CN110913506A

CN110913506A - Downlink data caching method, UPF entity and AMF entity

Info

Publication number: CN110913506A
Application number: CN201811076397.7A
Authority: CN
Inventors: 邓强
Original assignee: China Academy of Telecommunications Technology CATT
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2018-09-14
Filing date: 2018-09-14
Publication date: 2020-03-24
Anticipated expiration: 2038-09-14
Also published as: CN110913506B

Abstract

The invention discloses a downlink data caching method, a UPF entity and an AMF entity, which are used for providing a new downlink data caching method so as to solve the problem of how to cache downlink data when UE is in an RRC Inactive state and an eDRX mechanism is used. The downlink data caching method comprises the following steps: a User Plane Function (UPF) entity receives a first indication message from an access and mobility management function (AMF) entity, wherein the first indication message is used for indicating that a terminal device uses an extended discontinuous reception (eDRX) mechanism; when receiving downlink data, the UPF entity sends a first request message to the AMF entity, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state; and the UPF entity receives the second indication message from the AMF entity and caches the downlink data when the terminal equipment is determined to be in the unreachable state based on the second indication message.

Description

Downlink data caching method, UPF entity and AMF entity

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method for caching downlink data, a UPF entity, and an AMF entity.

Background

The 3rd Generation Partnership Project (3 GPP) R15 defines a new state of a terminal device, such as a User Equipment (UE), and a Radio Resource Control Inactive (RRC Inactive) state. When the UE is in the RRC Inactive state, an air interface RRC connection and a Data Radio Bearer (DRB) of the UE are released, a user plane connection and a control plane connection between a Radio Access Network (RAN) and a core Network are maintained, and a UE context is stored on the UE side and the RAN side.

When UE needs to send uplink data or respond to RAN paging, it will initiate the Resume process and establish RRC connection and DRB. Compared with the mode that the UE enters the CONNECTED state from the IDLE state, the mode that the UE enters the RRC CONNECTED state from the RRC Inactive state uses less signaling, and the signaling load of the UE and the network is relieved. When downlink data reaches a User Plane Function (UPF) entity, the UPF entity directly sends the data to RAN, RAN performs paging on UE, the UE responds to the paging to initiate a Resume process to establish RRC connection and DRB, the UE enters an RRC CONNECTED state from an RRC Inactive state, and the RAN receives the downlink data.

For Cellular Internet of Things (Cellular Internet of Things, CIoT) UE, energy saving is an important objective, an extended Discontinuous Reception (eDRX) mechanism is defined in the standard, and in each eDRX cycle, the UE may respond to Paging only within a Paging Time Window (PTW) Time, and the UE closes the AS layer at other times and stops responding to the Paging, so AS to achieve the purpose of saving power, and at this Time, downlink data cannot be directly sent to the UE. Therefore, when the UE is in the RRC Inactive state and the eDRX mechanism is used, there is no way to buffer the downlink data.

Disclosure of Invention

The embodiment of the invention provides a downlink data caching method, a UPF entity and an AMF entity, which are used for providing a new downlink data caching method so as to solve the problem of how to cache downlink data when UE is in an RRC Inactive state and an eDRX mechanism is used.

In a first aspect, a downlink data caching method is provided, where the caching method includes:

a User Plane Function (UPF) entity receives a first indication message from an access and mobility management function (AMF) entity, wherein the first indication message is used for indicating that a terminal device uses an extended discontinuous reception (eDRX) mechanism;

the UPF entity sends a first request message to the AMF entity when receiving downlink data, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state;

and the UPF entity receives a second indication message from the AMF entity, and caches downlink data when the terminal equipment is determined to be in an unreachable state based on the second indication message.

In the embodiment of the invention, the AMF entity can know whether the terminal equipment is in an RRC Inactive state and starts an eDRX mechanism according to an eDRX parameter requested by the terminal equipment, so that when the terminal equipment is in the RRC Inactive state and starts the eDRX mechanism, the UPF entity is informed that the terminal equipment starts the eDRX mechanism, and thus the UPF entity requests the AMF entity to inquire whether the terminal equipment can reach or not, and the received downlink data is cached.

Optionally, the receiving, by the user plane function UPF entity, the first indication message from the access and mobility management function AMF entity includes:

and the UPF entity receives the first indication message forwarded by the AMF entity through a Session Management Function (SMF) entity.

Optionally, the receiving, by the UPF entity, the first indication message forwarded by the AMF entity through the session management function, SMF entity, includes:

the UPF entity receives the first indication message forwarded by the SMF in the registration process of the terminal equipment from the AMF entity;

or the like, or, alternatively,

and the UPF entity receives the first indication message forwarded by the SMF entity from the AMF entity in the process of establishing a Protocol Data Unit (PDU) session by the terminal equipment.

In the embodiment of the invention, two modes of how the AMF entity informs the UPF entity whether the terminal equipment starts the eDRX mechanism are provided. For example, the AMF entity may notify the UPF entity through the SMF entity in the terminal device registration process or in the PDU session establishment process, and in any manner, the notification of the UPF entity whether the terminal device enables the eDRX mechanism may be implemented, and the usage scenario is relatively wide.

Optionally, when receiving the downlink data, the UPF entity sends a first request message to the AMF entity, where the first request message includes:

and when receiving the downlink data, the UPF entity sends the first request message to a Session Management Function (SMF) entity so as to send the first request message to the AMF entity through the SMF entity.

