device, the IP packet is sent to the first terminal, the base station device, the PGW of the EPC device, the base station device, the second terminal, It is relayed in the order of. Therefore, the IP packet reciprocates between the same base station device and the PGW, resulting in low communication efficiency (see FIG. 5).

As shown in Patent Document 1, when the LGW is arranged, the LGW is connected to the base station apparatus (see FIG. 5). The LGW establishes a bearer between the wireless terminal connected to the base station device and the LGW via the base station device (see FIG. 5), and manages communication between the terminals under the same base station device. That is, normally, the LGW manages the LTE (Long Term Evoluation) network performed by the PGW (Packet Data Network Gateway). On the other hand, LGW does not have a function of managing communication other than between terminals under the same base station apparatus. Therefore, the communication system in which the LGW is arranged is limited to communication between terminals under the same base station device, and communication other than between terminals under the same base station device is performed by PGW. It becomes difficult to use and aggregate. Therefore, when LGW is used, it becomes difficult to communicate with an external network, and it is used like extension communication under the same base station device. That is, in LGW, both terminal-to-terminal communication under the same base station device and communication with a device of an external network cannot be compatible.

Hereinafter, a communication system and a communication control method capable of improving communication efficiency between terminals generated by the same bearer while suppressing obstruction of communication between terminals generated by the same bearer will be provided.

FIG. 1 is a diagram showing a configuration example of the communication system 5 according to the embodiment. The communication system 5 includes a UE 10 (10A, 10B, ...), An eNB 30, and an EPC device 50. The EPC device 50 includes a PGW 51, an SGW 53, an MME (Mobility Management Entity) 54, and an HSS (Home Subscriber Server) 55. Each device in the communication system 5 is connected by an LTE network N1 (an example of a 3GPP network).

The UE 10 is an LTE terminal (an example of a 3GPP terminal), and exists in another communication device (for example, eNB 30, another UE 10 under the same eNB 30, another UE 10 under another eNB 30, and an external network N2 via the LTE network N1). It may be a terminal that communicates with a communication device). The UE 10 is owned by the user. There are a plurality of UE10s. The UE 10 has the same configuration as a general LTE terminal, and may have a processing unit, a communication unit, a display unit, an operation unit, a storage unit, and the like. A bearer is established between the UE 10 and the PGW 51 via the eNB 30.

The eNB 30 is connected to one or more UEs 10 under its control so as to be communicable. There may be one or a plurality of eNBs 30. The eNB 30 has the same configuration and function as a general eNB, and may have a processing unit, a communication unit, a display unit, an operation unit, a storage unit, and the like. The storage unit of the eNB 30 holds a table T1 described later. The storage unit of the eNB 30 may hold the table T2 described later. A plurality of eNBs 30 may exist in the communication system 5.

The processing unit of the eNB 30 realizes various functions by executing a program held in a memory by a processor (for example, a CPU). The storage unit of the eNB 30 may have, for example, a ROM, a RAM, or various storages (for example, HDD, SSD), and holds various information, data, and programs. The communication unit of the eNB 30 communicates (wired communication or wireless communication) with the UE 10 and the EPC device 50. Communication by eNB30 includes LTE communication. LTE communication may include VoLTE communication.

The EPC device 50 is a device located in the LTE core network and communicates with the eNB 30B according to the LTE protocol. Each node of PGW51, SGW53, MME54, and HSS55 of the EPC device 50 may be a logical node or a physical node. That is, the functions may be integrated into one device (server), or the functions may be distributed to a plurality of individual devices (servers). The EPC device 50 may also include a PCRF (not shown) node. The EPC device 50 is not limited to this configuration, and may include other ancillary elements. A plurality of EPC devices 50 may exist in the communication system 5.

MME54 and HSS55 process C-plane data, which is control data, together with PCRF. The SGW 53 and PGW 51 process U plane data which is user data. Therefore, for example, when U-plane data, that is, U-plane traffic from the external network N2 (upstream from the EPC device 50) to the UE 10A reaches the EPC device 50 from the external network N2, it reaches the EPC device 50 via the PGW 51, SGW 53, and eNB 30. , Is transmitted to the UE 10.

