CN113056038B

CN113056038B - Method, network element and system for deleting user plane tunnel

Info

Publication number: CN113056038B
Application number: CN202110221115.3A
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: 2023-05-16
Anticipated expiration: 2036-11-04
Also published as: CN108377582B; 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, 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 surface network element determines that a target user surface tunnel which accords with a preset condition exists in at least one user surface 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; 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 from 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, thereby saving resources.

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 plane and user plane separation (Control and User Plane Separation, cup) is a 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 be deployed to different positions according to requirements, and higher flexibility is realized.

Taking the core network of the fourth generation (4th Generation,4G) system as an example, the third generation partnership project (the 3rd Generation Partnership Project,3GPP) proposes to divide a Serving Gateway (SGW) and a packet data Gateway (Packet Data Network Gateway, PDN-GW or PGW) into a control plane function and a user plane function, respectively, and to increase an interface between the control plane function and the user plane function. Wherein 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. Wherein, the control plane network element and the user plane network element of the SGW may be respectively described as SGW-C and SGW-U, and the control plane network element and the user plane network element of the PGW may be respectively described as PGW-C and PGW-U. The SGW-C and the PGW-C can be deployed on the same physical equipment, and the combined SGW-C and PGW-C can be called as a unified gateway control plane network element, for example, can be described as SGW/PGW-C; the SGW-U and the PGW-U can also be deployed on the same physical device, and the combined SGW-U and PGW-U can be called a unified gateway user plane network element, for example, can be described as SGW/PGW-C. 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 scene of separating a control plane from a user plane, a user plane tunnel between a control plane network element and a user plane network element is reserved all the time under the condition of no data transmission, so that resource waste is caused.

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 surface network element determines that a target user surface tunnel which accords with a preset condition exists in at least one user surface 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; 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 the target user plane tunnel which accords with 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 the technical scheme for deleting the user plane tunnel between the control plane network element and the user plane network element is provided for the scene of separating the control plane from the user plane, and the user plane tunnel is deleted when not needed to be used, so that the user plane tunnel is prevented from being stored for a long time, and resources are saved.

Optionally, the preset conditions may be different for user plane tunnels of different granularity. 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 tunnels correspond to terminal granularity. Each of the at least one user plane tunnel is configured to transmit data associated with one terminal. The target user plane tunnel is used for transmitting data related to the target terminal. The preset condition includes one of the following cases: (1) all sessions associated with the target terminal need to be deleted; (2) The data which is cached in the control surface network element and related to the target terminal reaches the maximum cache quantity allocated for the target terminal; (3) The data which is cached in the control plane network element and 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 interception of data related to the target terminal is no longer required.

In another possible design, the user plane tunnels correspond to session granularity. Each of the at least one user plane tunnel is configured to transmit data associated with a session. The target user plane tunnel is used to transport data related to the target session. The preset condition includes one of the following cases: (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 cache amount allocated 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 sent to the user plane network element entirely; (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 a 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 tunnels correspond to a bearer granularity. Each of the at least one user plane tunnel is configured to transmit data associated with one bearer. The target user plane tunnel is used to transport data related to the target bearer. The preset condition includes one of the following cases: (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 for transmitting data related to the target terminal, and the data related to the target terminal cached in the control plane network element reaches the maximum cache amount allocated for the target terminal; (3) 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 is sent to the user plane network element entirely; (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 a 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 tunnels correspond to device granularity. The at least one user plane tunnel includes a 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 includes one of the following cases: (1) All sessions tunneled through this one user plane need to be deleted; (2) The data which are cached in the control surface network element and related to each terminal in all terminals reach the maximum cache quantity distributed for each terminal; (3) The data which are cached in the control plane network element and related to each terminal in all terminals are all 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 the terminals.

The embodiment of the invention provides corresponding preset conditions for 4 different application scenes such as session deletion, data caching, data forwarding, legal monitoring and the like according to different granularities corresponding to the user plane tunnels, and realizes the deletion of the user plane tunnels according to needs under different application scenes. The deletion of the user plane tunnel can not be completely determined by the service state between the terminal and the network element of the data network, and can also determine whether to delete the user plane tunnel according to the actual data transmission requirement, and 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 as to release the resources occupied by the user plane tunnel, thereby achieving the purpose of saving resources.

In yet another possible design, the maximum amount of buffering may also correspond to user plane tunnel allocation for a data buffering scenario. 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 buffer size allocated for the target user plane tunnel. In this case, the granularity corresponding to the user plane tunnel may be a device granularity, a terminal granularity, a session granularity, or a bearer granularity.

In one possible design, after the user plane network element deletes the target user plane tunnel, response information may also 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 method, the control plane network element can confirm whether the target user plane tunnel is successfully deleted.

In one possible design, before or after the control plane network element sends the request information to the user plane network element, it may also determine that a new user plane tunnel needs to be created, and 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. 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 the need exists.

On the other hand, the embodiment of the invention provides a control plane network element, which has the function of realizing the control plane network element behavior in the method example. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

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

In yet 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 the user plane network element behavior in the foregoing method example. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

In one possible design, the structure of the user plane network element includes a processor and a communication interface, where the processor is configured to support the user plane network element to perform the 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 devices. Further, the user plane element may further comprise a memory for coupling with the processor, which holds the program instructions and data necessary for the user plane element.

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

In yet another aspect, an embodiment of the present invention provides a computer storage medium storing computer software instructions for use with the control plane network element described above, including a program designed to perform the above aspects.

In yet another aspect, an embodiment of the present invention provides a computer storage medium storing computer software instructions for use with the above-described network element for a user plane, which includes a program designed to perform the above-described 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, and the user plane tunnel is deleted when not needed to be used, so that the user plane tunnel is prevented from being stored 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 one possible network architecture provided by an embodiment of the present 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 schematic diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention;

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

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

fig. 6 is a communication schematic diagram of still 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 more clear, the technical solutions of the embodiments of the present invention will be described below with reference to the accompanying drawings in the embodiments of the present invention.