In the embodiment of the invention, the UPF entity requests the AMF entity to inquire whether the terminal equipment can be reached or not when receiving the downlink data, thereby determining whether to cache the downlink data or not, and sending the downlink data to the RAN when the cache is not needed, and ensuring the normal operation of the service.

Optionally, the method further includes:

and the UPF entity sends the received downlink data to a Radio Access Network (RAN) when determining that the received second indication message from the AMF entity indicates that the terminal equipment is in a reachable state.

Optionally, the caching the downlink data by the UPF entity when it is determined that the received second indication message from the AMF entity indicates that the terminal device is in the unreachable state, where the caching the downlink data by the UPF entity includes:

and the UPF entity caches the downlink data according to the downlink data caching information.

In the embodiment of the invention, the AMF entity can send the cache information to the UPF entity when determining that the terminal equipment is in the unreachable state, so that the UPF entity caches the downlink data according to the cache information, and the requirement of the AMF entity is met.

In a second aspect, a downlink data caching method is provided, where the caching method includes:

an access and mobility management function (AMF) entity sends a first indication message to a User Plane Function (UPF) entity, wherein the first indication message is used for indicating that a terminal device uses an extended discontinuous reception (eDRX) mechanism;

the AMF entity receives a first request message from the UPF entity, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state;

and the AMF entity sends a second indication message to the UPF entity, wherein the second indication message is used for indicating the state of the terminal equipment, so that the UPF entity caches the received downlink data according to the second indication message.

In the embodiment of the invention, the AMF entity can know whether the terminal equipment is in an RRC Inactive state and starts an eDRX mechanism according to an eDRX parameter requested by the terminal equipment, so that the UPF entity is informed that the terminal equipment starts the eDRX mechanism when the terminal equipment is in the RRC Inactive state and starts the eDRX mechanism. Thus, the AMF entity may instruct the UPF entity to cache the received downlink data according to the request of the UPF entity.

Optionally, the sending, by the access and mobility management function AMF entity, the first indication message to the user plane function UPF entity includes:

the AMF entity sends the first indication message to a Session Management Function (SMF) entity so as to send the first indication message to the UPF entity through the SMF entity.

Optionally, the first indication message sent by the AMF entity to the session management function SMF entity includes:

the AMF entity sends the first indication message to the SMF entity in the registration process of the terminal equipment;

or the like, or, alternatively,

and the AMF entity sends the first indication message to the SMF in the process of establishing a Protocol Data Unit (PDU) session by the terminal equipment.

Optionally, before the access and mobility management function AMF entity sends the first indication message to the user plane function UPF entity, the method further includes:

the AMF entity receives a second request message from the terminal equipment, wherein the second request message is used for requesting eDRX parameters from the AMF entity;

and the AMF entity sends the determined eDRX parameters to the terminal equipment.

In the embodiment of the invention, the AMF entity determines the eDRX parameter according to the application requirement of the terminal equipment, thereby ensuring the energy-saving effect of the terminal equipment as much as possible.

Optionally, the second indication message carries cache information of downlink data, so that the UPF entity caches the downlink data according to the cache information.

In a third aspect, a user plane function, UPF, entity is provided, where the UPF entity includes:

a memory to store instructions;

a processor for reading the instructions in the memory, performing the following processes:

receiving a first indication message from an access and mobility management function (AMF) entity, wherein the first indication message is used for indicating that an extended discontinuous reception (eDRX) mechanism is used by a terminal device; when receiving downlink data, sending a first request message to the AMF entity, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state; receiving a second indication message from the AMF entity, and caching downlink data when the terminal equipment is determined to be in an unreachable state based on the second indication message;

a transceiver for transceiving data under control of the processor.

Optionally, the processor is specifically configured to:

receiving, by the transceiver, the first indication message forwarded by the AMF entity through a Session Management Function (SMF) entity.

Optionally, the processor is specifically configured to:

receiving, by the transceiver, the first indication message forwarded by the SMF from the AMF entity during registration of the terminal device;

or the like, or, alternatively,

and receiving, by the transceiver, the first indication message forwarded by the SMF entity from the AMF entity in a process of establishing a protocol data unit, PDU, session by the terminal device.

Optionally, the processor is specifically configured to:

and when the downlink data is received, sending the first request message to a Session Management Function (SMF) entity through the transceiver, so as to send the first request message to the AMF entity through the SMF entity.

Optionally, the processor is further configured to:

and when the received second indication message from the AMF entity indicates that the terminal equipment is in the reachable state, sending the received downlink data to a Radio Access Network (RAN) through the transceiver.

Optionally, the second indication message carries downlink data caching information, and the caching unit is specifically configured to:

and caching the downlink data according to the downlink data caching information.

The technical effect of the UPF entity provided in the embodiment of the present invention may refer to the technical effect of the downlink data caching method provided in the first aspect, and is not described herein again.

In a fourth aspect, there is provided an access and mobility management function, AMF, entity, the AMF entity comprising:

a memory to store instructions;

sending a first indication message to a User Plane Function (UPF) entity, wherein the first indication message is used for indicating that a terminal device uses an extended discontinuous reception (eDRX) mechanism; receiving a first request message from the UPF entity, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state; sending a second indication message to the UPF entity, wherein the second indication message is used for indicating the state of the terminal equipment, so that the UPF entity caches the received downlink data according to the second indication message;

a transceiver for transceiving data under control of the processor.

