CN108377582B

CN108377582B - Method, network element and system for deleting user plane tunnel

Info

Publication number: CN108377582B
Application number: CN201610963406.9A
Authority: CN
Inventors: 聂胜贤; 周润泽; 陈中平
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2016-11-04
Filing date: 2016-11-04
Publication date: 2021-02-23
Anticipated expiration: 2036-11-04
Also published as: CN113056038B; WO2018082517A1; CN108377582A; CN113056038A

Abstract

The embodiment of the invention provides a method, a network element and a system for deleting a user plane tunnel, and relates to the technical field of communication. The method is applied to a communication system, the communication system comprises a control plane network element and a user plane network element, and at least one user plane tunnel is arranged between the control plane network element and the user plane network element, and the method comprises the following steps: the control plane network element determines that a target user plane tunnel meeting preset conditions exists in at least one user plane tunnel; the control plane network element sends request information to the user plane network element, wherein the request information is used for indicating the user plane network element to delete a target user plane tunnel; and the user plane network element deletes the target user plane tunnel according to the request message. In the scheme of the embodiment of the invention, for the scene of separating the control plane and the user plane, the technical scheme of deleting the user plane tunnel between the control plane network element and the user plane network element is provided, so that the user plane tunnel can be deleted when not needed to be used, and the resource is saved.

Description

Method, network element and system for deleting user plane tunnel

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method, a network element, and a system for deleting a user plane tunnel.

Background

Control and User Plane Separation (CUPS) is a development trend of core network architecture. Different functional entities respectively execute the functions of a Control Plane (CP) and a User Plane (UP), so that the Control Plane and the User Plane can respectively use different software or hardware resources and can be deployed to different positions according to requirements, and higher flexibility is realized.

Taking a core Network of a fourth Generation (4th Generation, 4G) system as an example, the 3rd Generation Partnership Project (3 GPP) proposes to divide a Serving Gateway (SGW) and a Packet Data Gateway (PDN-GW or PGW) into a control plane functional entity and a user plane functional entity, respectively, and to add an interface between the control plane functional entity and the user plane functional entity. The SGW is divided into a control plane (serving gateway control plane) network element of the SGW and a user plane (serving gateway user plane) network element of the SGW, and the PGW is divided into a control plane (PDN gateway control plane) network element of the PGW and a user plane (PDN gateway user plane) network element of the PGW. The control plane network element and the user plane network element of the SGW may be respectively described as an SGW-C and an SGW-U, and the control plane network element and the user plane network element of the PGW may be respectively described as a PGW-C and a PGW-U. The SGW-C and the PGW-C may be deployed on the same physical device, and the combined SGW-C and PGW-C may be referred to as a combined gateway control plane network element, which may be described as SGW/PGW-C, for example; the SGW-U and the PGW-U may also be deployed on the same physical device, and the combined SGW-U and PGW-U may be referred to as a combined gateway user plane network element, which may be described as SGW/PGW-C, for example. The SGW-C, PGW-C, SGW/PGW-C belongs to a control plane network element, and the SGW-U, PGW-U, SGW/PGW-U belongs to a user plane network element. A control plane tunnel (control plane tunnel) and a user plane tunnel (user plane tunnel) are established between the control plane network element and the user plane network element, the control plane tunnel is mainly used for transmitting control plane signaling, and the user plane tunnel is mainly used for transmitting user plane data.

At present, in a scenario where a control plane and a user plane are separated, a user plane tunnel between a control plane network element and a user plane network element is also reserved all the time without data transmission, which causes resource waste.

Disclosure of Invention

The embodiment of the invention provides a method, a network element and a system for deleting a user plane tunnel, which are used for avoiding the problem of resource waste in the existing scheme.

In one aspect, an embodiment of the present invention provides a method for deleting a user plane tunnel, which is applied to a communication system, where the communication system includes a control plane network element and a user plane network element, and at least one user plane tunnel is provided between the control plane network element and the user plane network element. The method comprises the following steps: the control plane network element determines that a target user plane tunnel meeting preset conditions exists in at least one user plane tunnel; the control plane network element sends request information to the user plane network element, and the request information is used for indicating the user plane network element to delete a target user plane tunnel; and the user plane network element deletes the target user plane tunnel according to the request information.

In the scheme provided by the embodiment of the invention, the control plane network element determines that at least one user plane tunnel has a target user plane tunnel meeting the preset condition, and requests the user plane network element to delete the target user plane tunnel, so that for the scene of separation of the control plane and the user plane, the technical scheme for deleting the user plane tunnel between the control plane network element and the user plane network element is provided, the user plane tunnel is deleted when not needed, the long-term existence of the user plane tunnel is avoided, and the resource is saved.

Optionally, the preset conditions may be different for user plane tunnels with different granularities. The granularity corresponding to the user plane tunnel may be terminal granularity, session granularity, bearer granularity, or device granularity.

In one possible design, the user plane tunnel corresponds to a terminal granularity. Each of the at least one user plane tunnel is used for transmitting data related to a terminal. The target user plane tunnel is used for transmitting data related to the target terminal. The preset condition includes one of the following situations: (1) all sessions associated with the target terminal need to be deleted; (2) the cached data related to the target terminal in the control plane network element reaches the maximum caching amount allocated to the target terminal; (3) the data which is cached in the control plane network element and is related to the target terminal is completely sent to the user plane network element; (4) the control plane network element receives an indication of a lawful interception system indicating that it no longer needs to intercept data related to the target terminal.

In another possible design, the user plane tunnel corresponds to a session granularity. Each of the at least one user plane tunnel is used for transmitting data related to a session. The target user plane tunnel is used to transport data associated with the target session. The preset condition includes one of the following situations: (1) the target session needs to be deleted; (2) the target session comprises at least one session for transmitting data related to the target terminal, and the data related to the target terminal which is cached in the control plane network element reaches the maximum caching amount distributed for the target terminal; (3) the target session comprises at least one session for transmitting data related to the target terminal, and the data related to the target terminal cached in the control plane network element is completely sent to the user plane network element; (4) the target session comprises at least one session for transmitting data related to the target terminal, and the control plane network element receives an indication of the lawful interception system indicating that it is no longer necessary to intercept data related to the target terminal.

In another possible design, the user plane tunnel corresponds to a bearer granularity. Each of the at least one user plane tunnel is used for transmitting data related to a bearer. The target user plane tunnel is used for transmitting data related to the target bearer. The preset condition includes one of the following situations: (1) the target bearer is at least one bearer for transmitting data related to the target session, and the target session needs to be deleted; (2) the target bearer is at least one bearer used for transmitting data related to the target terminal, and the data related to the target terminal which is cached in the control plane network element reaches the maximum caching amount allocated to the target terminal; (3) the target bearer is at least one bearer used for transmitting data related to the target terminal, and the data related to the target terminal cached in the control plane network element is completely sent to the user plane network element; (4) the target bearer is at least one bearer for transmitting data related to the target terminal, and the control plane network element receives an indication of the lawful interception system indicating that it is no longer necessary to intercept data related to the target terminal.

In another possible design, the user plane tunnel corresponds to a device granularity. The at least one user plane tunnel includes one user plane tunnel, and the target user plane tunnel is the one user plane tunnel. The target user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element. The preset condition includes one of the following situations: (1) all sessions transmitted through the one user plane tunnel need to be deleted; (2) the cached data related to each terminal in all the terminals in the control plane network element all reach the maximum caching amount distributed for each terminal; (3) all the data which are cached in the control plane network element and are related to all the terminals in all the terminals are sent to the user plane network element; (4) the control plane network element receives an indication of a lawful interception system indicating that it is no longer necessary to intercept data related to any of all terminals.

The embodiment of the invention respectively provides corresponding preset conditions aiming at different granularities corresponding to the user plane tunnel and 4 different application scenes such as session deletion, data caching, data forwarding, legal monitoring and the like, thereby realizing the deletion of the user plane tunnel according to requirements under different application scenes. The deletion of the user plane tunnel can be determined not completely by the service state between the terminal and the network element of the data network, and whether the user plane tunnel is deleted can be determined according to the actual data transmission requirement, when it is determined that no data needs to be transmitted on a certain user plane tunnel, the user plane tunnel can be deleted, so that the resources occupied by the user plane tunnel are released, and the purpose of saving the resources is achieved.

In yet another possible design, for a data caching scenario, the maximum amount of caching may also correspond to a user plane tunnel allocation. Accordingly, the preset conditions may be: the data transmitted from the user plane network element to the control plane network element through the target user plane tunnel has reached the maximum amount of buffering allocated for the target user plane tunnel. In this case, the granularity corresponding to the user plane tunnel may be device granularity, terminal granularity, session granularity, or bearer granularity.

In a possible design, after the user plane network element deletes the target user plane tunnel, response information may be sent to the control plane network element, where the response information is used to indicate that the target user plane tunnel has been successfully deleted. Accordingly, the control plane network element receives the response information from the user plane network element. By the above manner, the control plane network element can determine whether the target user plane tunnel is successfully deleted.

In a possible design, before or after the control plane network element sends the request information to the user plane network element, it may further be determined that a new user plane tunnel needs to be created, and a creation request is sent to the user plane network element, where the creation request is used to instruct the user plane network element to create the new user plane tunnel. Accordingly, the user plane network element may create a new user plane tunnel according to the creation request. The embodiment of the invention also provides a technical scheme for creating the user plane tunnel between the control plane network element and the user plane network element, so that the user plane tunnel is created when in need.

On the other hand, an embodiment of the present invention provides a control plane network element, where the control plane network element has a function of implementing a control plane network element behavior in the above method example. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions.

In one possible design, the control plane network element includes a processor and a communication interface, and the processor is configured to support the control plane network element to perform the corresponding functions in the above method. The communication interface is used for supporting communication between a control plane network element and a user plane network element or other equipment. Further, the control plane network element may further comprise a memory, coupled to the processor, that stores program instructions and data necessary for the control plane network element.