The network architecture and the service scenario described in the embodiments of the present invention are for more clearly describing the technical solution of the embodiments of the present invention, and do not constitute a limitation on the technical solution provided by the embodiments of the present invention, and those skilled in the art can know that, with the evolution of the network architecture and the appearance of the new service scenario, the technical solution provided by the embodiments of the present invention is applicable to similar technical problems.

Some possible application scenarios and network architectures to which the embodiments of the present invention are applicable are described below with reference to fig. 1A and 1B.

Fig. 1A shows an application scenario to which an embodiment of the present invention may be applied. As shown in fig. 1A, the terminal accesses an operator internet protocol (Internet Protocol, IP) service network, such as a multimedia subsystem (IP Multimedia System, IMS) network, a packet switched streaming service (Packet Switched Streaming Service, PSS) network, etc., through a radio access network and a core network. The technical solution described in the present invention may be applicable to long term evolution (Long Term Evolution, LTE) systems, or other wireless communication systems employing various wireless access technologies, such as systems employing access technologies such as code division multiple access (Code Division Multiple Access, CDMA), frequency division multiple access (Frequency Division Multiple Access, FDMA), time division multiple access (Time Division Multiple Access, TDMA), orthogonal frequency division multiple access (Orthogonal Frequency Division Multiple Access, OFDMA), single carrier frequency division multiple access (Single Carrier Frequency Division Multiple Access, SC-FDMA), and the like. In addition, the method can be also applied to a subsequent evolution system of an LTE system, a next generation network system, namely a fifth generation (5th Generation,5G) system and the like. For clarity, only the LTE system is described herein as an example. In the LTE system, an evolved universal terrestrial radio access network (Evolved Universal Terrestrial Radio Access Network, E-UTRAN) serves as a radio access network, and an evolved packet core network (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 scenario, fig. 1B shows a possible network architecture provided by an embodiment of the present invention. As shown in fig. 1B, the network architecture includes: control plane network element 110 and user plane network element 120.

The control plane network element 110 is a network device for implementing control plane functions. For example, control plane functions include management of radio resources, establishment of radio connections, quality of service (Quality of Service, qoS) guarantees for traffic, etc. The user plane network element 120 is a network device for implementing user plane functions. The user plane functions mainly include transmitting and receiving traffic 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. At least one user plane tunnel (user plane tunnel) is provided 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, at least one control plane tunnel (control plane tunnel) is provided 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: an access network device 130 and a terminal 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 employing different radio access technologies, the names of devices with base station functionality may vary, for example in LTE systems, referred to as evolved NodeB (eNB or eNodeB), in 3G communication systems, referred to as Node B (Node B), etc. For convenience of description, in the embodiment of the present invention, the above-mentioned devices for providing a wireless communication function for a terminal are collectively referred to as an access network device.

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

The access network device 130 and the terminal 140 communicate with each other via some air interface technology, for example via cellular technology. In addition, the access network device 130 and 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 access a Data Network (Data Network), such as a public Data Network (Public Data Network, PDN).

In the present embodiment, the terms "network" and "system" are often used interchangeably, but those skilled in the art will understand their meaning. In the embodiment of the present invention, there are many possible implementation forms of the control plane network element 110 and the user plane network element 120. For example, in an LTE system, the control plane network element 110 may be: SGW-C, PGW-C, control plane network element of traffic detection function (Traffic Detection Function, TDF) entity, SGW/PGW-C; the user plane network element 120 may be: the user plane network element and the SGW/PGW-U of the SGW-U, PGW-U, TDF entity, wherein the control plane network element and the user plane network element of the TDF entity can be respectively described as TDF-C and TDF-U. For another example, in the Next Generation network, the control plane element 110 may be a control plane element of the Next Generation Network (NG), and the user plane element 120 may be a user plane element of the Next Generation network, where the control plane element and the user plane element of the Next Generation network may be respectively described as NG-CP and NG-UP. 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 occur in the future, names of control plane network elements, user plane network elements, access network devices, terminals, etc. may change, but this does not affect implementation of the scheme of the embodiment of the present invention.

At present, in a scene of separating a control plane from a user plane, a user plane tunnel between a control plane network element and a user plane network element is reserved all the time under the condition of no data transmission, so that resource waste is caused. In view of this, the 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 the method. 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 accords with 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 arranged 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 tunnels correspond to terminal granularity, at least one user plane tunnel is provided between the control plane network element and the user plane network element, and each user plane tunnel in the at least one user plane tunnel is used for transmitting data related to one terminal. For another example, when the user plane tunnels correspond to the session granularity, at least one user plane tunnel is provided between the control plane network element and the user plane network element, and each user plane tunnel in the at least one user plane tunnel is used for transmitting data related to one session. For another example, when the user plane tunnels correspond to the bearer granularity, at least one user plane tunnel is provided between the control plane network element and the user plane network element, and each user plane tunnel in the at least one user plane tunnel is used for transmitting data related to one bearer.

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

A session may refer to a communication interaction between two devices during an uninterrupted, specific operating time. During a session, all messages transmitted between two devices belong to the session. In the embodiment of the invention, the session refers to communication interaction between the terminal and the network element in the data network for transmitting service data. Data associated with one terminal may be transmitted through at least one session.

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

The preset condition may refer to a preset 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 details on preset conditions see below.

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

In part 202, the control plane network element sends request information to the user plane network element, the request information being 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 following: the method comprises the steps of indicating information for indicating deletion of a user plane tunnel, identification of a target user plane tunnel, a message forwarding rule corresponding to the target user plane tunnel or a message matching rule corresponding to the target user plane tunnel.

In a possible implementation manner, the request information carries the identifier of the target user plane tunnel so as to inform the user plane network element of the target user plane tunnel to be deleted. For example, when the granularity corresponding to the user plane tunnel is the terminal granularity, the session granularity or the 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 request information needs to identify the 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 equipment granularity, only one user plane tunnel is arranged between the control plane network element and the user plane network element, so that the request information only needs to carry the indication information, and the request information does not need to carry the identifier of the one user plane tunnel.