Optionally, the processor is specifically configured to:

the first indication message is sent to a Session Management Function (SMF) entity through the transceiver, so that the first indication message is sent to the UPF entity through the SMF entity.

Optionally, the processor is specifically configured to:

in the registration process of the terminal equipment, the first indication message is sent to the SMF entity through the transceiver;

or the like, or, alternatively,

and in the process of establishing a Protocol Data Unit (PDU) session by the terminal equipment, the transceiver sends the first indication message to the SMF.

Optionally, the processor is further configured to:

receiving a second request message from the terminal device through the transceiver, wherein the second request message is used for requesting eDRX parameters from the AMF entity;

and sending the determined eDRX parameter to the terminal equipment through the transceiver.

The technical effect of the AMF entity provided in the embodiment of the present invention may refer to the technical effect of the downlink data caching method provided in the second aspect, and is not described herein again.

In a fifth aspect, a user plane function, UPF, entity is provided, the UPF entity comprising:

a receiving unit, configured to receive a first indication message from an access and mobility management function, AMF, entity, wherein the first indication message is used to indicate that an extended discontinuous reception, eDRX, mechanism is used by a terminal device;

a sending unit, configured to send a first request message to the AMF entity when receiving downlink data, where the first request message is used to request the AMF entity to query whether the terminal device is in a reachable state;

and the buffer unit is used for receiving the second indication message from the AMF entity and buffering the downlink data when the terminal equipment is determined to be in the unreachable state based on the second indication message.

Optionally, the receiving unit is specifically configured to:

receiving the first indication message forwarded by the AMF entity through a Session Management Function (SMF) entity.

Optionally, the receiving unit is specifically configured to:

receiving the first indication message forwarded by the SMF from the AMF entity in the registration process of the terminal equipment;

or the like, or, alternatively,

and receiving the first indication message forwarded by the SMF entity from the AMF entity in the process of establishing a Protocol Data Unit (PDU) session by the terminal equipment.

Optionally, the sending unit is specifically configured to:

and when the downlink data is received, sending the first request message to a Session Management Function (SMF) entity so as to send the first request message to the AMF entity through the SMF entity.

Optionally, the sending unit is further configured to:

and when determining that the received second indication message from the AMF entity indicates that the terminal equipment is in the reachable state, sending the received downlink data to a Radio Access Network (RAN).

In a sixth aspect, there is provided an access and mobility management function, AMF, entity, the AMF entity comprising:

a first sending unit, configured to send a first indication message to a User Plane Function (UPF) entity, where the first indication message is used to indicate that an extended discontinuous reception (eDRX) mechanism is used by a terminal device;

a receiving unit, configured to receive a first request message from the UPF entity, where the first request message is used to request the AMF entity to query whether the terminal device is in a reachable state;

a second sending unit, configured to send a second indication message to the UPF entity, where the second indication message is used to indicate a state of the terminal device, so that the UPF entity buffers the received downlink data according to the second indication message.

Optionally, the first sending unit is specifically configured to:

the first indication message is sent to a Session Management Function (SMF) entity, so that the SMF entity sends the first indication message to the UPF entity.

Optionally, the first sending unit is specifically configured to:

in the registration process of the terminal equipment, the first indication message is sent to the SMF entity;

or the like, or, alternatively,

and in the process of establishing a Protocol Data Unit (PDU) session by the terminal equipment, sending the first indication message to the SMF.

Optionally, the receiving unit is further configured to:

receiving a second request message from the terminal device, wherein the second request message is used for requesting eDRX parameters from the AMF entity;

the second sending unit is configured to send the determined eDRX parameter to the terminal device.

In a seventh aspect, a computer storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the method according to any of the first or second aspects.

In the embodiment of the invention, the AMF entity can know whether the terminal equipment is in an RRC Inactive state and starts an eDRX mechanism according to the eDRX requested by the terminal equipment, so that the UPF entity is informed that the terminal equipment starts the eDRX mechanism when the terminal equipment is in the RRC Inactive state and starts the eDRX mechanism. Thus, the AMF entity may instruct the UPF entity to cache the received downlink data according to the request of the UPF entity.

Drawings

Fig. 1 is a schematic flow chart of a downlink data caching method provided in the prior art;

fig. 2 is a schematic flow chart of a downlink data caching method according to an embodiment of the present invention;

fig. 3 is a flowchart illustrating an AMF entity indicating whether an updf entity UE enables an eDRX mechanism according to an embodiment of the present invention;

fig. 4 is a flowchart illustrating an AMF entity indicating whether an updf entity UE enables an eDRX mechanism according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a downlink data transmission process according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a UPF entity according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a UPF entity according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of an AMF entity according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of an AMF entity according to an embodiment of the present invention.

Detailed Description

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

In each eDRX cycle, the UE may respond to the Paging only within the Paging Time Window (PTW), and the UE may close the AS layer and stop responding to the Paging at other times, so AS to achieve the purpose of power saving, and at this Time, the downlink data may not be directly sent to the UE.