In another aspect, an embodiment of the present invention provides a user plane network element, where the user plane network element has a function of implementing a user plane network element behavior in the above method example. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions.

In one possible design, the structure of the user plane network element includes a processor and a communication interface, and the processor is configured to support the user plane network element to perform corresponding functions in the above method. The communication interface is used for supporting communication between the user plane network element and the control plane network element or other equipment. Further, the user plane element may further comprise a memory for coupling with the processor, which stores program instructions and data necessary for the user plane element.

In another aspect, an embodiment of the present invention provides a communication system, where the communication system includes the control plane network element and the user plane network element in the foregoing aspects.

In another aspect, an embodiment of the present invention provides a computer storage medium for storing computer software instructions for the control plane network element, which includes a program designed to execute the above aspects.

In yet another aspect, an embodiment of the present invention provides a computer storage medium for storing computer software instructions for a user plane network element described above, which includes a program designed to execute the above aspects.

Compared with the prior art, in the scheme of the embodiment of the invention, the control plane network element determines that the target user plane tunnel meeting the preset condition exists in at least one user plane tunnel, and requests the user plane network element to delete the target user plane tunnel, so that for the scene of separation of the control plane and the user plane, the technical scheme of deleting the user plane tunnel between the control plane network element and the user plane network element is provided, the user plane tunnel is deleted when not needed to be used, the user plane tunnel is prevented from existing for a long time, and resources are saved.

Drawings

FIG. 1A is a schematic diagram of a possible application scenario provided by an embodiment of the present invention;

FIG. 1B is a schematic diagram of a possible network architecture provided by an embodiment of the invention;

fig. 2 is a communication schematic diagram of a method for deleting a user plane tunnel according to an embodiment of the present invention;

fig. 3 is a communication diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention;

fig. 4 is a communication diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention;

fig. 5 is a communication diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention;

fig. 6 is a communication diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention;

fig. 7A is a schematic block diagram of a control plane network element according to an embodiment of the present invention;

fig. 7B is a schematic structural diagram of a control plane network element according to an embodiment of the present invention;

fig. 8A is a schematic block diagram of a user plane network element according to an embodiment of the present invention;

fig. 8B is a schematic structural diagram of a user plane network element according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention.

The network architecture and the service scenario described in the embodiment of the present invention are for more clearly illustrating the technical solution of the embodiment of the present invention, and do not limit the technical solution provided in the embodiment of the present invention, and it can be known by those skilled in the art that the technical solution provided in the embodiment of the present invention is also applicable to similar technical problems along with the evolution of the network architecture and the appearance of a new service scenario.

Some possible application scenarios and network architectures to which the embodiment of the present invention is applicable will be described below with reference to fig. 1A and 1B.

FIG. 1A illustrates one application scenario in which embodiments of the present invention may be applied. As shown in fig. 1A, a terminal accesses an Internet Protocol (IP) Service network, such as a Multimedia subsystem (IMS) network, a Packet Switched Streaming Service (simple PSS) network, and the like, through a radio access network and a core network. The technical solution described in the present invention can be applied to a Long Term Evolution (LTE) system or other wireless communication systems using various radio Access technologies, such as systems using Access technologies such as Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), and the like. Furthermore, the method can also be applied to an evolution system subsequent to the LTE system, such as a next Generation network system, i.e., a fifth Generation (5G) system. For clarity, the LTE system is only exemplified here. In the LTE system, an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) serves as a Radio Access Network, and an Evolved Packet Core (EPC) serves as a Core Network. The terminal accesses the IMS network through the E-UTRAN and the EPC.

Based on the above application scenarios, fig. 1B shows a possible network architecture provided by the embodiment of the present invention. As shown in fig. 1B, the network architecture includes: a control plane network element 110 and a user plane network element 120.

The control plane network element 110 is a network device for implementing the control plane function. For example, the control plane functions include management of radio resources, establishment of a radio connection, Quality of Service (QoS) guarantee of traffic, and the like. The user plane network element 120 is a network device for implementing a user plane function. The user plane functions mainly include sending and receiving service data.

One control plane network element 110 may control one or more user plane network elements 120, and one user plane network element 120 may also be controlled by one or more control plane network elements 110. There is at least one user plane tunnel (user plane tunnel) between the control plane network element 110 and the user plane network element 120. The user plane tunnel is used for transmitting user plane data, i.e. service data. In addition, there is at least one control plane tunnel (control plane tunnel) between the control plane network element 110 and the user plane network element 120. The control plane tunnel is used for transmitting control plane signaling.

Optionally, the control plane network element 110 and the user plane network element 120 are devices in a core network of the communication system. As shown in fig. 1B, the network architecture further includes: access network equipment 130 and terminals 140.

The access network device 130 may be a Base Station (BS), which is a device deployed in a radio access network to provide wireless communication functions for terminals. The base stations may include various forms of macro base stations, micro base stations, relay stations, access points, and the like. In systems using different radio access technologies, names of devices having a base station function may be different, for example, in an LTE system, referred to as an evolved node B (eNB or eNodeB), in a 3G communication system, referred to as a node B (node B), and so on. For convenience of description, in the embodiment of the present invention, the above-mentioned apparatus for providing a wireless communication function for a terminal is collectively referred to as an access network device.

The terminal 140 may include various handheld devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to a wireless modem with wireless communication capabilities, as well as various forms of User Equipment (UE), Mobile Stations (MS), terminal Equipment (terminal device), and so forth. For convenience of description, the above-mentioned devices are collectively referred to as a terminal.

The access network device 130 and the terminal 140 may communicate with each other via some air interface technology, for example, via cellular technology. In addition, the access network device 130, the control plane network element 110 and the user plane network element 120 may also implement mutual communication through an air interface technology, and the terminal 140 and the control plane network element 110 may also implement mutual communication through an air interface technology. The user plane Network element 120 may also have access to a Data Network (Data Network), such as a Public Data Network (PDN).

In the embodiments of the present invention, the terms "network" and "system" are often used interchangeably, but those skilled in the art can understand the meaning. In the embodiment of the present invention, the control plane network element 110 and the user plane network element 120 may have a plurality of possible implementation forms. For example, in the LTE system, the control plane network element 110 may be: SGW-C, PGW-C, control plane network element of Traffic Detection Function (TDF) entity, SGW/PGW-C; the user plane network element 120 may be: user plane network elements of the SGW-U, PGW-U, TDF entities, SGW/PGW-U, wherein control plane network elements and user plane network elements of the TDF entities may be described as TDF-C and TDF-U, respectively. For another example, in the Next Generation network, the control plane network element 110 may be a control plane network element of the Next Generation Network (NG), and the user plane network element 120 may be a user plane network element of the Next Generation network, where the control plane network element and the user plane network element of the Next Generation network may be described as NG-CP and NG-UP, respectively. It should be noted that, when the scheme of the embodiment of the present invention is applied to a 5G system or other systems that may appear in the future, names of a control plane network element, a user plane network element, an access network device, a terminal, etc. may change, but this does not affect the implementation of the scheme of the embodiment of the present invention.

At present, in a scenario where a control plane and a user plane are separated, a user plane tunnel between a control plane network element and a user plane network element is also reserved all the time without data transmission, which causes resource waste. In view of this, embodiments of the present invention provide a method for deleting a user plane tunnel, and a control plane network element, a user plane network element, and a system based on this method, where the method is applied in a communication system, the communication system includes the control plane network element and the user plane network element, and at least one user plane tunnel is provided between the control plane network element and the user plane network element. The technical scheme provided by the embodiment of the invention has the core idea that the preset condition for triggering the deletion of the user plane tunnel is set, and when a certain user plane tunnel meets the preset condition, the user plane tunnel is deleted.

The embodiments of the present invention will be described in further detail below based on the common aspects related to the embodiments of the present invention described above.

Fig. 2 is a communication schematic diagram of a method for deleting a user plane tunnel according to an embodiment of the present invention. The method may include the following.

In part 201, the control plane network element determines that a target user plane tunnel meeting a preset condition exists in at least one user plane tunnel.

Specifically, at least one user plane tunnel is provided between the control plane network element and the user plane network element. The number of user plane tunnels between the control plane network element and the user plane network element may be different for different granularities corresponding to the user plane tunnels. For example, when the user plane tunnel corresponds to the device granularity, there is a user plane tunnel between the control plane network element and the user plane network element. For another example, when the user plane tunnel corresponds to the terminal granularity, there is at least one user plane tunnel between the control plane network element and the user plane network element, and each of the at least one user plane tunnel is used for transmitting data related to one terminal. For another example, when the user plane tunnel corresponds to the session granularity, there is at least one user plane tunnel between the control plane network element and the user plane network element, and each of the at least one user plane tunnel is used for transmitting data related to one session. For another example, when the user plane tunnel corresponds to a bearer granularity, at least one user plane tunnel is located between the control plane network element and the user plane network element, and each of the at least one user plane tunnel is used for transmitting data related to one bearer.

The session (session), bearer (bearer), preset conditions, target user plane tunnel, etc. referred to above are exemplarily described below.

A session may refer to a communicative interaction between two devices during a particular time of operation without interruption. During a session, all messages transmitted between two devices belong to the session. In the embodiment of the present invention, a session refers to a communication interaction between a terminal and a network element in a data network for transmitting service data. Data associated with a terminal may be transmitted over at least one session.

A bearer may refer to a data path used to transport wireless traffic data. The bearer referred to in the embodiments of the present invention may also be referred to as a radio bearer, and refers to a data path used for transmitting service data between a terminal and a network element in a data network. Data associated with one terminal may be transmitted through at least one session and data associated with one session may be transmitted through at least one bearer.

The preset condition may refer to a predetermined determination condition for determining whether the user plane tunnel needs to be deleted. In different application scenarios, the preset conditions are different. In addition, the preset conditions are different for the user plane tunnels with different granularities. For a detailed description of the preset conditions, see below.

The target user plane tunnel may be any one or more of the at least one user plane tunnel.

In part 202, the control plane network element sends request information to the user plane network element, where the request information is used to instruct the user plane network element to delete the target user plane tunnel.