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

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

Specifically, after receiving the request information, the user plane network element may determine a target user plane tunnel that needs to be deleted, and then delete the target user plane tunnel. For example, the user plane network element deleting the target user plane tunnel may be implemented by: releasing the resources occupied by the target user plane tunnel, deleting the 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, the response information indicating that the target user plane tunnel has been successfully deleted. Accordingly, after the control plane network element receives the response information from the user plane network element, it can be confirmed that the target user plane tunnel has been deleted.

It should be noted that, as already 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. Request information and response information can be received and transmitted between the control plane network element and the user plane network element through a 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 which accords with 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 the technical scheme for deleting the user plane tunnel between the control plane network element and the user plane network element is provided for the scene of separating the control plane from the user plane, and the user plane tunnel can be deleted when not needed to be used, so that the user plane tunnel is prevented from being long-term existing, and resources are saved.

The preset conditions according to the embodiment of the present invention are further described below with respect to different granularities corresponding to the user plane tunnel.

1. User plane tunnel corresponding terminal granularity

When the user plane tunnels correspond to terminal granularity, each user plane tunnel in 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:

(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 a plurality. These target terminal related sessions are used for transmitting target terminal related data. For example, the data related to the target terminal includes: and the target terminal sends uplink service data to a 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 are transmitted on the target user plane tunnel. When all sessions related to the target terminal need to be deleted, the data related to the target terminal is not required to be transmitted through the target user plane tunnel, and the deletion of the target user plane tunnel is triggered.

In one example, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. 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, assume that 2 sessions are established between the terminal 1 and network elements in the data network, when all the 2 sessions need to be deleted, the control plane network element determines to delete the user plane tunnel 1 corresponding to the terminal 1, sends request information carrying the identifier of the user plane tunnel 1 to the user plane network element, and deletes the user plane tunnel 1 after the user plane network element receives 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 cases: service interruption between the target terminal and a network element in the data network; target terminal detach process; in the target terminal attachment flow, the situation that the target terminal still has activated context in the control plane network element due to unreasonable detachment before is found; the update location of the target terminal in the tracking area update or routing area update procedure is rejected, etc.

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

In this case, the user plane tunnel may be deleted in the data buffering 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 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. And subsequently, when the target terminal is recovered from the idle state to the connection state, the control plane network element transmits the cached data related to the target terminal to the user plane network element, and the user plane network element transmits 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 can be allocated by the control plane network element, or can be allocated by other devices and notified to the control plane network element. For example, when the control plane network element is SGW-C, the maximum amount of buffering corresponding to each terminal may be allocated and notified to SGW-C by a mobility management entity (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 amount of buffering allocated to each different terminal may be the same or different, and the embodiment of the present invention is not limited thereto. Optionally, the maximum buffer amount is a downlink buffer recommended amount (downlink buffering suggested count). Taking the target terminal as an example, when the cached data related to the target terminal in the control plane network element reaches the maximum cache amount allocated for the target terminal, the control plane network element cannot continuously store the data related to the target terminal, and the user plane network element can not need to forward the data related to the target terminal 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, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. 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 amount of buffering allocated for terminal 1 is a. When the terminal 1 is in an idle state, 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 after receiving the data related to the terminal 1, and the control plane network element caches the data. When the cached data related to the terminal 1 in the control plane network element reaches the maximum cache quantity 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.

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

(c) The data related to the target terminal cached in the control plane network element is sent to the user plane network element entirely.

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

It has been described above that, 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 caches the data. And subsequently, when the target terminal is recovered from the idle state to the connection state, the control plane network element transmits the cached data related to the target terminal to the user plane network element, and the user plane network element transmits 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 is 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 can be deleted.

In one example, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. 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 recovered from an idle state to a connected state, the control plane network element sends the cached 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 all the data related to the terminal 1 cached in the control plane network element are 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.

For example, in the case of deleting a user plane tunnel in the data forwarding scenario, the control plane network element involved is SGW-C and the user plane network element is SGW-U, or the control plane network element involved is SGW/PGW-C and the user plane network element is SGW/PGW-U, or the control plane network element involved 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 interception of data related to the target terminal is no longer required.

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

In the legal monitoring scene, if the legal monitoring system needs to monitor 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 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 further include other data type information. The data forwarded by the control plane network element to the legal monitoring system may be data or other information processed by the control plane network element.

If the lawful interception system no longer needs to intercept the data related to the target terminal, the lawful interception system may send a lawful interception deactivation message to the control plane network element, where the lawful interception deactivation message is used to instruct to deactivate the lawful interception function related to the target terminal, 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 forward the data to the lawful interception system, where the target user plane tunnel may be deleted.

In one example, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. 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 legal monitoring system activates the legal monitoring function related to the terminal 1, the user plane network element sends 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 forwards the data to the legal monitoring system. After receiving a legal interception deactivation message sent by a legal interception system and used for indicating to deactivate a legal interception function related to the terminal 1, the control plane network element determines to delete the user plane tunnel 1 corresponding to the terminal 1, sends request information carrying the identifier of the user plane tunnel 1 to the user plane network element, and deletes the user plane tunnel 1 after the user plane network element receives the request information.

For example, in the case of deleting a user plane tunnel in a legal listening scenario, the control plane network element involved is SGW-C and the user plane network element is SGW-U, or the control plane network element involved is PGW-C and the user plane network element is PGW-U, or the control plane network element involved is SGW/PGW-C and the user plane network element is SGW/PGW-U, or the control plane network element involved is NG-CP and the user plane network element is NG-UP.