In contrast, in the R165G CIoT research project, when the UE is in the RRC Inactive state and uses the eDRX mechanism, the prior art provides a downlink data caching method, that is, when the UE enters the RRC Inactive state and uses the eDRX mechanism, the RAN requests the UPF entity to cache downlink data; and when the UE is reachable, the RAN informs the UPF entity that the UE is reachable, and the UPF sends the downlink data to the RAN. And when the UE is not reachable, the UPF entity caches the downlink data.

Specifically, please refer to fig. 1, which is a schematic flow chart of a downlink data caching method provided in the prior art, and a specific flow chart is as follows.

S101, based on local configuration, when UE enters RRC Inactive state and UE uses eDRX mechanism, RAN sends N2 notification message to AMF entity and sends buffer information. And the AMF entity receives the N2 notification message, and notifies the UPF entity to cache the downlink data.

S102, the UPF entity receives the downlink data from the application server and starts data caching.

S103, the UPF entity sends a Downlink Data Notification (DDN) message to the SMF entity. The SMF entity requests reachability information of the UE from the AMF entity.

S104, the AMF entity requests reachability information of the UE to the RAN through an N2 notification message notification process, if the UE is not reachable currently, the RAN provides new cache information to the AMF entity, and the RAN pages the UE at the next paging time of the UE. And the RAN sends a paging message to the UE when the UE can receive paging.

S105, the AMF entity informs the UPF entity of the reachability information of the UE, if the UE is reachable currently, the downlink data is sent to the UE, and if the UE is not reachable currently, the AMF entity provides new cache information for the UPF entity. When the UE responds to the paging or the UE actively sends uplink data, the UE initiates an RRC Resume process, the RAN informs the AMF entity that the UE is reachable, and the AMF entity informs the UPF entity that the UE is reachable. If the UE does not contact the network before the timer expires, the UPF will discard the buffered data. The RAN puts the UE into RRC Inactive state.

The caching method shown in fig. 1 is that the UPF entity requests the RAN to acquire the reachability information of the UE when receiving downlink data, that is, a large number of signaling procedures are used to make the UPF entity acquire the reachability information of the UE from the RAN, which results in a large network signaling load. In addition, the buffering information provided by the RAN to the UPF entity in step S101 is not accurate, for example, when the downlink data reaches the UPF entity in step S102, the UE is not necessarily in an unreachable state, and if the UE is in a reachable state, the signaling is wasted by performing steps S103 to S105.

In view of this, the embodiment of the present invention provides a new downlink data caching method, in which an AMF entity may learn whether a terminal device is in an RRC Inactive state and activates an eDRX mechanism according to an eDRX parameter requested by the terminal device, so as to notify a UPF entity that the terminal device activates the eDRX mechanism when the terminal device is in the RRC Inactive state and activates the eDRX mechanism. Thus, the AMF entity may instruct the UPF entity to cache the received downlink data according to the request of the UPF entity. Therefore, in the embodiment of the invention, when the terminal equipment is in the RRC Inactive state and the eDRX mechanism is started, the UPF entity is indicated to buffer the received downlink data, so that fewer signaling are used, and the network signaling load is reduced.

The terminal device according to the embodiments of the present invention may be a device providing voice and/or data connectivity to a user, a handheld device having a wireless connection function, or another processing device connected to a wireless modem. Wireless user equipment, which may be mobile terminals such as mobile telephones (or "cellular" telephones) and computers having mobile terminals, for example, portable, pocket, hand-held, computer-included, or vehicle-mounted mobile devices, may communicate with one or more core networks via a Radio Access Network (RAN). Examples of such devices include Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), and the like. A Terminal may also be referred to as a system, a Subscriber Unit (Subscriber Unit), a Subscriber Station (Subscriber Station), a Mobile Station (Mobile), a Remote Station (Remote Station), an Access Point (Access Point), a Remote Terminal (Remote Terminal), an Access Terminal (Access Terminal), a User Terminal (User Terminal), a User agent (User agent), a User Device (User Device), and a wireless Device (wireless Device). For convenience of description, the terminal device is hereinafter exemplified as a UE.

The technical scheme provided by the embodiment of the invention is described in the following with the accompanying drawings of the specification.

Referring to fig. 2, an embodiment of the present invention provides a downlink data caching method, and a flow of the method is described as follows. Since the downlink data caching method involves the interaction process between the AMF entity and the UPF entity as well as the SMF entity, the processes executed by the AMF entity and the UPF entity as well as the SMF entity will be described together in the following description of the flow.

S201, the UPF entity receives a first indication message from the AMF entity, wherein the first indication message is used for indicating that the terminal equipment uses an eDRX mechanism.

In the embodiment of the invention, the AMF entity can control the UPF to cache the downlink data, and when the UE closes the AS layer and stops responding to the paging in each eDRX period except for the PTW, the downlink data cannot be directly sent to the UE. During the PTW time, the downlink data can be directly sent to the UE. Therefore, when determining that it may be necessary to cause the UPF entity to buffer the downlink data, the AMF may send a first indication message to the UPF entity, where the first indication message is used to indicate that the terminal device uses the eDRX mechanism, so as to notify that the UPF entity may not directly send the downlink data to the UE and needs to buffer the downlink data.

The AMF entity sends the first indication message to the UPF entity, which may include, but is not limited to, the following two ways:

the first mode is as follows: the AMF entity may forward the first indication message to the UPF entity through the SMF entity during the PDU session establishment procedure of the UE.