Accordingly, the user plane network element receives the request information from the control plane network element.

In one example, the request information may carry at least one of: the indication information used for indicating deletion of the user plane tunnel, the identification of the target user plane tunnel, the message forwarding rule corresponding to the target user plane tunnel or the message matching rule corresponding to the target user plane tunnel.

In a possible implementation manner, the request information carries an identifier of the target user plane tunnel to notify the user plane network element of the target user plane tunnel that needs to be deleted. For example, when the granularity corresponding to the user plane tunnel is a terminal granularity, a session granularity, or a bearer granularity, since multiple user plane tunnels can be established between the control plane network element and the user plane network element, the request information needs to identify a target user plane tunnel to be deleted in the request information in addition to carrying the indication information. For another example, when the granularity corresponding to the user plane tunnel is the device granularity, because there is only one user plane tunnel between the control plane network element and the user plane network element, the request information only needs to carry the indication information, and it is not necessary to carry the identifier of the user plane tunnel in the request information.

In a possible implementation manner, the request information carries a packet forwarding rule and/or a packet matching rule corresponding to the target user plane tunnel, so that the user plane network element can delete the packet forwarding rule and/or the packet matching rule corresponding to the target user plane tunnel and other context information accordingly.

In part 203, the user plane network element deletes the target user plane tunnel according to the request message.

Specifically, after receiving the request message, the user plane network element may determine a target user plane tunnel to be deleted, and then delete the target user plane tunnel. For example, the deletion of the target user plane tunnel by the user plane network element may be implemented as follows: and releasing resources occupied by the target user plane tunnel, deleting context information corresponding to the target user plane tunnel, and the like.

In one example, after deleting the target user plane tunnel, the user plane network element may send response information to the control plane network element, where the response information is used to indicate that the target user plane tunnel has been successfully deleted. Accordingly, after receiving the response information from the user plane network element, the control plane network element may determine that the target user plane tunnel has been deleted.

It should be noted that, as described above, the control plane network element and the user plane network element may have at least one control plane tunnel in addition to at least one user plane tunnel. The request information and the response information can be received and transmitted between the control plane network element and the user plane network element through the control plane tunnel.

In the scheme provided by the embodiment of the invention, the control plane network element determines that the target user plane tunnel meeting the preset condition exists in at least one user plane tunnel, and requests the user plane network element to delete the target user plane tunnel, so that for the scene of separation of the control plane and the user plane, the technical scheme for deleting the user plane tunnel between the control plane network element and the user plane network element is provided, the user plane tunnel can be deleted when not in use, the long-term existence of the user plane tunnel is avoided, and the resource is saved.

Next, the preset conditions related to the embodiment of the present invention are further described with respect to different granularities corresponding to the user plane tunnel.

1. User plane tunnel corresponding terminal granularity

When the user plane tunnel corresponds to the terminal granularity, each of at least one user plane tunnel between the control plane network element and the user plane network element is used for transmitting data related to one terminal. The target user plane tunnel is used for transmitting data related to a target terminal, and the target terminal is any one of all terminals commonly served by the control plane network element and the user plane network element. The preset condition may include one of the following cases:

(a) all sessions associated with the target terminal need to be deleted.

In this case, the user plane tunnel may be deleted in the session deletion scenario.

The number of sessions associated with the target terminal may be one or more. These target terminal-related sessions are used for transmitting target terminal-related data. For example, the data related to the target terminal includes: the target terminal sends uplink service data to the network element in the data network, and the network element in the data network sends downlink service data to the target terminal. When the user plane tunnel corresponds to the terminal granularity, assuming that the target terminal corresponds to the target user plane tunnel, data of all sessions related to the target terminal is transmitted on the target user plane tunnel. When all the sessions related to the target terminal need to be deleted, it is indicated that no data related to the target terminal needs to be transmitted through the target user plane tunnel, and deletion of the target user plane tunnel is triggered at this time.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Wherein, the user plane tunnel 1 is used for transmitting data related to the terminal 1, the user plane tunnel 2 is used for transmitting data related to the terminal 2, and the user plane tunnel 3 is used for transmitting data related to the terminal 3. Taking terminal 1 as an example, assuming that 2 sessions are established between terminal 1 and a network element in a data network, when all of the 2 sessions need to be deleted, a control plane network element determines to delete a user plane tunnel 1 corresponding to terminal 1, the control plane network element sends request information carrying an identifier of user plane tunnel 1 to the user plane network element, and the user plane network element deletes user plane tunnel 1 after receiving the request information.

In addition, the reason why all sessions related to the target terminal need to be deleted may include one of the following situations: service interruption between a target terminal and a network element in a data network; a target terminal detachment process; finding that the target terminal still has activated context in a control plane network element due to unreasonable detachment in the prior art in the attachment process of the target terminal; and rejecting the update position of the target terminal in the tracking area update or routing area update process, and the like.

(b) The buffered data related to the target terminal in the control plane network element has reached the maximum buffer amount allocated for the target terminal.

In this case, the user plane tunnel may be deleted in the data caching scenario.

Specifically, when the target terminal is in an idle state, after receiving data related to the target terminal (for example, downlink service data sent by a network element in the data network to the target terminal), the user plane network element forwards the data related to the target terminal to the control plane network element through the target user plane tunnel, and the control plane network element caches the data. Subsequently, when the target terminal is restored from the idle state to the connected state, the control plane network element sends the cached data related to the target terminal to the user plane network element, and the user plane network element sends the data to the target terminal.

The control plane network element is configured with a maximum buffer amount allocated to each terminal. The maximum buffer amount corresponding to each terminal may be allocated by the control plane network element, or may be allocated by another device and notified to the control plane network element. For example, when the control plane network element is the SGW-C, the maximum buffer amount corresponding to each terminal may be allocated and notified to the SGW-C by a Mobility Management Entity (MME). The maximum buffer amount allocated to the target terminal refers to the maximum amount of data related to the target terminal that can be buffered by the control plane network element. The maximum buffer amounts allocated to different terminals may be the same or different, and this is not limited in this embodiment of the present invention. Optionally, the maximum buffer amount is a suggested number of downlink buffers (downlink buffered reported count). Taking the target terminal as an example, when the data related to the target terminal that has been cached in the control plane network element has reached the maximum caching amount allocated to the target terminal, the control plane network element cannot continue to store the data related to the target terminal, at this time, the user plane network element may not need to forward the data related to the target terminal to the control plane network element through the target user plane tunnel for caching, and the target user plane tunnel may be deleted.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Wherein, the user plane tunnel 1 is used for transmitting data related to the terminal 1, the user plane tunnel 2 is used for transmitting data related to the terminal 2, and the user plane tunnel 3 is used for transmitting data related to the terminal 3. Taking terminal 1 as an example, assume that the maximum buffer amount allocated to terminal 1 is a. When the terminal 1 is in an idle state, after receiving the data related to the terminal 1, the user plane network element forwards the data related to the terminal 1 to the control plane network element through the user plane tunnel 1, and the control plane network element caches the data. When the data related to the terminal 1, which is cached in the control plane network element, reaches the maximum caching amount a, the control plane network element determines to delete the user plane tunnel 1 corresponding to the terminal 1, the control plane network element sends request information carrying the identifier of the user plane tunnel 1 to the user plane network element, and the user plane network element deletes the user plane tunnel 1 after receiving the request information.

Illustratively, for the case of deleting the user plane tunnel in the data caching scenario, the involved control plane network element is SGW-C and the user plane network element is SGW-U, or the involved control plane network element is SGW/PGW-C and the user plane network element is SGW/PGW-U, or the involved control plane network element is NG-CP and the user plane network element is NG-UP.

(c) And the data which is cached in the control plane network element and is related to the target terminal is completely sent to the user plane network element.

In this case, the user plane tunnel may be deleted in the data forwarding scenario.

As already described above, when the target terminal is in the idle state, the user plane network element forwards the data related to the target terminal to the control plane network element through the target user plane tunnel after receiving the data related to the target terminal, and the control plane network element buffers the data. Subsequently, when the target terminal is restored from the idle state to the connected state, the control plane network element sends the cached data related to the target terminal to the user plane network element, and the user plane network element sends the data to the target terminal.

Taking the target terminal as an example, when all the data related to the target terminal cached in the control plane network element has been sent to the user plane network element, no data related to the target terminal in the control plane network element needs to be transmitted through the target user plane tunnel, and at this time, the target user plane tunnel may be deleted.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Wherein, the user plane tunnel 1 is used for transmitting data related to the terminal 1, the user plane tunnel 2 is used for transmitting data related to the terminal 2, and the user plane tunnel 3 is used for transmitting data related to the terminal 3. Taking the terminal 1 as an example, when the terminal 1 is restored from the idle state to the connected state, the control plane network element sends the buffered data related to the terminal 1 to the user plane network element through the user plane tunnel 1, and the user plane network element sends the data to the terminal 1. When the data related to the terminal 1 cached in the control plane network element is completely sent to the user plane network element, the control plane network element determines to delete the user plane tunnel 1 corresponding to the terminal 1, the control plane network element sends request information carrying the identifier of the user plane tunnel 1 to the user plane network element, and the user plane network element deletes the user plane tunnel 1 after receiving the request information.

Illustratively, for the case of deleting the user plane tunnel in the data forwarding scenario, the involved control plane network element is SGW-C and the user plane network element is SGW-U, or the involved control plane network element is SGW/PGW-C and the user plane network element is SGW/PGW-U, or the involved control plane network element is NG-CP and the user plane network element is NG-UP.

(d) The control plane network element receives an indication of a lawful interception system indicating that it no longer needs to intercept data related to the target terminal.

In this case, the user plane tunnel may be deleted in a lawful interception scenario.

In a legal monitoring scenario, if the legal monitoring system needs to monitor data related to the target terminal, the user plane network element sends the data related to the target terminal to the control plane network element through the target user plane tunnel after receiving the data related to the target terminal, and the control plane network element forwards the data to the legal monitoring system. The data sent by the user plane network element to the control plane network element may be a data copy generated by the user plane network element, and may also include other data type information. The data forwarded by the control plane network element to the lawful interception system may be data or other information processed by the control plane network element.