It should be noted that, when the granularity of the user plane tunnel corresponds to the granularity of the terminal, one terminal may correspond to one user plane tunnel, and in this case, the target user plane tunnel corresponding to the target terminal is one 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

When the user plane tunnels correspond to the session granularity, each user plane tunnel in 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 session. The target user plane tunnel is used to transport data related to the target session. The preset condition may include one of the following:

(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, the data related to the target session is not required to be transmitted through the target user plane tunnel, and the deletion of the target user plane tunnel is triggered.

In one example, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. 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 the user plane tunnel 1 corresponding to session 1, and sends request information carrying the identifier of user plane tunnel 1 to the user plane network element, and after receiving the request information, the user plane network element deletes user plane tunnel 1.

In addition, the reason why the target session needs to be deleted may include one of the following cases: service interruption between the target terminal and a network element in the data network; target terminal detach process; in the target terminal attachment flow, the situation that the target terminal still has activated context in the control plane network element due to unreasonable detachment before is found; the update location of the target terminal in the tracking area update or routing area update procedure is rejected, the session deletion procedure initiated by the target terminal or the network, etc. 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 that has been buffered in the control plane network element has reached a maximum amount of buffering 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 can be allocated by the control plane network element, or can be allocated by other devices and notified to the control plane network element. For example, when the control plane network element is SGW-C, the maximum buffer amount corresponding to each terminal may be allocated by MME and notified to 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 amount of buffering allocated to each different terminal may be the same or different, and the embodiment of the present invention is not limited thereto. Optionally, the maximum buffer amount is a downlink buffer recommended amount (downlink buffering suggested count). Taking the target terminal as an example, when the cached data related to the target terminal in the control plane network element reaches the maximum cache amount allocated for the target terminal, the control plane network element cannot continuously store the data related to the target terminal, and the user plane network element can not need to forward the data related to the target terminal 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 5 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5, respectively. 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. Assume that session 1, session 2, and session 3 are used to transmit data related to terminal 1, and session 4 and session 5 are used to transmit data related to terminal 2. Taking terminal 1 as an example, assume that the maximum amount of buffering allocated for 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 user plane tunnels of the user plane tunnels 1, 2 and 3, and the control plane network element caches the data. When the cached data related to the terminal 1 in the control plane network element reaches the maximum cache quantity a, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, and sends request information carrying the 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.

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

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, user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5, respectively. 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. Assume that session 1, session 2, and session 3 are used to transmit data related to terminal 1, and session 4 and session 5 are used to transmit data related to terminal 2. Taking the terminal 1 as an example, when the terminal 1 is recovered from an idle state to a connected state, the control plane network element sends the cached data related to the terminal 1 to the user plane network element through one or more user plane tunnels of the user plane tunnels 1, 2 and 3, and the user plane network element sends the data to the terminal 1. When all the data related to the terminal 1 cached in the control plane network element are 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, and sends request information carrying the 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.

(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 a 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, user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5, respectively. 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. Assume that session 1, session 2, and session 3 are used to transmit data related to terminal 1, and session 4 and session 5 are used to transmit 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 the data related to the terminal 1 to the control plane network element through one or more user plane tunnels of the user plane tunnels 1, 2 and 3, and the control plane network element forwards the data to the lawful interception system. After receiving a legal interception deactivation message sent by a legal interception system and used for indicating to deactivate a legal interception function related to the terminal 1, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, sends request information carrying the identifications of the user plane tunnels 1, 2 and 3 to the user plane network element, and deletes the user plane tunnels 1, 2 and 3 after receiving the request information.

3. User plane tunnel corresponding bearing granularity

When the user plane tunnels correspond to the bearing granularity, each user plane tunnel in 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 bearing. The target user plane tunnel is used to transport data related to the target bearer. The preset condition includes one of the following cases:

(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, the data related to the target session is not required to be transmitted through the target user plane tunnel, and the deletion of the target user plane tunnel is triggered.

In one example, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. 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. Suppose bearer 1 and bearer 2 are used to transport data related to session 1 and bearer 3 is used to transport data related to session 2. 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, and sends request information carrying identifiers of user plane tunnels 1 and 2 to the user plane network element, and after receiving the request information, the user plane network element deletes user plane tunnels 1 and 2.

In addition, the reason why the target session needs to be deleted may include one of the following cases: service interruption between the target terminal and a network element in the data network; target terminal detach process; in the attachment flow, the situation that the target terminal still has activated context in the control plane network element due to unreasonable detachment before is found; the update location of the target terminal in the tracking area update or routing area update procedure is rejected, the session deletion procedure initiated by the target terminal or the network, etc. 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 that has been buffered in the control plane network element has reached the maximum buffer size allocated for the target terminal.

When the target terminal is in an 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 (such as downlink service data sent to the target terminal by the network element in the data network), and the control plane network element caches the data. And subsequently, when the target terminal is recovered from the idle state to the connection state, the control plane network element transmits the cached data related to the target terminal to the user plane network element, and the user plane network element transmits 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, user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5, respectively. 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. Assuming that bearer 1, bearer 2 and bearer 3 are used to transmit data related to terminal 1, bearer 4 and bearer 5 are used to transmit data related to terminal 2. Taking terminal 1 as an example, assume that the maximum amount of buffering allocated for 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 user plane tunnels of the user plane tunnels 1, 2 and 3, and the control plane network element caches the data. When the cached data related to the terminal 1 in the control plane network element reaches the maximum cache quantity a, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, and sends request information carrying the 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.

(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 buffered in the control plane network element is sent to the user plane network element in its entirety.

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, user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5, respectively. 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. Assuming that bearer 1, bearer 2 and bearer 3 are used to transmit data related to terminal 1, bearer 4 and bearer 5 are used to transmit data related to terminal 2. Taking the terminal 1 as an example, when the terminal 1 is recovered from an idle state to a connected state, the control plane network element sends the cached data related to the terminal 1 to the user plane network element through one or more user plane tunnels of the user plane tunnels 1, 2 and 3, and the user plane network element sends the data to the terminal 1. When all the data related to the terminal 1 cached in the control plane network element are 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, and sends request information carrying the 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.

