阅读说明：本技术 用于在通信系统中同步QoS流的状态的方法、装置 (Method, apparatus for synchronizing states of QoS flows in a communication system ) 是由 干菊英 陈骞 P·赫德曼 M·瓦斯 S·罗默 于 2019-06-28 设计创作，主要内容包括：本公开涉及一种用于在通信系统中同步QoS流的状态的方法、装置。一种在终端设备处执行的方法,用于在通信系统中同步服务质量(QoS)流的状态。该方法包括：在本地删除(S101)QoS流；将QoS流的状态标记为(S102)被删除且未同步；发送(S103)协议数据单元(PDU)会话修改请求以同步QoS流的状态。根据本公开的实施例,在某些场景下,当QoS流的状态被终端设备或网络侧之一改变时,QoS流的状态仍然可被同步。(The present disclosure relates to a method, apparatus for synchronizing states of QoS flows in a communication system. A method, performed at a terminal device, for synchronizing states of quality of service (QoS) flows in a communication system. The method comprises the following steps: locally deleting (S101) a QoS flow; marking (S102) the status of the QoS flows as deleted and unsynchronized; a Protocol Data Unit (PDU) session modification request is sent (S103) to synchronize the state of the QoS flows. According to embodiments of the present disclosure, in certain scenarios, when the state of a QoS flow is changed by one of the terminal device or the network side, the state of the QoS flow may still be synchronized.)

1. A method performed at a terminal device for synchronizing states of quality of service, QoS, flows in a communication system, the method comprising:

locally deleting (S101) the QoS flow;

marking (S102) the status of the QoS flows as deleted and unsynchronized; and

sending (S103) a protocol data unit, PDU, session modification request to synchronize the state of the QoS flows.

2. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

wherein the QoS flow is deleted due to deletion of a dedicated Evolved Packet System (EPS) bearer;

wherein the QoS flow is mapped from the dedicated EPS bearer in preparation for an interworking procedure of the terminal device from EPS to fifth generation system 5 GS; and

wherein the PDU session modification request comprises: clearing the request for the QoS flow.

3. The method of claim 2, wherein the PDU session modification request is transmitted when the terminal device changes from a CM-IDLE state to a CM-CONNECTED state, wherein CM refers to connection management.

4. The method of any one of claims 1 to 3,

wherein the QoS flow is a QoS flow that is not associated with a default QoS rule.

5. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

wherein the QoS flow is deleted when the terminal device is in 5 GS; and

wherein the PDU session modification request comprises: clearing the request for the QoS flow.

6. The method of claim 5, wherein the first and second light sources are selected from the group consisting of,

wherein the QoS flow is a QoS flow that is not associated with a default QoS rule.

7. A method performed at a network node for synchronizing status of bearers in a communication system, the method comprising:

acquiring (S201) a state of an EPS bearer based on the EPS bearer identity EBI list;

sending (S202) the status of the EPS bearer to a terminal device.

8. The method of claim 7, wherein the first and second light sources are selected from the group consisting of,

wherein the EPS bearer comprises: a default EPS bearer or a dedicated EPS bearer;

wherein the state of the EPS bearer is sent in a registration accept message during an interworking procedure of the terminal device from EPS to 5 GS.

9. The method of claim 7 or 8, further comprising:

the list of EBIs is obtained from one or more system management functions, SMFs.

10. The method of claim 9, wherein the first and second light sources are selected from the group consisting of,

wherein the state of the EPS bearer relates to whether active or inactive.

11. The method according to any one of claims 7 to 10,

wherein the deletion of the EPS bearer is initiated by a mobility management entity MME or a packet data network gateway PGW and is not synchronized with the terminal device.

12. The method according to any one of claims 7 to 11,

wherein the network node is an access and mobility management function, AMF.

13. A method performed at a terminal device for synchronizing status of bearers in a communication system, the method comprising:

receiving (S301) a registration acceptance message during an interworking procedure of the terminal device from EPS to 5 GS;

acquiring (S302) a state of an EPS bearer based on the registration acceptance message;

wherein the state of the EPS bearer is included in the registration accept message by a network node based on an EPS Bearer Identification (EBI) list.

14. The method of claim 13, wherein the first and second light sources are selected from the group consisting of,

wherein the state of the EPS bearer relates to whether active or inactive.