The MME 54 is a node connected to the eNB 30 and providing movement control and the like, and performs movement control such as location registration, paging, and handover, and establishment or deletion of a bearer (data communication path). A bearer is established between PGW 51 and UE 10 (see FIG. 1). Further, the connection relationship between each EPC device 50, each eNB 30, and each UE 10 is arbitrary, and bearers may be established in various combinations.

The HSS55 is a node having a subscriber management database in, for example, LTE (an example of 3GPP communication), and manages subscriber contract information, terminal information, authentication information, location information, and the like. This subscriber may include a user of UE10.

The SGW 53 is a gateway connected to the eNB 30, accommodates 3GPP access, and transmits data (user data) to the UE 10 and PGW 51.

The PGW 51 is a gateway that assigns an IP address to the UE 10, transfers packets, and the like at a connection point with the external network N2 (PDN). The PGW 51 may operate according to the policy (policy control information) possessed by the PCRF by cooperating with the PCRF. The PGW 51 may control communication via each bearer according to the policy of PCRF.

The EPC device 50 has a processing unit, a storage unit, and a communication unit. When each node of the EPC device 50 is a logical node, one device may be provided with a processing unit, a storage unit, and a communication unit. When each node of the EPC device 50 is a physical node, each node may be provided with a processing unit, a storage unit, and a communication unit.

The processing unit of the EPC device 50 realizes various functions by executing a program held in a memory by a processor (for example, a CPU). The storage unit of the EPC device 50 may have, for example, a ROM, RAM, or various storages (for example, HDD, SSD), and holds various information, data, and programs. The communication unit of the EPC device 50 communicates (wired communication or wireless communication) with various devices in the eNB 30 and the external network N2. Communication by the EPC device 50 includes LTE communication. LTE communication may include VoLTE communication.

FIG. 2 is a diagram showing an example of the table T1 held by the eNB 30. Table T1 holds attribute information about the bearer established between PGW 51 and UE 10. This attribute information includes, for example, a bearer ID, an APN (Access Point Name), and an IP address. The bearer information registered in the table T1 may differ depending on each eNB 30.

The bearer ID is an example of bearer identification information, and may be E-RAB_ID (ID for a wireless section), TE_ID (ID on the EPC device 50 side), or the like. The bearer ID may also be held in the UE 10 and PGW 51 which are the terminations of the bearer. Bearer IDs may be numbered in the order of registration in table T1.

The APN can be used as identification information for identifying the external network N2 to which the bearer is connected. For example, each bearer connected to the same external network N2 has the same APN. A plurality of PGW 51s may exist in the communication system 5. The APN is information that does not exist in the IP packet, and may be registered in advance in association with the bearer.

The IP address may be the IP address of the destination (for example, UE10) to which the eNB 30 transmits the IP packet. This IP address may be registered by the UE 10 or the EPC device 50 after the bearer is established, or may be determined and registered during the negotiation for establishing the bearer between the UE 10 and the EPC device 50.

For example, when a bearer is established by the PGW 51 via the eNB 30, the eNB 30 registers the attribute information regarding the established bearer in the table T1. When the connection to the communication system 5 is cut off or the UE 10 which is the terminal of the registered bearer is moved to another eNB 30 by handover or the like, the eNB 30 is the bearer whose UE 10 is the terminal from the table T1. Delete the information in. The eNB 30 does not have a function of terminating the bearer like LGW. Therefore, the eNB 30 has both a return function for communicating between the subordinate UEs 10 and a communication function between the UE 10 and the PGW 51.

FIG. 3 is a sequence diagram showing an operation example of the communication system 5.

First, the PGW 51 of the EPC device 50 establishes a bearer that connects each UE 10 included in the communication system 5 and the PGW 51 (S11). In the communication system 5, a plurality of EPC devices 50 may exist, a plurality of eNBs 30 may exist under the plurality of EPC devices 50, and a plurality of UEs 10 may exist under the plurality of eNBs 30. Therefore, there are a plurality of bearers. In establishing the bearer, authentication processing such as terminal authentication and user authentication may be performed.