(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 a 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, user plane tunnel 1, user plane tunnel 2, user plane tunnel 3, user plane tunnel 4, and user plane tunnel 5, respectively. 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. Assuming that bearer 1, bearer 2 and bearer 3 are used to transmit data related to terminal 1, bearer 4 and bearer 5 are used to transmit 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 the data related to the terminal 1 to the control plane network element through one or more user plane tunnels of the user plane tunnels 1, 2 and 3, and the control plane network element forwards the data to the lawful interception system. After receiving a legal interception deactivation message sent by a legal interception system and used for indicating to deactivate a legal interception function related to the terminal 1, the control plane network element determines to delete the user plane tunnels 1, 2 and 3 corresponding to the terminal 1, sends request information carrying the identifications of the user plane tunnels 1, 2 and 3 to the user plane network element, and 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 equipment granularity, at least one user plane tunnel between the control plane network element and the user plane network element comprises a 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:

(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 over this one user plane tunnel. If only a portion of the session needs to be deleted, the user plane tunnel cannot be deleted for transmitting other undeleted session related data. When all the sessions need to be deleted, the session is not required to be transmitted on the user plane tunnel, and 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 that there are a total of 3 sessions between all terminals that are commonly served by 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 these 3 sessions is all tunneled through this 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 which is cached in the control plane network element and related to each terminal in all terminals reaches the maximum cache quantity allocated for each terminal.

For any terminal (taking a target terminal as an example) served by the control plane network element and the user plane network element together, when the target terminal is in an idle state, the user plane network element forwards the data related to the target terminal to the control plane network element through one user plane tunnel after receiving the data related to the target terminal (for example, downlink service data sent by the network element in the data network to the target terminal), and the control plane network element caches the data. Subsequently, when the target terminal is recovered 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 can be allocated by the control plane network element, or can be allocated by other devices and notified to the control plane network element. For example, when the control plane network element is SGW-C, the maximum buffer amount corresponding to each terminal may be allocated by MME and notified to 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 amount of buffering allocated to each different terminal may be the same or different, and the embodiment of the present invention is not limited thereto. Optionally, the maximum buffer amount is a downlink buffer recommended amount (downlink buffering suggested count). Taking the target terminal as an example, when the data related to the target terminal, which is cached in the control plane network element, reaches the maximum cache amount allocated to the target terminal, the control plane network element cannot continuously store the data related to the target terminal. Because there is only one user plane tunnel between the control plane network element and the user plane network element, the data related to each terminal is transmitted through the one user plane tunnel. If only some of the terminals have buffered data in the control plane network element that has reached their respective maximum buffer, then the user plane tunnel cannot be deleted for transmitting data related to other terminals that have not reached their maximum buffer. And triggering to delete the user plane tunnel when the cached data of all the terminals in the control plane network element reach the corresponding maximum cache quantity.

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 that the control plane network element and the user plane network element commonly serve include terminal 1, terminal 2, and terminal 3. Assuming that the maximum buffer capacity allocated to each terminal is a, when the buffered data related to each terminal in the control plane network element reaches the maximum buffer capacity a, the control plane network element determines to delete the one 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 one user plane tunnel after receiving the request information.

(c) The data related to each terminal in all terminals cached in the control plane network element are all sent to the user plane network element.

It has been described above that, 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 above-mentioned one user plane tunnel, and the control plane network element caches the data. Subsequently, when the target terminal is recovered 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.

Because there is only one user plane tunnel between the control plane network element and the user plane network element, the 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 has been sent to the user plane network element in its entirety, the one user plane tunnel cannot be deleted for transmitting data related to other terminals for which the data buffered in the control plane network element has not been sent to the user plane network element in its entirety. When all the data cached by all the terminals in the control plane network element are sent to the user plane network element, the user plane tunnel is triggered to be deleted.

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 that the control plane network element and the user plane network element commonly serve include terminal 1, terminal 2, and terminal 3. When all the data related to each terminal cached in the control plane network element are 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 indicating that it is no longer necessary to intercept data related to any of the above-mentioned terminals.

In the lawful interception scenario, if the lawful interception system needs to intercept data related to any terminal (for example, a target terminal), 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 one entry 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 further include other data type information. The data forwarded by the control plane network element to the legal monitoring system may be data or other information processed by the control plane network element.

If the lawful interception system no longer needs to intercept the data related to the target terminal, the lawful interception system may send a lawful interception deactivation message to the control plane network element, where the lawful interception deactivation message is used to instruct to deactivate the lawful interception function related to the target terminal, 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 forward 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 one user plane tunnel cannot be deleted for transmitting data related to these terminals. When the legal monitoring system no longer needs to monitor the data related to any terminal, the user plane tunnel is triggered to be deleted.

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 that the control plane network element and the user plane network element commonly serve include terminal 1, terminal 2, and terminal 3. When the legal monitoring system no longer needs to monitor the data related to any terminal, 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 described above for different granularities corresponding to the user plane tunnels. And 4 different application scenes such as session deletion, data caching, data forwarding, legal monitoring and the like are respectively introduced and explained for the preset conditions. For the data buffering scenario, the above only takes the allocation of the terminal corresponding to the maximum buffering amount as an example. In other possible implementations, the maximum amount of buffering may also correspond to the user plane tunnel allocation. That is, the control plane network element is configured with a maximum buffer amount allocated for each user plane tunnel. The maximum buffer capacity corresponding to each user plane tunnel can be allocated by the control plane network element, or can be allocated by other devices and notified to the control plane network element. For example, when the control plane network element is SGW-C, the maximum buffer size corresponding to each user plane tunnel may be allocated by MME and notified to SGW-C. The maximum buffer size allocated for the target user plane tunnel refers to the maximum amount of data received from the user plane network element through the target user plane tunnel that the control plane network element can buffer. When the number of the user plane tunnels is multiple, the maximum buffer amount allocated to each of the different user plane tunnels may be the same or different, which is not limited by 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 buffer size allocated for the target user plane tunnel. When the buffered data transmitted through the target user plane tunnel in the control plane network element reaches the maximum buffer capacity allocated for the target user plane tunnel, the control plane network element cannot continuously store the data received through the target user plane tunnel, and the user plane network element can not forward the data to the control plane network element for buffering through the target user plane tunnel, and the target user plane tunnel can be deleted.