To achieve power savings, the UE may negotiate eDRX parameters with the AMF entity, e.g., the UE may negotiate eDRX parameters with the AMF entity during Registration.

Specifically, referring to fig. 3, S301, the UE sends a Registration Request message to the AMF entity to Request eDRX parameters, such as an eDRX cycle and the like. The AMF entity determines the received eDRX parameters including an eDRX period, a PTW length and the like according to the operator strategy, subscription information and the like, and sends the received eDRX parameters to the RAN and the UE through Registration Accept messages. In a possible embodiment, the AMF entity may also send RRC inactivity assistance Information (RRC inactivity Information) to the RAN.

S302, the UE sends a PDU session establishment request message to the AMF entity to request the establishment of the PDU session.

S303, if the eDRX mechanism is enabled by the UE and the AMF entity provides RRC Inactive assistance information to the RAN, the AMF entity sends an N11 request message to the SMF entity, where the N11 request message indicates that the eDRX mechanism is enabled by the UE, and is used to request the UPF entity to query the AMF entity about the reachability state of the UE when a user plane tunnel, e.g., N3tunnel, exists. The SMF entity returns a response message to the AMF entity.

S304, if the SMF entity receives the N11 request message sent by the AMF entity to indicate that the UE enables the eDRX mechanism, the SMF entity indicates the UE enables the eDRX mechanism to the UPF entity. In a possible implementation, a service-based interface message, e.g., an N4Session Estbl Request message, may be used between the SMF entity and the UPF entity to indicate to the UPF entity that the eDRX mechanism is enabled by the UE. The UPF entity returns a response message to the SMF entity.

The second mode is as follows: the AMF entity may forward the first indication message to the UPF entity through the SMF entity during a UE registration procedure.

The second way is similar to the first way, please refer to fig. 4, S401, the UE sends a registration request message to the AMF entity to request eDRX parameters, such as an eDRX cycle, etc.

S402, the AMF entity determines the received eDRX parameters including an eDRX period, a PTW length and the like according to the operator strategy, subscription information and the like, and sends the received eDRX parameters to the RAN and the UE through Registration Accept information. In a possible embodiment, the AMF entity may also send RRC inactivity assistance Information (RRC inactivity Information) to the RAN.

S403, if the eDRX mechanism is enabled by the UE and the AMF entity provides RRC Inactive assistance information to the RAN, the AMF entity sends an N11 request message to the SMF entity, where the N11 request message indicates that the eDRX mechanism is enabled by the UE, and is used to request the UPF entity to query the AMF entity about the reachability state of the UE when a user plane tunnel, e.g., N3tunnel, exists. Alternatively, when the UE and the AMF entity turn off the eDRX mechanism, the AMF entity indicates to the SMF entity that the UE has turned off the eDRX mechanism. The SMF entity returns a response message to the AMF entity.

S404, if the SMF entity receives the N11 request message sent by the AMF entity, the SMF entity indicates to the UPF entity whether the UE enables the eDRX mechanism. In a possible implementation, a service-based interface message may be used between the SMF entity and the UPF entity to indicate to the UPF entity that the eDRX mechanism is enabled for the UE. The UPF entity returns a response message to the SMF entity.

The AMF entity provides eDRX parameters to the RAN if the UE enables the eDRX mechanism, and may also provide eDRX parameters to the UE.

S202, when the UPF entity receives the downlink data, a first request message is sent to the AMF entity, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state.

The UPF entity receives the first indication message from the AMF entity, and determines that the received downlink data may be cached, so that when the UPF entity receives the downlink data, the UPF entity may send a first request message to the AMF entity to request the AMF entity to query whether the UE is in an reachable state, so as to determine whether to cache the downlink data.

Specifically, referring to fig. 5, in S501, the application server AS sends downlink data to the UPF entity.

S502, the UPF entity may send a first request message to the SMF entity after receiving the downlink data, where the first request message is used to request to query whether the terminal device is in a reachable state. In a possible implementation manner, the first request message may be an N4 request message, for example, a Data Notification, where the message carries indication information for requesting the UE reachability state.

S503, the SMF entity sends the received first request message to the AMF entity. In a possible implementation manner, the SMF entity sends an N11 request message to the AMF entity, where the message carries indication information requesting the reachability state of the UE. The AMF entity determines whether the UE is reachable according to the eDRX parameter so as to indicate whether the UE is reachable to the PUF entity.

In the embodiment of the invention, when the UE is in an RRC Inactive state and an eDRX mechanism is started, the AMF entity informs the UPF entity that the UE starts the eDRX mechanism. Therefore, after the UPF entity receives the downlink data, it queries whether the UE is reachable from the AMF entity to determine whether to buffer the received downlink data. Instead of requesting the RAN whether the UE is reachable after receiving downlink data each time, fewer signaling is used, and the network signaling load is reduced.

S203, the UPF entity receives the second indication message from the AMF entity, and caches the downlink data when the terminal equipment is determined to be in the unreachable state based on the second indication message.

The AMF entity determines whether the UE is reachable, i.e. whether the UE is in the PTW, according to the eDRX parameter, and if the UE is in the PTW, the AMF entity may indicate to the SMF entity that the UE is in a reachable state. If the UE is not reachable, the AMF indicates downlink data caching information to the SMF, such as a request for caching the downlink data and the next reachable time of the UE.