The processing unit of the eNB 30 stores the APN, IP address information, etc. of each established bearer in the table T1, and causes the storage unit to hold the table T1 (S12). In this case, the APN and IP address of each bearer may be notified from the UE 10 side to the eNB 30 or from the EPC device 50 side (PGW 51 side) to the eNB 30. It should be noted that the table T1 may be held in advance of the table T1 in S12, not after S11 but before S11.

The communication unit of the UE 10A sends an IP packet (S13). For example, it is assumed that the UE 10A makes a call with another terminal. The IP packet includes information such as the IP address of the source and the IP address of the destination (destination).

The communication unit of the eNB 30 receives the IP packet from the UE 10A. The processing unit of the eNB 30 refers to the table T1 and determines whether or not there is a bearer having the same APN as the APN of the bearer to which the IP packet is transmitted (S14). When the bearer of the same APN does not exist, the processing unit of the eNB 30 determines that the IP packet is to the UE 10 or the external network N2 under the other eNB 30, and sends the IP packet to the EPC device 50 via the communication unit. (S15).

When a bearer of the same APN exists in S14, the processing unit of the eNB 30 refers to the table T1 and determines whether or not there is an IP address that is the bearer of this APN and matches the IP address of the destination of the IP packet. Judgment (S16). If there is no matching IP address, the processing unit of the eNB 30 determines that it is an IP packet to the UE 10 or the external network N2 under another eNB 30, and sends an IP packet to the EPC device 50 via the communication unit ( S17).

If there is a matching IP address in S16, the processing unit of the eNB 30 determines that it is an IP packet to the UE 10 (here, UE 10B) under the same eNB 30, and transmits the IP packet from the UE 10A via the communication unit. It returns and transmits (return communication) to the UE 10B (S18). Note that the return communication refers to, for example, communication between UEs 10 under the same eNB 30 and completed on the lower side of the eNB 30 including the eNB 30 without going through the EPC device 50 higher than the eNB 30.

In this way, when the communication system 5 establishes a bearer between the UE 10 and the PGW 51, the eNB 30 may collect, register, and retain the APN and IP address information of each bearer. When the UE 10 sends an IP packet using each bearer, the eNB 30 may determine whether or not a bearer with the same APN as the APN of the used bearer exists. When there are bearers with the same APN, it may be determined whether or not there are bearers with the same IP address as the destination of the IP packet. If there is a bearer with a matching IP address, the eNB 30 may forward the IP packet to the bearer.

According to the operation of the communication system 5 as described above, the return communication in the eNB 30 can be performed while using the bearer connected to the external network N2. Therefore, even when the communication between the UEs 10 under the eNB 30 (return communication) and the communication between the UE 10 under the eNB 30 and the external network N2 are mixed and used, the eNB 30 improves the communication efficiency by the return communication at the eNB 30. it can. In this way, a part of the functions of the SGW and the PGW conventionally on the EPC device side can be distributed and arranged on the eNB side.

From S13 onward in FIG. 3, the processes S14 to S18 are performed for each transmission of the IP packet. In S14 and S16, the table T1 is referred to and processed. Further, when a large number (for example, 100 units) of UEs 10 are connected under the eNB 30, the number of processes after S13 in FIG. 3 becomes large, and the number of references to the table T1 also becomes large. On the other hand, the table T1 may be divided into a plurality of tables. For example, the table T1 may be divided into a plurality of tables using, for example, an APN as a key. As a result, the processing using the table T1 can be speeded up.

(Modification example)
The PGW 51 may monitor the communication in the communication system 5 and acquire a trail (communication log) of all the communication in the communication system 5. In this case, if the eNB 30 lower than the PGW 51 performs back communication, it becomes difficult to monitor all the communications in the PGW 51. The communication log is, for example, a log that records and stores communication contents so that it can be confirmed that the usage and quality of the specifications of the communication system are appropriate.

On the other hand, the eNB 30 may hold the table T2 together with the table T1 in the storage unit. FIG. 4 is a diagram showing an example of the table T2 held by the eNB 30. The table T2 holds information on whether or not to allow the return for each APN. As a specific example, the table T2 holds APN information and information on whether or not to allow return communication.