In one example, assume that there are 3 user plane tunnels between the control plane network element and the user plane network element, user plane tunnel 1, user plane tunnel 2, and user plane tunnel 3, respectively. Assuming that the maximum buffer capacity allocated to each user plane tunnel is a, taking the user plane tunnel 1 as an example, when the data transmitted from the user plane network element to the control plane network element through the user plane tunnel 1 reaches the maximum buffer capacity a, the control plane network element determines to delete the user plane tunnel 1, and 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.

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

In an alternative embodiment provided based on the embodiment shown in fig. 2, before or after the control plane network element sends the request information to the user plane network element, i.e. before or after the part 202, the method may further include the following parts:

in 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 the control plane network element detects 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 to transmit data associated with one terminal when the user plane tunnel corresponds to the terminal granularity. The new user plane tunnel requested to be created is used for transmitting data related to the service 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: (a) session creation associated with a service terminal; (b) The service terminal is recovered from the idle state to the connection 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 an indication that the legal interception system needs to intercept data related to the service terminal.

2. User plane tunnel corresponding session granularity

Each user plane tunnel is used to transport data associated with one session when the user plane tunnels correspond to the granularity of the session. 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: (a) a new session needs to be created; (b) The new session includes at least one session for transmitting data related to the service terminal, and the service terminal is restored from the idle state to the 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 includes at least one session for transmitting data related to the service terminal, and the service terminal is converted from a connected state to an idle state, and the control plane network element needs to receive and buffer 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 service terminal and the control plane network element receives an indication of a lawful interception system that data related to the service terminal needs to be intercepted.

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

3. User plane tunnel corresponding bearing granularity

When the user plane tunnels correspond to the bearer granularity, each user plane tunnel is used for transmitting data related to one bearer. The new user plane tunnel requested to be created is used to transmit data related to a new bearer, which is a bearer that is not created temporarily. The creation condition may include one of the following: (a) The new bearer includes at least one bearer for transmitting data related to the new session, and the new session needs to be created, the new session being a session that 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 recovered 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 converted from a connection state to an idle state, and the control plane network element needs to receive and buffer 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 service terminal and the control plane network element receives an indication of a lawful interception system that data related to the service terminal needs to be intercepted.

4. User plane tunnel corresponding device granularity

When the user plane tunnel corresponds to the equipment granularity, because only one user plane tunnel is arranged between the control plane network element and the user plane network element, the new user plane tunnel which is required to be created is the user plane tunnel. The 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: (a) The session tunneled through the user plane 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 above terminals is recovered from an idle state to a connection 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 above terminals 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 terminal from the user plane network element; (d) The control plane network element receives an indication that the legal interception system needs to intercept data related to any one of the above terminals.

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

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

In one example, the creation request may carry at least one of: the method comprises the steps of indicating information for indicating the creation of a user plane tunnel, identification of a new user plane tunnel, a message forwarding rule corresponding to the new user plane tunnel or a message matching rule corresponding to the new user plane tunnel.

In one possible implementation manner, the creation request carries an identifier of the new user plane tunnel requested to be created, so as to inform the user plane network element that the new user plane tunnel needs to be created. For example, when the granularity corresponding to the user plane tunnel is the terminal granularity, the session granularity or the 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 for creating the request in the creation request besides carrying the indication information. For another example, when the granularity corresponding to the user plane tunnel is the device granularity, only one user plane tunnel is provided between the control plane network element and the user plane network element, so that the creation request only carries the indication information, and the creation request does not need to carry the identifier of the one user plane tunnel.

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

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

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

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

In addition, the control plane network element and the user plane network element can send and receive a creation request and a creation response through a 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 following further describes the scheme of the embodiment of the present invention based on the method shown in fig. 2 and 3 with reference to fig. 4 to 6. In the methods shown in fig. 4 to fig. 6, the same or similar content as the method shown in fig. 2 or fig. 3 may refer to the detailed description in fig. 2 or fig. 3, and the detailed description will be omitted.

Fig. 4 is a communication schematic 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 is illustrated by taking the application scenario as the data cache scenario as an example. The method may include the following.

In 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.

In part 402, the control plane network element caches data related to the target terminal.

In part 403, the control plane network element determines whether the buffered data associated with the target terminal has reached a maximum amount of buffering allocated for the target terminal.

In the portion 404, if the cached data related to the target terminal has reached the maximum cache amount allocated for 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 the 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.

At 406, the user plane element sends response information to the control plane element.

In part 407, when the target terminal is restored from the idle state to the connected state, the control plane network element determines that a new user plane tunnel needs to be created, where the new user plane tunnel is used to transmit the cached data related to the target terminal to the user plane network element.

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

In 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.

And then, the control plane network element can send the cached data related to 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, the session termination request being used to instruct the user plane network element to delete the session associated with the target terminal.

In part 412, the user plane network element deletes the session associated with the target terminal and deletes the user plane tunnel associated with the target terminal.

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

Fig. 5 is a communication schematic diagram of another method for deleting a user plane tunnel according to an embodiment of the present invention. In fig. 5, the granularity of the terminal corresponding to the user plane tunnel is illustrated by taking the application scenario as the data forwarding scenario as an example. 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 transmits 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.

In part 502, the control plane network element determines whether the cached data associated with the target terminal has been sent entirely to the user plane network element.

In 503, if all the data related to the target terminal cached by the control plane network element is 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 the identifier of the target user plane tunnel.

In part 504, the user plane network element deletes the target user plane tunnel based on the request information.