If the lawful monitoring system does not need to monitor the data related to the target terminal any more, the lawful monitoring system can send a lawful monitoring deactivation message to the control plane network element, the lawful monitoring deactivation message is used for indicating that the lawful monitoring function related to the target terminal is deactivated, the subsequent user plane network element does not need to send the data related to the target terminal to the control plane network element and then forwards the data to the lawful monitoring system, and at the moment, the target user plane tunnel can be deleted.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Wherein, the user plane tunnel 1 is used for transmitting data related to the terminal 1, the user plane tunnel 2 is used for transmitting data related to the terminal 2, and the user plane tunnel 3 is used for transmitting data related to the terminal 3. Taking the terminal 1 as an example, after the lawful interception system activates the lawful interception function related to the terminal 1, the user plane network element sends data related to the terminal 1 to the control plane network element through the user plane tunnel 1, and the control plane network element forwards the data to the lawful interception system. The control plane network element determines to delete the user plane tunnel 1 corresponding to the terminal 1 after receiving a lawful interception deactivation message which is sent by a lawful interception system and used for indicating deactivation of a lawful interception function related to the terminal 1, the control plane network element sends request information carrying an identifier of the user plane tunnel 1 to the user plane network element, and the user plane network element deletes the user plane tunnel 1 after receiving the request information.

Exemplarily, for a case of deleting a user plane tunnel in a lawful interception scenario, the involved control plane network element is an SGW-C and the user plane network element is an SGW-U, or the involved control plane network element is a PGW-C and the user plane network element is a PGW-U, or the involved control plane network element is an SGW/PGW-C and the user plane network element is an SGW/PGW-U, or the involved control plane network element is an NG-CP and the user plane network element is an NG-UP.

It should be noted that, when a user plane tunnel corresponds to a terminal granularity, a terminal may correspond to a user plane tunnel, and in this case, a target user plane tunnel corresponding to a target terminal is a user plane tunnel; alternatively, one terminal may correspond to at least two user plane tunnels, in which case, the target user plane tunnel corresponding to the target terminal may include at least two user plane tunnels.

2. User plane tunnel corresponding session granularity

Each of the at least one user plane tunnel between the control plane network element and the user plane network element is configured to transmit data associated with a session when the user plane tunnel corresponds to a session granularity. The target user plane tunnel is used to transport data associated with the target session. The preset condition may include one of the following cases:

(a) the target session needs to be deleted.

When the user plane tunnel corresponds to the session granularity, assuming that the target session corresponds to the target user plane tunnel, data related to the target session is transmitted on the target user plane tunnel. When the target session needs to be deleted, it indicates that no data related to the target session needs to be transmitted through the target user plane tunnel, and at this time, deletion of the target user plane tunnel is triggered.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Wherein, the user plane tunnel 1 is used for transmitting data related to the session 1, the user plane tunnel 2 is used for transmitting data related to the session 2, and the user plane tunnel 3 is used for transmitting data related to the session 3. Taking session 1 as an example, when session 1 needs to be deleted, the control plane network element determines to delete user plane tunnel 1 corresponding to session 1, the control plane network element sends request information carrying the identifier of user plane tunnel 1 to the user plane network element, and the user plane network element deletes user plane tunnel 1 after receiving the request information.

In addition, the reason why the target session needs to be deleted may include one of the following situations: service interruption between a target terminal and a network element in a data network; a target terminal detachment process; finding that the target terminal still has activated context in a control plane network element due to unreasonable detachment in the prior art in the attachment process of the target terminal; the updating position of the target terminal is rejected in the updating process of the tracking area or the routing area, and the session deletion process initiated by the target terminal or the network, and the like. Wherein the target session is a session between the target terminal and a network element of the data network.

(b) The target session comprises at least one session for transmitting data related to the target terminal, and the data related to the target terminal which is cached in the control plane network element reaches the maximum caching amount allocated for the target terminal.

The control plane network element is configured with a maximum buffer amount allocated to each terminal. The maximum buffer amount corresponding to each terminal may be allocated by the control plane network element, or may be allocated by another device and notified to the control plane network element. For example, when the control plane network element is the SGW-C, the MME may allocate and notify the maximum buffer amount corresponding to each terminal to the SGW-C. The maximum buffer amount allocated to the target terminal refers to the maximum amount of data related to the target terminal that can be buffered by the control plane network element. The maximum buffer amounts allocated to different terminals may be the same or different, and this is not limited in this embodiment of the present invention. Optionally, the maximum buffer amount is a suggested number of downlink buffers (downlink buffered reported count). Taking the target terminal as an example, when the data related to the target terminal that has been cached in the control plane network element has reached the maximum caching amount allocated to the target terminal, the control plane network element cannot continue to store the data related to the target terminal, at this time, the user plane network element may not need to forward the data related to the target terminal to the control plane network element through the target user plane tunnel for caching, and the target user plane tunnel may be deleted.

In one example, it is assumed that there are 5 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5. Wherein, the user plane tunnel 1 is used for transmitting data related to the session 1, the user plane tunnel 2 is used for transmitting data related to the session 2, the user plane tunnel 3 is used for transmitting data related to the session 3, the user plane tunnel 4 is used for transmitting data related to the session 4, and the user plane tunnel 5 is used for transmitting data related to the session 5. It is assumed that session 1, session 2 and session 3 are used for transmitting data related to terminal 1 and session 4 and session 5 are used for transmitting data related to terminal 2. Taking terminal 1 as an example, assume that the maximum buffer amount allocated to terminal 1 is a. When the terminal 1 is in an idle state, after receiving the data related to the terminal 1, the user plane network element forwards the data related to the terminal 1 to the control plane network element through one or more of the user plane tunnels 1, 2, and 3, and the control plane network element caches the data. When the data related to the terminal 1, which is cached in the control plane network element, reaches the maximum caching amount a, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, the control plane network element sends request information carrying the identifiers of the user plane tunnels 1, 2 and 3 to the user plane network element, and the user plane network element deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

(c) The target session includes at least one session for transmitting data related to the target terminal, and the data related to the target terminal cached in the control plane network element has been all sent to the user plane network element.

In one example, it is assumed that there are 5 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5. Wherein, the user plane tunnel 1 is used for transmitting data related to the session 1, the user plane tunnel 2 is used for transmitting data related to the session 2, the user plane tunnel 3 is used for transmitting data related to the session 3, the user plane tunnel 4 is used for transmitting data related to the session 4, and the user plane tunnel 5 is used for transmitting data related to the session 5. It is assumed that session 1, session 2 and session 3 are used for transmitting data related to terminal 1 and session 4 and session 5 are used for transmitting data related to terminal 2. Taking terminal 1 as an example, when terminal 1 returns to the connected state from the idle state, the control plane network element sends the buffered data related to terminal 1 to the user plane network element through one or more of user plane tunnels 1, 2, and 3, and the user plane network element sends the data to terminal 1. When the data related to the terminal 1 cached in the control plane network element is completely sent to the user plane network element, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, the control plane network element sends request information carrying the identifiers of the user plane tunnels 1, 2 and 3 to the user plane network element, and the user plane network element deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

(d) The target session comprises at least one session for transmitting data related to the target terminal, and the control plane network element receives an indication of the lawful interception system indicating that it is no longer necessary to intercept data related to the target terminal.

In one example, it is assumed that there are 5 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5. Wherein, the user plane tunnel 1 is used for transmitting data related to the session 1, the user plane tunnel 2 is used for transmitting data related to the session 2, the user plane tunnel 3 is used for transmitting data related to the session 3, the user plane tunnel 4 is used for transmitting data related to the session 4, and the user plane tunnel 5 is used for transmitting data related to the session 5. It is assumed that session 1, session 2 and session 3 are used for transmitting data related to terminal 1 and session 4 and session 5 are used for transmitting data related to terminal 2. Taking the terminal 1 as an example, after the lawful interception system activates the lawful interception function related to the terminal 1, the user plane network element sends data related to the terminal 1 to the control plane network element through one or more of the user plane tunnels 1, 2, and 3, and the control plane network element forwards the data to the lawful interception system. The control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1 after receiving a lawful interception deactivation message which is sent by a lawful interception system and used for indicating deactivation of a lawful interception function related to the terminal 1, the control plane network element sends request information carrying identifications of the user plane tunnels 1, 2 and 3 to the user plane network element, and the user plane network element deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

3. Corresponding bearer granularity of user plane tunnel

When the user plane tunnels correspond to bearer granularities, each of at least one user plane tunnel between the control plane network element and the user plane network element is used for transmitting data related to one bearer. The target user plane tunnel is used for transmitting data related to the target bearer. The preset condition includes one of the following situations:

(a) the target bearer is at least one bearer for transmitting data related to the target session, and the target session needs to be deleted.

When the target session needs to be deleted, it indicates that no data related to the target session needs to be transmitted through the target user plane tunnel, and at this time, deletion of the target user plane tunnel is triggered.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Wherein, the user plane tunnel 1 is used for transmitting data related to the bearer 1, the user plane tunnel 2 is used for transmitting data related to the bearer 2, and the user plane tunnel 3 is used for transmitting data related to the bearer 3. Assume that bearer 1 and bearer 2 are used to transport session 1 related data and bearer 3 is used to transport session 2 related data. Taking session 1 as an example, when session 1 needs to be deleted, the control plane network element determines to delete user plane tunnels 1 and 2 corresponding to session 1, the control plane network element sends request information carrying the identifiers of user plane tunnels 1 and 2 to the user plane network element, and the user plane network element deletes user plane tunnels 1 and 2 after receiving the request information.

In addition, the reason why the target session needs to be deleted may include one of the following situations: service interruption between a target terminal and a network element in a data network; a target terminal detachment process; finding that the target terminal still has activated context in the control plane network element due to unreasonable detachment in the attachment process; the updating position of the target terminal is rejected in the updating process of the tracking area or the routing area, and the session deletion process initiated by the target terminal or the network, and the like. Wherein the target session is a session between the target terminal and a network element of the data network.