Specifically, S504, the AMF entity sends a response message of the first request message to the SMF entity to indicate whether the UE is reachable.

And S505, the SMF entity receives the second indication message of the AMF entity and sends the second indication message to the UPF entity. Wherein, the second indication message may carry the downlink data caching information.

S506, if the second indication message carries the downlink data caching information, it may indicate that the UE is in an unreachable state, and at this time, the UPF entity may cache the received downlink data according to the caching information.

Of course, if the second indication message indicates that the UE is in the reachable state, the UPF entity may send downlink data to the RAN according to the next time the UE is reachable. RAN sends a paging message to UE, UE responds to the paging message to initiate a resume process to establish RRC connection Dedicated Radio Bearer (DRB), connection is established, and RAN sends downlink data to UE.

In summary, in the embodiment of the present invention, when the UE is in the RRC Inactive state and the eDRX mechanism is enabled, the AMF entity notifies the UPF entity that the eDRX mechanism is enabled. Therefore, after the UPF entity receives the downlink data, it queries whether the UE is reachable from the AMF entity to determine whether to buffer the received downlink data. Instead of requesting the RAN whether the UE is reachable after receiving downlink data each time, fewer signaling is used, and the network signaling load is reduced.

The device provided by the embodiment of the invention is described in the following with the attached drawings of the specification.

Referring to fig. 6, based on the same inventive concept, an embodiment of the present invention provides a UPF entity, where the UPF entity includes: memory 601, processor 602, and transceiver 603. The memory 601 and the transceiver 603 may be connected to the processor 602 through a bus interface (fig. 6 is taken as an example), or may be connected to the processor 602 through a dedicated connection line.

The memory 601 may be used to store programs, among other things. A transceiver 603 for transceiving data under the control of the processor 602. The processor 602 may be configured to read the program in the memory 601 and execute the following processes: receiving a first indication message of an AMF entity, wherein the first indication message is used for indicating that the terminal equipment uses an extended discontinuous reception (eDRX) mechanism; when receiving downlink data, sending a first request message to an AMF entity, wherein the first request message is used for requesting the AMF entity to inquire whether terminal equipment is in a reachable state; and receiving a second indication message from the AMF entity, and caching the downlink data when the terminal equipment is determined to be in the unreachable state based on the second indication message.

Optionally, the processor 602 is specifically configured to:

the first indication message forwarded by the AMF entity through the session management function, SMF, entity is received through the transceiver 603.

Optionally, the processor 602 is specifically configured to:

receiving a first indication message forwarded by the SMF from the AMF entity in the terminal device registration process through the transceiver 603;

or the like, or, alternatively,

a first indication message forwarded by the SMF entity during establishment of a protocol data unit, PDU, session by the terminal device is received by the transceiver 603 from the AMF entity.

Optionally, the processor 602 is specifically configured to:

and when the downlink data is received, sending a first request message to the SMF entity through the transceiver so as to send the first request message to the AMF entity through the SMF entity.

Optionally, the processor 602 is further configured to:

upon determining that the received second indication message from the AMF entity indicates that the terminal device is in the reachable state, the received downlink data is sent to the radio access network RAN via the transceiver 603.

Optionally, the second indication message carries downlink data caching information, and the processor is specifically configured to:

Wherein in fig. 6 the bus architecture may comprise any number of interconnected buses and bridges, with one or more processors, represented in particular by processor 602, and various circuits of memory, represented by memory 601, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 603 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 602 is responsible for managing the bus architecture and general processing, and the memory 601 may store data used by the processor 602 in performing operations.

Alternatively, the Memory 601 may include a Read Only Memory (ROM), a Random Access Memory (RAM), and a disk Memory. The memory 601 is used for storing data required by the processor 606 during operation, that is, storing instructions executable by the at least one processor 602, and the at least one processor 602 executes the downlink data caching method provided by the embodiments shown in fig. 2 to fig. 5 by executing the instructions stored in the memory 601. The number of the memory 601 is one or more. The memory 601 is also shown in fig. 6, but it should be noted that the memory 601 is not an optional functional module and is therefore shown in fig. 6 by a dotted line.

Referring to fig. 7, based on the same inventive concept, an embodiment of the present invention provides a UPF entity, which includes a receiving unit 701, a sending unit 702, and a buffering unit 703.

The receiving unit 701 is configured to receive a first indication message from the AMF entity, where the first indication message is used to indicate that the extended discontinuous reception eDRX mechanism is used by the terminal device. The sending unit 702 is configured to send a first request message to the AMF entity when receiving the downlink data, where the first request message is used to request the AMF entity to query whether the terminal device is in a reachable state. The buffer unit 703 is configured to receive the second indication message from the AMF entity, and buffer the downlink data when it is determined that the terminal device is in the unreachable state based on the second indication message.

Optionally, the receiving unit 701 is specifically configured to:

and receiving a first indication message forwarded by the AMF entity through a Session Management Function (SMF) entity.

Optionally, the receiving unit 701 is specifically configured to:

receiving a first indication message forwarded by an SMF (simple message forwarding) in the registration process of terminal equipment from an AMF entity;

or the like, or, alternatively,

and receiving a first indication message forwarded by the SMF entity from the AMF entity in the process of establishing the Protocol Data Unit (PDU) session by the terminal equipment.