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 element determines that a new user plane tunnel is to be created, which is used to receive data related to the target terminal from the user plane element, so as to buffer the data related to the target terminal in the control plane element, at 506.

In 507 part, the control plane network element sends a creation request to the user plane network element, the creation request being 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 based on the creation request.

In section 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, the session termination request being used to instruct the user plane network element to delete the session associated with the target terminal.

In section 511, the user plane network element deletes the session associated with the target terminal and deletes the user plane tunnel associated with the target terminal.

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

Fig. 6 is a communication schematic 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 is illustrated by taking the application scenario as the legal monitoring scenario as an example. The method may include the following.

In 601, in the case that the legal monitoring function corresponding to the target terminal is in an active 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.

In 602, the control plane network element forwards data related to 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, the lawful interception deactivation message being used to instruct to deactivate a lawful interception function associated with 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 information.

At 606, the user plane network element sends response information to the control plane network element.

In 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 indicate to activate a lawful interception function related to the target terminal.

At 608, the control plane network element sends a creation request to the user plane network element, the creation request being for instructing the user plane network element to create a new user plane tunnel for receiving data related to the target terminal from the user plane network element.

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

At 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 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 forwards the data related to the target terminal to the legal monitoring system.

In 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 related to the target terminal.

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

In part 613, the user plane network element sends a session termination response to the control plane network element.

The scheme provided by the embodiment of the invention is mainly introduced from the interaction angle of the control plane network element and the user plane network element. It will be appreciated that, in order to achieve the above-mentioned functions, the control plane network element and the user plane network element include corresponding hardware structures and/or software modules for performing the respective functions. The various illustrative units and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or a combination of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Those skilled in the art may implement the described functionality using different approaches for each particular application, but such implementation is not to be considered as beyond the scope of the embodiments of the present invention.

The embodiment of the invention can divide the functional units of the control plane network element or the user plane network element according to the method example, for example, each functional unit can be divided corresponding to each function, and two or more functions can be integrated in one processing unit. The integrated units may be implemented in hardware or in software functional units. It should be noted that, in the embodiment of the present invention, the division of the units is schematic, which is merely a logic function division, and other division manners may be implemented in actual practice.

In case of an integrated unit, fig. 7A shows a schematic diagram of one possible structure 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 the processes 201 and 202 in fig. 2, the processes 204 and 205 in fig. 3, the processes 402-404, 407, 408 and 411 in fig. 4, the processes 501-503, 506, 507 and 510 in fig. 5, the processes 602-604, 607, 608 and 611 in fig. 6, and/or other processes for the techniques described herein. The communication unit 703 is configured to support communication between the control plane network element and the user plane network element or other network entities. The control plane network element 700 may further comprise a storage unit 701 for storing program code and data of the control plane network element 700.

The processing unit 702 may be a processor or controller, such as a central processing unit (Central Processing Unit, CPU), a general purpose processor, a digital signal processor (Digital Signal Processor, DSP), an Application-specific integrated circuit (ASIC), a field programmable gate array (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 exemplary logic blocks, modules and circuits described in connection with this disclosure. The processor may also be a combination that performs the function of a computation, e.g., a combination comprising one or more microprocessors, a combination of a DSP and a microprocessor, and the like. The communication unit 703 may be a communication interface, a transceiver, a transceiving circuit, etc., where the communication interface is collectively referred to and may include one or more interfaces, for example, an interface between a control plane network element and a user plane network element. The storage 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 related to the embodiment of the present invention may be a 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 also include a bus 714. Wherein the communication interface 713, the processor 712, and the memory 711 may be interconnected by a bus 714; bus 714 may be a peripheral component interconnect standard (Peripheral Component Interconnect, PCI) bus, or an extended industry standard architecture (Extended Industry Standard Architecture, EISA) bus, among others. The bus 714 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. 7B, but not only one bus or one 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 an integrated unit, fig. 8A shows a schematic diagram of one possible structure of the user plane network element involved in the above embodiment. The user plane network element 800 comprises: a processing unit 802 and a communication unit 803. The processing unit 802 is configured to control and manage actions of the user plane network element, e.g., the processing unit 802 is configured to support the user plane network element to perform the process 203 in fig. 2, the process 206 in fig. 3, the processes 401, 405, 406, 409, 410, 412, and 413 in fig. 4, the processes 504, 505, 508, 509, 511, and 512 in fig. 5, the 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 the user plane network element and the control plane network element or other network entities. The user plane network element 800 may further comprise a storage unit 801 for storing program code and data of the user plane network element 800.

The processing unit 802 may be a processor or controller, such as a CPU, general-purpose processor, DSP, ASIC, FPGA, or other programmable logic device, transistor logic device, hardware component, or any combination thereof. Which may implement or perform the various exemplary logic blocks, modules and circuits described in connection with this disclosure. The processor may also be a combination that performs the function of a computation, e.g., a combination comprising one or more microprocessors, a combination of a DSP and a microprocessor, and the like. The communication unit 803 may be a communication interface, a transceiver, a transceiving circuit, etc., wherein the communication interface is collectively referred to and may comprise one or more interfaces, for example 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 a user plane network element shown in fig. 8B.

Referring to fig. 8B, the user plane network element 810 includes: processor 812, communication interface 813, memory 811. Optionally, the user plane network element 810 may also include a bus 814. Wherein communication interface 813, processor 812 and memory 811 may be interconnected by bus 814; bus 814 may be a PCI bus, an EISA bus, or the like. The bus 814 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. 8B, but not only one bus or one type of bus.

The user plane network elements shown in 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 present disclosure may be embodied in hardware, or may be embodied in software instructions executed by a processor. The software instructions may be comprised of corresponding software modules that may be stored in random access Memory (Random Access Memory, RAM), flash Memory, read Only Memory (ROM), erasable programmable Read Only Memory (Erasable Programmable ROM), electrically Erasable Programmable Read Only Memory (EEPROM), registers, 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. In the alternative, the storage medium may 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. It is of course also possible that the processor and the storage medium reside as discrete components in a control plane network element or a user plane network element.