(b) The target bearer is at least one bearer for transmitting data related to the target terminal, and the data related to the target terminal, which has been cached in the control plane network element, has reached the maximum caching amount allocated for the target terminal.

When the target terminal is in an idle state, after receiving data related to the target terminal (for example, downlink service data sent by a network element in a data network to the target terminal), the user plane network element forwards the data related to the target terminal to the control plane network element through the target user plane tunnel, and the control plane network element caches the data. Subsequently, when the target terminal is restored from the idle state to the connected state, the control plane network element sends the cached data related to the target terminal to the user plane network element, and the user plane network element sends the data to the target terminal.

In one example, it is assumed that there are 5 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5. The user plane tunnel 1 is used for transmitting data related to the bearer 1, the user plane tunnel 2 is used for transmitting data related to the bearer 2, the user plane tunnel 3 is used for transmitting data related to the bearer 3, the user plane tunnel 4 is used for transmitting data related to the bearer 4, and the user plane tunnel 5 is used for transmitting data related to the bearer 5. It is assumed that bearer 1, bearer 2 and bearer 3 are used for transmitting data related to terminal 1, and bearer 4 and bearer 5 are used for transmitting data related to terminal 2. Taking terminal 1 as an example, assume that the maximum buffer amount allocated to terminal 1 is a. When the terminal 1 is in an idle state, after receiving the data related to the terminal 1, the user plane network element forwards the data related to the terminal 1 to the control plane network element through one or more of the user plane tunnels 1, 2, and 3, and the control plane network element caches the data. When the data related to the terminal 1, which is cached in the control plane network element, reaches the maximum caching amount a, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, the control plane network element sends request information carrying the identifiers of the user plane tunnels 1, 2 and 3 to the user plane network element, and the user plane network element deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

(c) The target bearer is at least one bearer for transmitting data related to the target terminal, and the data related to the target terminal cached in the control plane network element has been completely sent to the user plane network element.

In one example, it is assumed that there are 5 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5. The user plane tunnel 1 is used for transmitting data related to the bearer 1, the user plane tunnel 2 is used for transmitting data related to the bearer 2, the user plane tunnel 3 is used for transmitting data related to the bearer 3, the user plane tunnel 4 is used for transmitting data related to the bearer 4, and the user plane tunnel 5 is used for transmitting data related to the bearer 5. It is assumed that bearer 1, bearer 2 and bearer 3 are used for transmitting data related to terminal 1, and bearer 4 and bearer 5 are used for transmitting data related to terminal 2. Taking terminal 1 as an example, when terminal 1 returns to the connected state from the idle state, the control plane network element sends the buffered data related to terminal 1 to the user plane network element through one or more of user plane tunnels 1, 2, and 3, and the user plane network element sends the data to terminal 1. When the data related to the terminal 1 cached in the control plane network element is completely sent to the user plane network element, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, the control plane network element sends request information carrying the identifiers of the user plane tunnels 1, 2 and 3 to the user plane network element, and the user plane network element deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

(d) The target bearer is at least one bearer for transmitting data related to the target terminal, and the control plane network element receives an indication of the lawful interception system indicating that it is no longer necessary to intercept data related to the target terminal.

In one example, it is assumed that there are 5 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5. The user plane tunnel 1 is used for transmitting data related to the bearer 1, the user plane tunnel 2 is used for transmitting data related to the bearer 2, the user plane tunnel 3 is used for transmitting data related to the bearer 3, the user plane tunnel 4 is used for transmitting data related to the bearer 4, and the user plane tunnel 5 is used for transmitting data related to the bearer 5. It is assumed that bearer 1, bearer 2 and bearer 3 are used for transmitting data related to terminal 1, and bearer 4 and bearer 5 are used for transmitting data related to terminal 2. Taking the terminal 1 as an example, after the lawful interception system activates the lawful interception function related to the terminal 1, the user plane network element sends data related to the terminal 1 to the control plane network element through one or more of the user plane tunnels 1, 2, and 3, and the control plane network element forwards the data to the lawful interception system. The control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1 after receiving a lawful interception deactivation message which is sent by a lawful interception system and used for indicating deactivation of a lawful interception function related to the terminal 1, the control plane network element sends request information carrying identifications of the user plane tunnels 1, 2 and 3 to the user plane network element, and the user plane network element deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

4. User plane tunnel corresponding device granularity

When the user plane tunnel corresponds to the device granularity, at least one user plane tunnel between the control plane network element and the user plane network element comprises one user plane tunnel, and the target user plane tunnel is the user plane tunnel. The target user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element. The preset condition may include one of the following cases:

(a) all sessions tunneled through the user plane need to be deleted.

Since there is only one user plane tunnel between the control plane network element and the user plane network element, all sessions between each terminal and the network element of the data network are transmitted on this user plane tunnel. If only part of the session needs to be deleted, this one user plane tunnel cannot be deleted for transmitting other non-deleted session related data. When all sessions need to be deleted, it indicates that no session needs to be transmitted on the user plane tunnel, and at this time, deletion of the user plane tunnel is triggered.

In one example, assuming that there is only one user plane tunnel between the control plane network element and the user plane network element, there are a total of 3 sessions between all terminals served by both the control plane network element and the user plane network element and the network elements of the data network, session 1, session 2 and session 3 respectively. The data associated with the 3 sessions are all tunnelled through the one user plane. When all the 3 sessions need to be deleted, the control plane network element determines to delete the user plane tunnel, the control plane network element sends request information to the user plane network element, and the user plane network element deletes the user plane tunnel after receiving the request information.

(b) The data buffered in the control plane network element and related to each terminal in all terminals has reached the maximum buffer amount allocated to each terminal.

For any terminal (taking a target terminal as an example) commonly served by the control plane network element and the user plane network element, when the target terminal is in an idle state, after receiving data related to the target terminal (for example, downlink service data sent by a network element in a data network to the target terminal), the user plane network element forwards the data related to the target terminal to the control plane network element through the user plane tunnel, and the control plane network element caches the data. Subsequently, when the target terminal is restored from the idle state to the connected state, the control plane network element sends the cached data related to the target terminal to the user plane network element through the user plane tunnel, and the user plane network element sends the data to the target terminal.

The control plane network element is configured with a maximum buffer amount allocated to each terminal. The maximum buffer amount corresponding to each terminal may be allocated by the control plane network element, or may be allocated by another device and notified to the control plane network element. For example, when the control plane network element is the SGW-C, the MME may allocate and notify the maximum buffer amount corresponding to each terminal to the SGW-C. The maximum buffer amount allocated to the target terminal refers to the maximum amount of data related to the target terminal that can be buffered by the control plane network element. The maximum buffer amounts allocated to different terminals may be the same or different, and this is not limited in this embodiment of the present invention. Optionally, the maximum buffer amount is a suggested number of downlink buffers (downlink buffered reported count). Taking the target terminal as an example, when the data related to the target terminal that has been cached in the control plane network element has reached the maximum caching amount allocated for the target terminal, the control plane network element cannot continue to store the data related to the target terminal. Since there is only one user plane tunnel between the control plane network element and the user plane network element, data related to each terminal is transmitted through the one user plane tunnel. If only some of the data buffered in the control plane network element by the terminal has reached the respective maximum buffer amount, this user plane tunnel cannot be deleted for transmitting data related to other terminals that have not reached the maximum buffer amount. And when the cached data of all the terminals in the control plane network element reach the respective corresponding maximum caching amount, triggering and deleting the user plane tunnel.

In one example, it is assumed that there is only one user plane tunnel between the control plane network element and the user plane network element, and all terminals commonly served by the control plane network element and the user plane network element include terminal 1, terminal 2, and terminal 3. Assuming that the maximum buffer amount allocated to each terminal is a, when the data related to each terminal cached in the control plane network element reaches the maximum buffer amount a, the control plane network element determines to delete the user plane tunnel, the control plane network element sends request information to the user plane network element, and the user plane network element deletes the user plane tunnel after receiving the request information.

(c) The data cached in the control plane network element and related to each of all the terminals has been completely sent to the user plane network element.

As already described above, when the target terminal is in the idle state, after receiving the data related to the target terminal, the user plane network element forwards the data related to the target terminal to the control plane network element through the above-mentioned one user plane tunnel, and the control plane network element buffers the data. Subsequently, when the target terminal is restored from the idle state to the connected state, the control plane network element sends the cached data related to the target terminal to the user plane network element through the user plane tunnel, and the user plane network element sends the data to the target terminal.

Since there is only one user plane tunnel between the control plane network element and the user plane network element, data related to each terminal is transmitted through the one user plane tunnel. If only part of the data buffered in the control plane network element by the terminal has been completely sent to the user plane network element, this user plane tunnel cannot be deleted for transmitting data related to the data buffered in the control plane network element that has not been completely sent to other terminals of the user plane network element. And when all the data cached by all the terminals in the control plane network element are sent to the user plane network element, triggering and deleting the user plane tunnel.

In one example, it is assumed that there is only one user plane tunnel between the control plane network element and the user plane network element, and all terminals commonly served by the control plane network element and the user plane network element include terminal 1, terminal 2, and terminal 3. When the data related to each terminal cached in the control plane network element is completely sent to the user plane network element, the control plane network element determines to delete the user plane tunnel, the control plane network element sends request information to the user plane network element, and the user plane network element deletes the user plane tunnel after receiving the request information.

(d) The control plane network element receives an indication of a lawful interception system, where the indication is used to indicate that data related to any of the terminals does not need to be intercepted any more.

In a lawful interception scenario, if the lawful interception system needs to intercept data related to any terminal (taking a target terminal as an example), after receiving the data related to the target terminal, the user plane network element sends the data related to the target terminal to the control plane network element through the target user plane tunnel, and the control plane network element forwards the data to the lawful interception system. The data sent by the user plane network element to the control plane network element may be a data copy generated by the user plane network element, and may also include other data type information. The data forwarded by the control plane network element to the lawful interception system may be data or other information processed by the control plane network element.