Optionally, the sending unit 702 is specifically configured to:

and when the downlink data is received, sending a first request message to a Session Management Function (SMF) entity so as to send the first request message to the AMF entity through the SMF entity.

Optionally, the sending unit 702 is further configured to:

and when the received second indication message from the AMF entity indicates that the terminal equipment is in the reachable state, sending the received downlink data to the Radio Access Network (RAN).

Optionally, the second indication message carries downlink data caching information, and the caching unit 703 is specifically configured to:

The physical devices corresponding to the receiving unit 701, the sending unit 702, and the buffering unit 703 may be the processor 602 or the transceiver 603. The UPF entity may be configured to perform the downlink data buffering method provided by the embodiments shown in fig. 2 to fig. 5. Therefore, regarding the functions that can be realized by each functional module in the device, reference may be made to the corresponding descriptions in the embodiments shown in fig. 2 to fig. 5, which are not repeated.

Referring to fig. 8, based on the same inventive concept, an embodiment of the present invention provides an AMF entity, including: a memory 801, a processor 802, and a transceiver 803. The memory 801 and the transceiver 803 may be connected to the processor 802 through a bus interface (fig. 8 is taken as an example), or may be connected to the processor 802 through a dedicated connection line.

The memory 801 may be used to store programs, among other things. A transceiver 803 for transceiving data under the control of the processor 802. The processor 802 may be configured to read a program in the memory 801 to perform the following processes: sending a first indication message to a UPF entity, wherein the first indication message is used for indicating that the terminal equipment uses an extended discontinuous reception (eDRX) mechanism; receiving a first request message from a UPF entity, wherein the first request message is used for requesting the AMF entity to inquire whether the terminal equipment is in a reachable state; and sending a second indication message to the UPF entity, wherein the second indication message is used for indicating the state of the terminal equipment, so that the UPF entity caches the received downlink data according to the second indication message.

Optionally, the processor 802 is specifically configured to:

a first indication message sent to the SMF entity through the transceiver 803 to send the first indication message to the UPF entity through the SMF entity.

Optionally, the processor 802 is specifically configured to:

in the registration process of the terminal device, a first indication message is sent to the SMF entity through the transceiver 803;

or the like, or, alternatively,

during the establishment of a protocol data unit, PDU, session by the terminal device, a first indication message is sent to the SMF via the transceiver 803.

Optionally, the processor 802 is further configured to:

receiving a second request message from the terminal device through the transceiver 803, wherein the second request message is used for requesting the eDRX parameters from the AMF entity;

the determined eDRX parameters are transmitted to the terminal device through the transceiver 803.

Optionally, the second indication message carries buffering information of the downlink data, so that the UPF entity buffers the downlink data according to the buffering information.

Where in fig. 8 the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 802 and various circuits of memory represented by memory 801 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 803 may be a plurality of elements, i.e., including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 802 is responsible for managing the bus architecture and general processing, and the memory 801 may store data used by the processor 802 in performing operations.

Alternatively, the Memory 801 may include a Read Only Memory (ROM), a Random Access Memory (RAM), and a disk Memory. The memory 801 is used for storing data required by the processors 802 during operation, that is, instructions executable by at least one of the processors 802 are stored, and the at least one of the processors 802 executes the instructions stored in the memory 801 to perform the downlink data buffering method provided in the embodiments shown in fig. 2 to 5. The number of the memories 801 is one or more. The memory 801 is also shown in fig. 8, but it should be noted that the memory 801 is not an optional functional block, and is therefore shown in fig. 8 by a dotted line.

Referring to fig. 9, based on the same inventive concept, an embodiment of the present invention provides an AMF entity, which includes a first sending unit 901, a receiving unit 902, and a second sending unit 903.

The first sending unit 901 is configured to send a first indication message to the UPF entity, where the first indication message is used to indicate that the extended discontinuous reception eDRX mechanism is used by the terminal device. The receiving unit 902 is configured to receive a first request message from the UPF entity, where the first request message is used to request the AMF entity to query whether the terminal device is in a reachable state. The second sending unit 903 is configured to send a second indication message to the UPF entity, where the second indication message is used to indicate a state of the terminal device, so that the UPF entity caches the received downlink data according to the second indication message.

Optionally, the first sending unit 901 is specifically configured to:

and the first indication message is sent to the SMF entity, so that the first indication message is sent to the UPF entity through the SMF entity.

Optionally, the first sending unit 901 is specifically configured to:

in the registration process of the terminal equipment, sending a first indication message to an SMF entity;

or the like, or, alternatively,

and in the process of establishing a Protocol Data Unit (PDU) session by the terminal equipment, sending a first indication message to the SMF.

Optionally, the receiving unit 902 is further configured to:

receiving a second request message from the terminal equipment, wherein the second request message is used for requesting the eDRX parameter to the AMF entity;

the second sending unit 903 is configured to send the determined eDRX parameter to the terminal device.

The physical devices corresponding to the first sending unit 901, the receiving unit 902, and the second sending unit 903 may be the processor 802 or the transceiver 803. The AMF entity may be configured to perform the downlink data buffering method provided in the embodiments shown in fig. 2 to 5. Therefore, regarding the functions that can be realized by each functional module in the device, reference may be made to the corresponding descriptions in the embodiments shown in fig. 2 to fig. 5, which are not repeated.