Those skilled in the art will appreciate that in one or more of the examples described above, the functions described in the embodiments of the present invention may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, these 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 foregoing detailed description of the embodiments of the present invention further illustrates the purposes, technical solutions and advantageous effects of the embodiments of the present invention, and it should be understood that the foregoing description is only a specific implementation of the embodiments of the present invention, and is not intended to limit the scope of the embodiments of the present invention, and any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present invention should be included in the scope of the embodiments of the present invention.

Claims

1. A method for deleting a user plane tunnel, the method comprising:

the control plane network element determines that a target user plane tunnel which accords with a preset condition exists in at least one user plane tunnel between the control plane network element and the user plane network element; wherein the target user plane tunnel is one or more user plane tunnels in the at least one user plane tunnel;

and 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.

2. The method of claim 1, wherein each of the at least one user plane tunnel is configured to transmit data associated with one terminal, wherein the target user plane tunnel is configured to transmit data associated with a target terminal, and wherein the preset condition includes one of:

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

the data which is cached in the control surface network element and related to the target terminal reaches the maximum cache quantity allocated for the target terminal;

the data which is cached in the control plane network element and 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, where the indication is used to indicate that data related to the target terminal no longer needs to be monitored.

3. The method according to claim 2, wherein the reason why all sessions related to the target terminal need to be deleted includes one of the following cases:

a service interruption between the target terminal and a network element in the data network;

the target terminal initiates a detach process; or alternatively

The update location of the target terminal in the tracking area update or routing area update procedure is rejected.

4. The method of claim 1, wherein each of the at least one user plane tunnel is configured to transmit data associated with a session, wherein the target user plane tunnel is configured to transmit data associated with a target session, and wherein the preset condition comprises one of:

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 cache amount allocated for 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 sent to the user plane network element;

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 a lawful interception system indicating that it is no longer necessary to intercept data related to the target terminal.

5. The method of claim 1, wherein each of the at least one user plane tunnel is configured to transmit data associated with one bearer, wherein the target user plane tunnel is configured to transmit data associated with a target bearer, and wherein the preset condition comprises one of:

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 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 cache amount allocated for 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 sent to the user plane network element;

the target bearer is at least one bearer for transmitting data related to a target terminal, and the control plane network element receives an indication of a lawful interception system, the indication indicating that interception of data related to the target terminal is no longer required.

6. The method of claim 4, wherein the reason why the target session needs to be deleted comprises one of:

service interruption between the target terminal and a network element in the data network;

the target terminal detach process;

the updating position of the target terminal in the tracking area updating or routing area updating process is refused;

the target terminal or the network initiates a session deletion flow aiming at the target session;

wherein the target session is a session between the target terminal and a network element of the data network.

7. The method according to claim 1, wherein the at least one user plane tunnel comprises one user plane tunnel, 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, and the preset condition comprises one of the following situations:

All sessions tunneled through the one user plane need to be deleted;

the data which are cached in the control surface network element and related to each terminal in all the terminals reach the maximum cache quantity distributed for each terminal;

the data which is cached in the control plane network element and 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, where the indication is used to indicate that data related to any one of the all terminals no longer needs to be monitored.

8. The method according to claim 1, wherein 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 buffer size allocated for the target user plane tunnel.

9. The method according to any of claims 1 to 8, 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;

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 the new user plane tunnel.

10. The method according to any one of claims 1 to 8, wherein the request information may carry at least one of the following: the method comprises the steps of indicating information for indicating deletion of a user plane tunnel, identification of a target user plane tunnel, a message forwarding rule corresponding to the target user plane tunnel or a message matching rule corresponding to the target user plane tunnel.

11. The method according to any of claims 1 to 8, wherein at least one control plane tunnel is comprised between the control plane network element and the user plane network element;

and the control plane network element sends the request information through the at least one control plane tunnel.

12. A method for deleting a user plane tunnel, the method comprising:

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

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

13. The method of claim 12, wherein each of the at least one user plane tunnel is configured to transmit data associated with one terminal, wherein the target user plane tunnel is configured to transmit data associated with a target terminal, and wherein the preset condition includes one of:

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

14. The method of claim 12, wherein each of the at least one user plane tunnel is configured to transmit data associated with a session, wherein the target user plane tunnel is configured to transmit data associated with a target session, and wherein the preset condition comprises one of:

the target session needs to be deleted;

15. The method of claim 12, wherein each of the at least one user plane tunnel is configured to transmit data associated with one bearer, wherein the target user plane tunnel is configured to transmit data associated with a target bearer, and wherein the preset condition comprises one of:

16. The method according to claim 12, wherein the at least one user plane tunnel comprises one user plane tunnel, 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, and the preset condition comprises one of:

all sessions tunneled through the one user plane need to be deleted;

17. The method according to claim 12, wherein the preset condition is: 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 size allocated for the target user plane tunnel.

18. The method according to any of claims 12 to 17, wherein the user plane network element is arranged to, before or after receiving the request information from the control plane network element, further comprise:

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.

19. The method according to any of claims 12 to 17, wherein said deleting the target user plane tunnel comprises:

and releasing the resources occupied by the target user plane tunnel or deleting the context information corresponding to the target user plane tunnel.

20. The method according to any of claims 12 to 17, wherein at least one control plane tunnel is comprised between the user plane network element and the control plane network element;

And the user plane network element receives the request information through the at least one control plane tunnel.

21. A control plane network element comprising means for implementing the method of any of the preceding claims 1-11.

22. A user plane network element comprising means for implementing the method of any of the preceding claims 12-20.

23. A communication device comprising a memory and a processor, wherein,

the memory is configured to store a program, and the processor is configured to execute the program stored in the memory to implement the method according to any one of claims 1 to 20.

24. A computer readable storage medium comprising instructions which, when executed by a processor, implement the method of any of claims 1-20.