If the lawful interception system does not need to intercept data related to the target terminal any more, the lawful interception system can send a lawful interception deactivation message to the control plane network element, the lawful interception deactivation message is used for indicating that a lawful interception function related to the target terminal is deactivated, and the subsequent user plane network element does not need to send the data related to the target terminal to the control plane network element and then forwards the data to the lawful interception system. Since there is only one user plane tunnel between the control plane network element and the user plane network element, if the lawful interception system still needs to intercept data related to at least one terminal, this user plane tunnel cannot be deleted for transmitting data related to these terminals. When the lawful interception system no longer needs to intercept data related to any terminal, the deletion of the user plane tunnel is triggered.

In one example, it is assumed that there is only one user plane tunnel between the control plane network element and the user plane network element, and all terminals commonly served by the control plane network element and the user plane network element include terminal 1, terminal 2, and terminal 3. When the lawful monitoring system does not need to monitor data related to any terminal any more, the control plane network element determines to delete the user plane tunnel, the control plane network element sends request information to the user plane network element, and the user plane network element deletes the user plane tunnel after receiving the request information.

The preset conditions are introduced and explained above for different granularities corresponding to the user plane tunnel. Moreover, the preset conditions are introduced and explained from 4 different application scenarios, such as session deletion, data caching, data forwarding, lawful interception and the like. For the data caching scenario, the above only takes the allocation of the maximum caching amount to the terminal as an example. In other possible embodiments, the maximum amount of buffering may also correspond to the user plane tunnel allocation. That is, the control plane network element is configured with the maximum buffer amount allocated to each user plane tunnel. The maximum buffer amount corresponding to each user plane tunnel may be allocated by the control plane network element, or may be allocated by another device and notified to the control plane network element. For example, when the control plane network element is the SGW-C, the maximum buffer amount corresponding to each user plane tunnel may be allocated and notified to the SGW-C by the MME. The maximum buffer amount allocated to the target user plane tunnel refers to the maximum amount of data that the control plane network element can buffer and receive from the user plane network element through the target user plane tunnel. When there are multiple user plane tunnels, the maximum buffer amounts allocated to different user plane tunnels may be the same or different, and this is not limited in the embodiment of the present invention. In this case, the preset conditions are: the data transmitted from the user plane network element to the control plane network element through the target user plane tunnel has reached the maximum amount of buffering allocated for the target user plane tunnel. When the cached data transmitted through the target user plane tunnel in the control plane network element reaches the maximum caching amount allocated to the target user plane tunnel, the control plane network element cannot continue to store the data received through the target user plane tunnel, at this time, the user plane network element does not need to forward the data to the control plane network element for caching through the target user plane tunnel, and the target user plane tunnel can be deleted.

In one example, it is assumed that there are 3 user plane tunnels between the control plane network element and the user plane network element, respectively user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3. Assuming that the maximum buffer amount allocated to each user plane tunnel is a, taking the user plane tunnel 1 as an example, when data transmitted from the user plane network element to the control plane network element through the user plane tunnel 1 reaches the maximum buffer amount a, the control plane network element determines to delete the user plane tunnel 1, the control plane network element sends request information carrying an identifier of the user plane tunnel 1 to the user plane network element, and the user plane network element deletes the user plane tunnel 1 after receiving the request information.

In addition, under the condition that the maximum buffer amount corresponds to the allocation of the user plane tunnel, the granularity corresponding to the user plane tunnel may be a device granularity, a terminal granularity, a session granularity, or a bearer granularity, which is not limited in the embodiment of the present invention.

In an optional embodiment provided based on the embodiment shown in fig. 2, as shown in fig. 3, before or after the control plane network element sends the request information to the user plane network element, that is, before or after part 202, the method may further include the following steps:

at part 204, the control plane network element determines that a new user plane tunnel needs to be created.

Specifically, the control plane network element may determine that a new user plane tunnel needs to be created when it is detected that the creation condition is met. The creation conditions may be different for different granularities and different application scenarios corresponding to the user plane tunnel. The following describes the creation conditions.

1. User plane tunnel corresponding terminal granularity

Each user plane tunnel is used for transmitting data related to one terminal when the user plane tunnel corresponds to the terminal granularity. The new user plane tunnel created is requested for transmitting data related to the serving terminal. The service terminal is a terminal commonly served by the control plane network element and the user plane network element, and a user plane tunnel corresponding to the terminal is not created temporarily. The creation condition may include one of the following cases: (a) a session related to the service terminal needs to be created; (b) the service terminal is restored to a connection state from an idle state, the control plane network element needs to send the cached data related to the service terminal to the user plane network element, and the user plane network element sends the data to the service terminal; (c) the service terminal is converted from a connection state to an idle state, and the control plane network element needs to receive and cache data related to the service terminal from the user plane network element; (d) the control plane network element receives the indication of the lawful interception system that data related to the service terminal needs to be intercepted.

2. User plane tunnel corresponding session granularity

Each user plane tunnel is used to transport data associated with one session when the user plane tunnel corresponds to a session granularity. The new user plane tunnel requested to be created is used to transfer data related to a new session, which is a session that is not created temporarily. The creation condition may include one of the following cases: (a) a new session needs to be created; (b) the new session comprises at least one session for transmitting data related to the service terminal, the service terminal is restored from an idle state to a connected state, the control plane network element needs to send the cached data related to the service terminal to the user plane network element, and the user plane network element sends the data to the service terminal; (c) the new session comprises at least one session for transmitting data related to the service terminal, the service terminal is switched from a connected state to an idle state, and the control plane network element needs to receive and cache the data related to the service terminal from the user plane network element; (d) the new session comprises at least one session for transmitting data related to the serving terminal, and the control plane network element receives an indication of a lawful interception system that data related to the serving terminal needs to be intercepted.

For the above (b), (c), and (d) cases, the service terminal is a terminal commonly served by the control plane network element and the user plane network element.

3. Corresponding bearer granularity of user plane tunnel

When the user plane tunnels correspond to bearer granularities, each user plane tunnel is used for transmitting data related to one bearer. The new user plane tunnel requested to be created is used for transmitting data related to a new bearer, which is a bearer that is not created temporarily. The creation condition may include one of the following cases: (a) the new bearer comprises at least one bearer for transmitting data related to a new session, the new session needs to be created, and the new session refers to a session which is not created temporarily; (b) the new bearer comprises at least one bearer for transmitting data related to the service terminal, the service terminal is restored from an idle state to a connected state, the control plane network element needs to send the cached data related to the service terminal to the user plane network element, and the user plane network element sends the data to the service terminal; (c) the new bearer comprises at least one bearer for transmitting data related to the service terminal, the service terminal is switched from a connected state to an idle state, and the control plane network element needs to receive and cache the data related to the service terminal from the user plane network element; (d) the new bearer comprises at least one bearer for transmitting data related to the serving terminal, and the control plane network element receives an indication of a lawful interception system that interception of the data related to the serving terminal is required.

4. User plane tunnel corresponding device granularity

When the user plane tunnel corresponds to the device granularity, since only one user plane tunnel is provided between the control plane network element and the user plane network element, the new user plane tunnel requested to be created is the user plane tunnel. This one user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element. The creation condition may include one of the following cases: (a) a session transmitted through the user plane tunnel needs to be created, and the session may be a session that any one of the above terminals needs to create; (b) any one of the terminals is restored to the connected state from the idle state, the control plane network element needs to send the cached data related to the terminal to the user plane network element, and the user plane network element sends the data to the terminal; (c) any one of the terminals is switched from a connected state to an idle state, and the control plane network element needs to receive and cache data related to the terminal from the user plane network element; (d) and the control plane network element receives the indication of the legal monitoring system that the data related to any terminal in all the terminals needs to be monitored.

In part 205, the control plane network element sends a create request to the user plane network element, where the create request is used to instruct the user plane network element to create a new user plane tunnel.

Accordingly, the user plane network element receives a create request from the control plane network element.

In one example, the creation request may carry at least one of: the indication information is used for indicating the establishment of the user plane tunnel, the identification of the new user plane tunnel, the message forwarding rule corresponding to the new user plane tunnel or the message matching rule corresponding to the new user plane tunnel.

In a possible implementation manner, the creation request carries an identifier of the new user plane tunnel requested to be created, so as to notify the user plane element of the new user plane tunnel that needs to be created. For example, when the granularity corresponding to the user plane tunnel is a terminal granularity, a session granularity, or a bearer granularity, since a plurality of user plane tunnels can be established between the control plane network element and the user plane network element, the creation request needs to identify a new user plane tunnel that is requested to be created in the creation request in addition to carrying the indication information. For another example, when the granularity corresponding to the user plane tunnel is the device granularity, because there is only one user plane tunnel between the control plane network element and the user plane network element, the creation request only needs to carry the indication information, and it is not necessary to carry the identifier of the user plane tunnel in the creation request.

In a possible implementation manner, the request information carries the packet forwarding rule and/or the packet matching rule corresponding to the new user plane tunnel requested to be created, so that the user plane network element can configure the packet forwarding rule and/or the packet matching rule corresponding to the created new user plane tunnel and other context information accordingly.

In part 206, the user plane network element creates a new user plane tunnel according to the creation request.

Specifically, the user plane network element may determine a new user plane tunnel to be created after receiving the creation request, and then create the new user plane tunnel. For example, the user plane network element creating a new user plane tunnel may be implemented by: allocating resources for the new user plane tunnel, configuring corresponding context information for the new user plane tunnel, and the like.

In one example, the user plane network element may send a create response to the control plane network element after creating the new user plane tunnel, the create response indicating that the new user plane tunnel has been successfully created. Accordingly, after receiving the creation response from the user plane network element, the control plane network element may confirm that the new user plane tunnel has been created.

In addition, the control plane network element and the user plane network element can receive and transmit a creation request and a creation response through the control plane tunnel.