Even if the eNB 30 determines that the acquired IP packet is the target of the return communication at the stage of referring to the table T1, the APN corresponding to the bearer to which the acquired IP packet is transmitted returns the return communication at the stage of referring to the table T2. If is not permitted, return communication will not be performed. Then, the eNB 30 forwards this IP packet to the EPC device 50. On the other hand, in the eNB 30, when the acquired IP packet is determined to be the target of the return communication at the stage of referring to the table T1, the APN corresponding to the bearer to which the acquired IP packet is transmitted is determined at the stage of referring to the table T2. If return communication is permitted, return communication is performed.

The eNB 30 may dynamically rewrite the information on whether or not to allow the return at the APN in the table T2. For example, the eNB 30 may rewrite the information on whether or not to allow the return in the APN in the table T2 at the timing when the PGW 51 acquires the log. When the log of PGW 51 is acquired periodically, the eNB 30 retains the information of the log acquisition timing, and when the log acquisition timing comes, for example, the information on whether or not to allow the return at the APN in the table T2. May be changed to information that does not allow wrapping. If it is performed irregularly, the eNB 30 receives information indicating the log acquisition timing from the PGW 51 (or MME 54), and depending on the reception of the log acquisition timing, for example, whether or not to allow the return at the APN in the table T2 is permitted. The information may be changed to information that does not allow wrapping.

In this way, by holding the table T2 in the eNB 30, the communication system 5 can be connected to the state of the UE 10 or the PGW 51 (for example, a predetermined operation by the PGW 51) even when the connection is permitted by the attribute information of the bearer. At that time, depending on the position of the UE 10), it is possible not to allow the return communication.

As described above, the communication system 5 of the present embodiment communicates according to the LTE communication method and may include a base station device (for example, eNB 30) and a core network device (for example, EPC device 50). The base station apparatus may hold attribute information for establishing a bearer between the core network apparatus and each terminal (for example, UE 10) connected to the base station apparatus. The attribute information may include first information (for example, APN) for identifying the external network N2 on the core network device side in the bearer, and second information indicating the IP address of the terminal in the bearer. The core network device may establish a bearer with a terminal connected to the base station device. The base station apparatus may receive an IP packet from the first terminal (for example, UE10A). The base station device may determine whether or not the information identifying the external network N2 on the core network device side of the bearer to which the IP packet is transmitted matches the first information held by the base station device. .. The base station apparatus may determine whether or not the IP address included in the IP packet and the second information held by the base station apparatus match. When the first information matches and the second information matches, the base station apparatus uses the bearer specified by the first information and the second information, and uses the bearer specified by the first information to the bearer terminal from the first terminal. Return communication may be performed by transmitting an IP packet to a second terminal (for example, UE10B) which is a terminal terminal device on the side.

As a result, the base station apparatus determines whether or not to perform the return communication based on the first information and the second information. Therefore, the timing of the return communication is limited, and the return communication and the non-return communication are performed. Can be compatible with. Therefore, it is possible to eliminate exclusive control such as LGW that only performs return communication, and it is possible to carry out communication between the same bearers and communication between different bearers. Further, the return communication in the eNB 30 can be performed while using the bearer terminated by the external network N2 on the core network device side. Therefore, the communication system 5 can improve the communication efficiency between the terminals generated by the same bearer while suppressing the obstruction of the communication between the terminals generated by the same bearer.

If the first information does not match or the second information does not match, the base station apparatus may transmit an IP packet from the first terminal to the core network apparatus.

As a result, the base station device can send the IP packet from the first terminal to the core network device without returning. Therefore, the base station apparatus can carry out return communication, and can communicate with, for example, a terminal under another base station apparatus or a device on an external network.

Further, the first information may include information on the access point name. As a result, the base station apparatus can determine the return communication by using the APN for identifying the PGW 51.

In addition, the base station apparatus may hold a third piece of information indicating whether or not the return communication is permitted for each of the above-mentioned first pieces of information. The base station apparatus may perform return communication when the above-mentioned first information matches, the above-mentioned second information matches, and the third information indicates permission for return communication. The base station apparatus does not have to perform the return communication when the third information indicates that the return communication is not permitted.