Based on the same inventive concept, embodiments of the present invention further provide a computer storage medium, where the computer storage medium stores computer instructions, and when the computer instructions run on a computer, the downlink data caching method provided in the embodiments shown in fig. 2 to fig. 5 is executed.

The downlink data caching method, the UPF entity, the AMF entity and the computer storage medium provided by the embodiment of the invention can be applied to a wireless communication system, such as a 5G system. However, suitable communication systems include, but are not limited to, a 5G system or an Evolved system thereof, other Orthogonal Frequency Division Multiplexing (OFDM) based systems, DFT-S-OFDM (DFT-Spread OFDM), Evolved long term Evolution (lte) based systems, new network equipment systems, and the like. In practical applications, the connection between the above devices may be a wireless connection or a wired connection.

It should be noted that the communication system may include a plurality of terminal devices, and the network device may communicate (transmit signaling or transmit data) with the plurality of terminal devices. The terminal device according to the embodiments of the present invention may be a device providing voice and/or data connectivity to a user, a handheld device having a wireless connection function, or another processing device connected to a wireless modem. A wireless user equipment may communicate with one or more core networks via a Radio Access Network (RAN).

It is to be understood that the terms first, second, and the like in the description of the embodiments of the invention are used for distinguishing between the descriptions and not necessarily for describing a sequential or chronological order. "plurality" in the description of the embodiments of the present invention means two or more.

In some possible embodiments, various aspects of the downlink data caching method, the UPF entity and the AMF entity provided by the present invention may also be implemented in the form of a program product, which includes program code for causing a computer device to perform the steps in the downlink data caching method according to various exemplary embodiments of the present invention described above in this specification when the program product runs on the computer device, for example, the computer device may perform the downlink data caching method provided by the embodiments shown in fig. 2 to fig. 5.

The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

The program product for the downstream data caching method of embodiments of the present invention may employ a portable compact disk read only memory (CD-ROM) and include program code, and may be run on a computing device. However, the program product of the present invention is not limited in this regard and, in the present document, a readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

A readable signal medium may include a propagated data signal with readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. A readable signal medium may also be any readable medium that is not a readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

Program code embodied on a readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

It will be clear to those skilled in the art that, for convenience and simplicity of description, the foregoing division of the functional modules is merely used as an example, and in practical applications, the above function distribution may be performed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to perform all or part of the above described functions. For the specific working processes of the system, the apparatus and the unit described above, reference may be made to the corresponding processes in the foregoing method embodiments, and details are not described here again.

In the embodiments provided in the present invention, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implemented, for example, a plurality of units or components may be combined or may be integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a Universal Serial Bus flash disk (usb flash disk), a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, and an optical disk.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A downlink data caching method is characterized by comprising the following steps:

2. The method according to claim 1, wherein the user plane function, UPF, entity receiving the first indication message from the access and mobility management function, AMF, entity comprises:

3. The method of claim 2, wherein the receiving, by the UPF entity, the first indication message forwarded by the session management function, SMF, entity from the AMF entity comprises:

or the like, or, alternatively,

4. The method of claim 1, wherein the transmitting, by the UPF entity, the first request message to the AMF entity upon receiving the downlink data comprises:

5. The method of claim 1, further comprising:

6. The method of claim 1, wherein the second indication message carries downlink data buffering information, and the UPF entity buffers downlink data when determining that the received second indication message from the AMF entity indicates that the terminal device is in an unreachable state, including:

7. A downlink data caching method is characterized by comprising the following steps:

8. The method according to claim 7, wherein the sending of the first indication message by the access and mobility management function, AMF, entity to the user plane function, UPF, entity comprises:

9. The method of claim 8, wherein the first indication message sent by the AMF entity to a Session Management Function (SMF) entity comprises:

or the like, or, alternatively,

10. The method according to claim 9, further comprising, before the access and mobility management function, AMF, entity sending the first indication message to a user plane function, UPF, entity:

11. The method according to claim 7, wherein the second indication message carries buffering information of downlink data, so that the UPF entity buffers the downlink data according to the buffering information.

12. A user plane function, UPF, entity, comprising:

a memory to store instructions;

a transceiver for transceiving data under control of the processor.

13. The UPF entity of claim 12, wherein the processor is specifically configured to:

14. The UPF entity of claim 13, wherein the processor is specifically configured to:

or the like, or, alternatively,

15. The UPF entity of claim 12, wherein the processor is specifically configured to:

16. The UPF entity of claim 12, wherein the processor is further configured to:

17. The UPF entity of claim 12, wherein the second indication message carries downlink data caching information, and wherein the caching unit is specifically configured to:

18. An access and mobility management function, AMF, entity, comprising:

a memory to store instructions;

a transceiver for transceiving data under control of the processor.

19. The AMF entity of claim 18, wherein the processor is specifically configured to:

20. The AMF entity of claim 19, wherein the processor is specifically configured to:

or the like, or, alternatively,

21. The AMF entity of claim 20, wherein the processor is further configured to:

22. The AMF entity of claim 18, wherein the second indication message carries buffering information of downlink data, such that the UPF entity buffers the downlink data according to the buffering information.

23. A user plane function, UPF, entity, comprising:

24. An access and mobility management function, AMF, entity, comprising:

25. A computer storage medium on which a computer program is stored, which computer program, when being executed by a processor, carries out the method according to any one of claims 1-6 or 7-11.