As can be seen from the foregoing, the embodiment of the present invention further provides a technical solution for creating a user plane tunnel between a control plane network element and a user plane network element, so that the user plane tunnel can be created when there is a need.

The solution of the embodiment of the present invention will be further explained below with reference to fig. 4 to 6 on the basis of the methods shown in fig. 2 and 3. Among the methods shown in fig. 4 to fig. 6, the same or similar contents to those of the method shown in fig. 2 or fig. 3 may refer to the detailed description in fig. 2 or fig. 3, and are not repeated in the following.

Fig. 4 is a communication diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention. In fig. 4, the granularity of the terminal corresponding to the user plane tunnel and the application scenario as the data cache scenario are described as an example. The method may include the following.

In part 401, when the target terminal is in an idle state, the user plane network element sends data related to the target terminal to the control plane network element through a target user plane tunnel corresponding to the target terminal.

At 402, a control plane network element caches data related to a target terminal.

At 403, the control plane network element determines whether the buffered data associated with the target terminal has reached a maximum buffer amount allocated for the target terminal.

In part 404, if the cached data related to the target terminal has reached the maximum caching amount allocated to the target terminal, the control plane network element sends request information to the user plane network element, where the request information is used to instruct the user plane network element to delete the target user plane tunnel, and the request information carries an identifier of the target user plane tunnel.

In part 405, the user plane network element deletes the target user plane tunnel according to the request information.

The user plane network element sends a response message to the control plane network element, at 406.

When the target terminal returns from the idle state to the connected state, the control plane network element determines that a new user plane tunnel needs to be created, and the new user plane tunnel is used for transmitting the cached data related to the target terminal to the user plane network element in 407.

In part 408, the control plane network element sends a create request to the user plane network element, where the create request is used to instruct the user plane network element to create a new user plane tunnel.

In part 409, the user plane network element creates a new user plane tunnel according to the creation request.

In part 410, the user plane network element sends a create response to the control plane network element.

The control plane network element may then send the buffered data associated with the target terminal to the user plane network element through the new user plane tunnel.

In part 411, the control plane network element sends a session termination request to the user plane network element, where the session termination request is used to instruct the user plane network element to delete a session related to the target terminal.

At element 412, the user plane element deletes the session associated with the target terminal and deletes the user plane tunnel associated with the target terminal.

The user plane network element sends a session termination response to the control plane network element, 413.

Fig. 5 is a communication schematic diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention. Fig. 5 illustrates an example in which the user plane tunnel corresponds to a terminal granularity, and an application scenario is taken as a data forwarding scenario. The method may include the following.

In part 501, when the target terminal is restored from the idle state to the connected state, the control plane network element sends the cached data related to the target terminal to the user plane network element through the target user plane tunnel corresponding to the target terminal.

At element 502, the control plane network element determines whether all of the buffered data associated with the target terminal has been sent to the user plane network element.

In part 503, if all the data cached by the control plane network element and related to the target terminal has been sent to the user plane network element, the control plane network element sends request information to the user plane network element, where the request information is used to instruct the user plane network element to delete the target user plane tunnel, and the request information carries an identifier of the target user plane tunnel.

In part 504, the user plane network element deletes the target user plane tunnel according to the request message.

In part 505, the user plane network element sends response information to the control plane network element.

When the target terminal transitions from the connected state to the idle state, the control plane network element determines that a new user plane tunnel needs to be created, the new user plane tunnel being used to receive data related to the target terminal from the user plane network element in order to cache the data related to the target terminal in the control plane network element, at 506.

In part 507, the control plane network element sends a creation request to the user plane network element, where the creation request is used to instruct the user plane network element to create a new user plane tunnel.

In part 508, the user plane network element creates a new user plane tunnel according to the creation request.

In part 509, the user plane network element sends a create response to the control plane network element.

And then, the user plane network element can send the data related to the target terminal to the control plane network element through the new user plane tunnel, and the control plane network element receives and caches the data related to the target terminal.

In part 510, the control plane network element sends a session termination request to the user plane network element, where the session termination request is used to instruct the user plane network element to delete a session associated with the target terminal.

At 511, the user plane element deletes the session associated with the target terminal and deletes the user plane tunnel associated with the target terminal.

The user plane network element sends a session termination response to the control plane network element, at 512.

Fig. 6 is a communication diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention. In fig. 6, the granularity of the terminal corresponding to the user plane tunnel and the application scenario as the lawful interception scenario are taken as an example for explanation. The method may include the following.

In part 601, when the lawful interception function corresponding to the target terminal is in an activated state, the user plane network element sends data related to the target terminal to the control plane network element through the target user plane tunnel corresponding to the target terminal.

At 602, the control plane network element forwards data associated with the target terminal to the lawful interception system.

In part 603, the control plane network element receives a lawful interception deactivation message from the lawful interception system, where the lawful interception deactivation message is used to instruct to deactivate a lawful interception function related to the target terminal.

In part 604, the control plane network element sends request information to the user plane network element, where the request information is used to instruct the user plane network element to delete the target user plane tunnel, and the request information carries an identifier of the target user plane tunnel.

In 605, the user plane network element deletes the target user plane tunnel according to the request message.

The user plane network element sends a response message to the control plane network element, at 606.

In part 607, the control plane network element receives a lawful interception activation message from the lawful interception system, where the lawful interception activation message is used to instruct to activate a lawful interception function related to the target terminal.

In part 608, the control plane network element sends a create request to the user plane network element, the create request instructing the user plane network element to create a new user plane tunnel, the new user plane tunnel being used to receive data related to the target terminal from the user plane network element.

In part 609, the user plane network element creates a new user plane tunnel according to the creation request.

In part 610, the user plane network element sends a create response to the control plane network element.

And then, the user plane network element can send data related to the target terminal to the control plane network element through the new user plane tunnel, and the control plane network element receives and forwards the data related to the target terminal to the lawful interception system.

At 611, the control plane network element sends a session termination request to the user plane network element, where the session termination request is used to instruct the user plane network element to delete the session associated with the target terminal.

At 612, the user plane element deletes the session associated with the target terminal and deletes the user plane tunnel associated with the target terminal.

The user plane network element sends a session termination response to the control plane network element, section 613.

The above-mentioned scheme provided by the embodiment of the present invention is introduced mainly from the perspective of interaction between a control plane network element and a user plane network element. It is to be understood that the control plane network element and the user plane network element include corresponding hardware structures and/or software modules for performing the above functions. The elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein may be embodied in hardware or in a combination of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present teachings.

The embodiment of the present invention may perform functional unit division on a control plane network element or a user plane network element according to the above method example, for example, each functional unit may be divided corresponding to each function, or two or more functions may be integrated into one processing unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit. It should be noted that the division of the unit in the embodiment of the present invention is schematic, and is only a logic function division, and there may be another division manner in actual implementation.

In case of using integrated units, fig. 7A shows a possible structural diagram of the control plane network element involved in the above embodiment. The control plane network element 700 includes: a processing unit 702 and a communication unit 703. The processing unit 702 is configured to control and manage actions of the control plane network element, for example, the processing unit 702 is configured to support the control plane network element to perform processes 201 and 202 in fig. 2, processes 204 and 205 in fig. 3, processes 402 to 404, 407, 408 and 411 in fig. 4, processes 501 to 503, 506, 507 and 510 in fig. 5, processes 602 to 604, 607, 608 and 611 in fig. 6, and/or other processes for the technology described herein. The communication unit 703 is configured to support communication between a control plane network element and a user plane network element or other network entities. The control plane network element 700 may further comprise a storage unit 701 for storing program codes and data of the control plane network element 700.

The Processing Unit 702 may be a Processor or a controller, such as a Central Processing Unit (CPU), a general-purpose Processor, a Digital Signal Processor (DSP), an Application-Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, a transistor logic device, a hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. The processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, DSPs, and microprocessors, among others. The communication unit 703 may be a communication interface, a transceiver circuit, etc., where the communication interface is generically referred to and may include one or more interfaces, such as an interface between a control plane network element and a user plane network element. The memory unit 701 may be a memory.

When the processing unit 702 is a processor, the communication unit 703 is a communication interface, and the storage unit 701 is a memory, the control plane network element according to the embodiment of the present invention may be the control plane network element shown in fig. 7B.

Referring to fig. 7B, the control plane network element 710 includes: a processor 712, a communication interface 713, and a memory 711. Optionally, the control plane network element 710 may further include a bus 714. Wherein the communication interface 713, the processor 712, and the memory 711 may be connected to each other by a bus 714; the bus 714 may be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The bus 714 may be divided into an address bus, a data bus, a control bus, and the like. For ease of illustration, only one thick line is shown in FIG. 7B, but this is not intended to represent only one bus or type of bus.

The control plane network element shown in FIG. 7A or FIG. 7B may be SGW-C, PGW-C, TDF-C, SGW/PGW-C or NG-CP.

In case of using integrated units, fig. 8A shows a possible schematic structure of the user plane network element involved in the above embodiments. The user plane network element 800 comprises: a processing unit 802 and a communication unit 803. Processing unit 802 is configured to control and manage actions of the user plane network element, for example, processing unit 802 is configured to support the user plane network element to perform process 203 in fig. 2, process 206 in fig. 3, processes 401, 405, 406, 409, 410, 412, and 413 in fig. 4, processes 504, 505, 508, 509, 511, and 512 in fig. 5, processes 601, 605, 606, 609, 610, 612, and 613 in fig. 6, and/or other processes for the techniques described herein. The communication unit 803 is configured to support communication between a user plane network element and a control plane network element or other network entities. The user plane network element 800 may further comprise a storage unit 801 for storing program codes and data of the user plane network element 800.

The processing unit 802 may be a processor or a controller, and may be, for example, a CPU, a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. The processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, DSPs, and microprocessors, among others. The communication unit 803 may be a communication interface, a transceiver, a transceiving circuit, etc., wherein the communication interface is a generic term and may include one or more interfaces, such as an interface between a user plane network element and a control plane network element. The storage unit 801 may be a memory.