As a result, the base station apparatus can suppress that the acquired IP packet is uniformly allowed to return communication even when the bearer attribute information such as the first information and the second information match. .. For example, even if the return communication is not permitted depending on the timing, or the return communication is not permitted depending on the location, the base station apparatus can accurately determine whether or not the return communication is performed.

Further, the above-mentioned third information can change the permission and non-permission of the return communication. For example, the base station device allows the return communication in consideration of the state of the terminal and the core network device related to the bearer. Or you can decide whether to permit or not, and you can change the permit or disapproval as the situation changes.

Further, the base station apparatus may set information for disallowing the return communication as the third information at the timing when the core network apparatus acquires the communication log.

Thereby, for example, when the base station apparatus monitors the communication in the communication system 5 by the core network apparatus and acquires the log of all the communications in the communication system 5, the base station apparatus on the lower side than the core network apparatus. It is possible to suppress the return communication by the PGW 51, and it is possible to easily monitor all the communications in the PGW 51.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present disclosure is not limited to such examples. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the claims, which naturally belong to the technical scope of the present disclosure. Understood.

The present disclosure is useful for communication systems, communication control methods, and the like that can improve communication efficiency between terminals generated by the same bearer while suppressing obstruction of communication between terminals generated by the same bearer.

5 Communication system 10A, 10B UE
30 eNB
50 EPC device 51 PGW
53 SGW
54 MME
55 HSS
N1 LTE network N2 external network

Claims (7)

A communication system that communicates according to the LTE communication method and includes a base station device and a core network device.
The base station apparatus holds attribute information for establishing a bearer between the core network apparatus and each terminal connected to the base station apparatus.
The attribute information includes first information for identifying an external network on the core network device side in the bearer and second information indicating the IP address of the terminal in the bearer.
The core network device establishes a bearer with a terminal connected to the base station device.
The base station device is
Receive an IP packet from the first terminal
It is determined whether or not the information identifying the external network on the core network device side of the bearer to which the IP packet is transmitted and the first information held by the base station device match.
It is determined whether or not the IP address included in the IP packet and the second information held by the base station apparatus match.
When the first information matches and the second information matches, the bearer specified by the first information and the second information is used to obtain the bearer from the first terminal. The IP packet is transmitted to the second terminal, which is the terminal device on the terminal side, and the return communication is performed.
Communications system. If the first information does not match, or if the second information does not match, the base station apparatus transmits an IP packet from the first terminal to the core network apparatus.
The communication system according to claim 1. The first information includes information on the access point name.
The communication system according to claim 2. The base station device is
For each of the first information, a third information indicating whether or not the return communication is permitted is retained.
When the first information matches, the second information matches, and the third information indicates permission for the return communication, the return communication is performed.
If the third information does not indicate the disapproval of the return communication, the return communication is not performed.
The communication system according to any one of claims 1 to 3. The third information can change the permission and disapproval of the return communication.
The communication system according to claim 4. The base station device sets information for disallowing return communication as the third information at the timing when the core network device acquires the communication log.
The communication system according to claim 4 or 5. It is a communication control method in a communication system including a base station device and a core network device that communicates according to the LTE communication method.
The base station apparatus holds attribute information for establishing a bearer between the core network apparatus and each terminal connected to the base station apparatus.
The attribute information includes first information for identifying an external network on the core network device side in the bearer and second information indicating the IP address of the terminal in the bearer.
A step of establishing a bearer between the core network device and a terminal connected to the base station device,
The step of receiving an IP packet from the first terminal,
A step of determining whether or not the information identifying the external network on the core network device side of the bearer to which the IP packet is transmitted and the first information held by the base station device match.
A step of determining whether or not the IP address included in the IP packet and the second information held by the base station apparatus match.
When the first information matches and the second information matches, the bearer specified by the first information and the second information is used to obtain the bearer from the first terminal. A step of performing return communication, in which the IP packet is transmitted to a second terminal, which is a terminal device on the terminal side, and
Communication control method having.

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