When the processing unit 802 is a processor, the communication unit 803 is a communication interface, and the storage unit 801 is a memory, the user plane network element according to the embodiment of the present invention may be the user plane network element shown in fig. 8B.

Referring to fig. 8B, the user plane network element 810 includes: processor 812, communications interface 813, memory 811. Optionally, the user plane network element 810 may also include a bus 814. Wherein the communication interface 813, the processor 812 and the memory 811 may be connected to each other by a bus 814; bus 814 may be a PCI bus or EISA bus, etc. The bus 814 may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one thick line is shown in FIG. 8B, but this is not intended to represent only one bus or type of bus.

The user plane network element shown in the above-mentioned fig. 8A or fig. 8B may be SGW-U, PGW-U, TDF-U, SGW/PGW-U or NG-UP.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied in hardware or in software executed by a processor. The software instructions may be comprised of corresponding software modules that may be stored in Random Access Memory (RAM), flash Memory, Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), registers, a hard disk, a removable disk, a compact disc Read Only Memory (CD-ROM), or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may reside in a control plane network element or a user plane network element. Of course, the processor and the storage medium may reside as discrete components in a control plane network element or a user plane network element.

Those skilled in the art will recognize that, in one or more of the examples described above, the functions described in connection with the embodiments of the invention may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the embodiments of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only specific embodiments of the present invention, and are not intended to limit the scope of the embodiments of the present invention.

Claims

1. A method for deleting a user plane tunnel between a control plane network element and a user plane network element is applied to a communication system, the communication system comprises the control plane network element, the user plane network element, an access network device and a terminal, at least one user plane tunnel is arranged between the control plane network element and the user plane network element, and the method comprises the following steps:

the control plane network element determines that a target user plane tunnel meeting preset conditions exists in the at least one user plane tunnel;

the control plane network element sends request information to the user plane network element, wherein the request information is used for indicating the user plane network element to delete the target user plane tunnel;

wherein, when each of the at least one user plane tunnel is used to transmit data related to a terminal and the target user plane tunnel is used to transmit data related to a target terminal, the preset condition includes one of the following situations:

all sessions associated with the target terminal need to be deleted;

the cached data related to the target terminal in the control plane network element reaches the maximum caching amount allocated to the target terminal;

the data which is cached in the control plane network element and is related to the target terminal is completely sent to the user plane network element;

the control plane network element receives an indication of a legal monitoring system, wherein the indication is used for indicating that data related to the target terminal does not need to be monitored any more;

the data transmitted from the user plane network element to the control plane network element through the target user plane tunnel has reached the maximum buffer amount allocated to the target user plane tunnel.

2. The method according to claim 1, wherein when each of the at least one user plane tunnel is used for transmitting data related to one session and the target user plane tunnel is used for transmitting data related to a target session, the preset condition comprises one of the following situations:

the target session needs to be deleted;

the target session comprises at least one session for transmitting data related to a target terminal, and the data related to the target terminal which is cached in the control plane network element reaches the maximum caching amount allocated to the target terminal;

the target session comprises at least one session for transmitting data related to a target terminal, and the data related to the target terminal cached in the control plane network element is completely sent to the user plane network element;

the target session comprises at least one session for transmitting data related to a target terminal, and the control plane network element receives an indication of a lawful interception system, wherein the indication is used for indicating that the data related to the target terminal does not need to be intercepted any more;

3. The method according to claim 1, wherein when each of the at least one user plane tunnel is used for transmitting data related to a bearer and the target user plane tunnel is used for transmitting data related to a target bearer, the preset condition comprises one of the following situations:

the target bearer is at least one bearer for transmitting data related to a target session, and the target session needs to be deleted;

the target bearer is at least one bearer used for transmitting data related to a target terminal, and the data related to the target terminal, which has been cached in the control plane network element, has reached a maximum caching amount allocated to the target terminal;

the target bearer is at least one bearer for transmitting data related to a target terminal, and the data related to the target terminal cached in the control plane network element is completely sent to the user plane network element;

the target bearer is at least one bearer used for transmitting data related to a target terminal, and the control plane network element receives an indication of a lawful monitoring system, wherein the indication is used for indicating that the data related to the target terminal does not need to be monitored any more;

4. The method of claim 1, wherein when the at least one user plane tunnel comprises one user plane tunnel, the target user plane tunnel is the one user plane tunnel, and the target user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element, the preset condition comprises one of the following situations:

all sessions transmitted through the user plane tunnel need to be deleted;

the cached data related to each terminal in all the terminals in the control plane network element reaches the maximum caching amount allocated to each terminal;

the data which is cached in the control plane network element and is related to each terminal in all the terminals is completely sent to the user plane network element;

the control plane network element receives an indication of a legal monitoring system, wherein the indication is used for indicating that data related to any terminal in all the terminals does not need to be monitored any more;

5. The method according to any of claims 1 to 4, wherein before or after the control plane network element sends the request information to the user plane network element, the method further comprises:

the control plane network element determines that a new user plane tunnel needs to be created;

and the control plane network element sends a creation request to the user plane network element, wherein the creation request is used for indicating the user plane network element to create the new user plane tunnel.

6. A method for deleting a user plane tunnel between a control plane network element and a user plane network element is applied to a communication system, the communication system comprises the control plane network element, the user plane network element, an access network device and a terminal, at least one user plane tunnel is arranged between the control plane network element and the user plane network element, and the method comprises the following steps:

the user plane network element receives request information from the control plane network element, wherein the request information is used for instructing the user plane network element to delete a target user plane tunnel which meets a preset condition in the at least one user plane tunnel;

the user plane network element deletes the target user plane tunnel according to the request information;

all sessions associated with the target terminal need to be deleted;

7. The method according to claim 6, wherein when each of the at least one user plane tunnel is used for transmitting data related to one session and the target user plane tunnel is used for transmitting data related to a target session, the preset condition comprises one of the following situations:

the target session needs to be deleted;

8. The method according to claim 6, wherein when each of the at least one user plane tunnel is used for transmitting data related to a bearer and the target user plane tunnel is used for transmitting data related to a target bearer, the preset condition comprises one of the following situations:

9. The method according to claim 6, wherein when the at least one user plane tunnel comprises one user plane tunnel, the target user plane tunnel is the one user plane tunnel, and the target user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element, the preset condition comprises one of the following situations:

all sessions transmitted through the user plane tunnel need to be deleted;

10. The method according to any of claims 6 to 9, wherein before or after the user plane network element receives the request information from the control plane network element, the method further comprises:

the user plane network element receives a creation request from the control plane network element, wherein the creation request is used for indicating the user plane network element to create a new user plane tunnel;

and the user plane network element creates the new user plane tunnel according to the creation request.

11. A control plane network element, applied to a communication system, where the communication system includes the control plane network element, a user plane network element, an access network device, and a terminal, where at least one user plane tunnel is provided between the control plane network element and the user plane network element, and the control plane network element includes: a processing unit and a communication unit;

the processing unit is used for determining that a target user plane tunnel meeting preset conditions exists in the at least one user plane tunnel; and is configured to send, to the user plane network element, request information through the communication unit, where the request information is used to instruct the user plane network element to delete the target user plane tunnel;

all sessions associated with the target terminal need to be deleted;

12. The control plane network element of claim 11, wherein when each of the at least one user plane tunnel is used for transmitting data related to one session and the target user plane tunnel is used for transmitting data related to a target session, the preset condition comprises one of the following situations:

the target session needs to be deleted;

13. The control plane network element of claim 11, wherein when each of the at least one user plane tunnel is used for transmitting data related to a bearer and the target user plane tunnel is used for transmitting data related to a target bearer, the preset condition comprises one of the following situations:

14. The control plane network element of claim 11, wherein when the at least one user plane tunnel comprises one user plane tunnel, the target user plane tunnel is the one user plane tunnel, and the target user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element, the preset condition comprises one of the following situations:

all sessions transmitted through the user plane tunnel need to be deleted;

15. The control plane network element of any of claims 11 to 14, wherein the processing unit is further configured to determine that a new user plane tunnel needs to be created before or after sending the request information to the user plane network element through the communication unit; and the communication unit is configured to send a creation request to the user plane network element, where the creation request is used to instruct the user plane network element to create the new user plane tunnel.

16. A user plane network element is applied to a communication system, the communication system comprises a control plane network element, the user plane network element, an access network device and a terminal, at least one user plane tunnel is arranged between the control plane network element and the user plane network element, and the user plane network element comprises: a processing unit and a communication unit;

the processing unit is configured to receive request information from the control plane network element through the communication unit, where the request information is used to instruct the user plane network element to delete a target user plane tunnel that meets a preset condition in the at least one user plane tunnel; and deleting the target user plane tunnel according to the request information;

all sessions associated with the target terminal need to be deleted;

17. The user plane network element of claim 16, wherein when each of the at least one user plane tunnel is used for transmitting data related to one session and the target user plane tunnel is used for transmitting data related to a target session, the preset condition comprises one of the following situations:

the target session needs to be deleted;

18. The user plane network element of claim 16, wherein when each of the at least one user plane tunnel is used for transmitting data related to a bearer and the target user plane tunnel is used for transmitting data related to a target bearer, the preset condition comprises one of the following situations:

19. The user plane network element of claim 16, wherein when the at least one user plane tunnel comprises one user plane tunnel, the target user plane tunnel is the one user plane tunnel, and the target user plane tunnel is used for transmitting data related to all terminals commonly served by the control plane network element and the user plane network element, the preset condition comprises one of the following situations:

all sessions transmitted through the user plane tunnel need to be deleted;

20. The user plane network element according to any of claims 16 to 19, wherein the processing unit is further configured to receive a create request from the control plane network element through the communication unit before or after receiving request information from the control plane network element through the communication unit, the create request being used to instruct the user plane network element to create a new user plane tunnel; and the new user plane tunnel is created according to the creation request.

21. A communication system, the communication system comprising: a control plane network element as claimed in any of claims 11 to 15 and a user plane network element as claimed in any of claims 16 to 20.