15. A terminal device (100) comprising:

a processor (101); and

a memory (102) containing instructions executable by the processor (101);

wherein the terminal device (100) is operable to:

deleting the QoS flow locally;

marking a status of the QoS flow as deleted and unsynchronized; and

sending a protocol data unit, PDU, session modification request to synchronize the state of the QoS flows.

16. Terminal device (100) according to claim 15,

wherein the terminal device (100) is operable in the method according to any one of claims 2 to 6.

17. A network node (200), comprising:

a processor (201); and

a memory (202) containing instructions executable by the processor (201);

wherein the network node (200) is operable to:

acquiring the state of the EPS bearer based on the EPS bearer identifier EBI list;

and sending the state of the EPS bearer to a terminal device.

18. The network node (200) of claim 17,

wherein the network node (200) is operable in the method according to any of claims 8 to 12.

19. A terminal device (100) comprising:

a processor (101); and

a memory (102) containing instructions executable by the processor (101);

wherein the terminal device (100) is operable to:

receiving a registration acceptance message during an interworking procedure of the terminal device from EPS to 5 GS;

acquiring the state of the EPS bearer based on the registration acceptance message;

wherein the state of the EPS bearer is included in the registration accept message by a network node based on an EPS Bearer Identification (EBI) list.

20. Terminal device (100) according to claim 19,

wherein the terminal device (100) is operable in the method according to claim 14.

21. A computer-readable storage medium (600) having a computer program (601) stored thereon, wherein the computer program (601) is executable by an apparatus to cause the apparatus to perform the method according to any one of claims 1-14.

Technical Field

The present disclosure relates generally to communication technologies, and more particularly, to a method and apparatus for synchronizing states of QoS flows (QoS flows) in a communication system.

Background

This section introduces aspects that help to better understand the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be construed as admissions of prior art or what is not included in the prior art.

In a fifth generation system (5GS), a mechanism for quality of service (QoS) flows is established for providing a method of management of QoS levels (e.g. bit rates) of communications between terminal devices and the network side.

When using QoS flow for communication, both the terminal device and the network side store the state of the QoS flow. The state of the QoS flows should be synchronized, i.e. when either the terminal device or the network side changes the state of the QoS flows, the other should be informed. For example, the 3 rd generation partnership project technical specification 3GPP TS,23.502v15.5.0 has specified that "the SMF may decide to modify a PDU session.. if.. the state that the SMF has marked one or more QoS flows is deleted in the 5GC but it may also be triggered without synchronizing … … with the UE. SMF refers to system management functions. A PDU refers to a protocol data unit. 5GC refers to generation 5 cores. UE refers to user equipment.

However, with the development of communication systems, there are some scenarios in which the state of a QoS flow may be changed by one of the terminal device or the network side and cannot yet be synchronized.

Disclosure of Invention

Certain aspects of the present disclosure and embodiments thereof may provide solutions to at least some of these or other challenges. Various embodiments are presented herein that address one or more of the problems disclosed herein.

A first aspect of the present disclosure provides a method performed at a terminal device for synchronizing states of quality of service (QoS) flows in a communication system. The method comprises the following steps: locally deleting the QoS flow; marking a status of the QoS flow as deleted and unsynchronized; and sending a Protocol Data Unit (PDU) session modification request to synchronize the state of the QoS flows.

In an embodiment of the present disclosure, the QoS flow is deleted due to deletion of a dedicated Evolved Packet System (EPS) bearer. The QoS flows are mapped from the dedicated EPS bearers when preparing an interworking procedure for the terminal device from EPS to a fifth generation system (5 GS). The PDU session modification request includes: clearing (clear up) the request for the QoS flow.

In an embodiment of the present disclosure, the PDU session modification request is transmitted when the terminal device changes from a CM-IDLE (CM-IDLE) state to a CM-CONNECTED (CM-CONNECTED) state, where CM refers to connection management.

In an embodiment of the present disclosure, the QoS flow is a QoS flow that is not associated with a default QoS rule.

In an embodiment of the present disclosure, the QoS flow is deleted when the terminal device is in 5 GS. The PDU session modification request includes: clearing the request for the QoS flow.

In an embodiment of the present disclosure, the QoS flow is a QoS flow that is not associated with a default QoS rule.

A second aspect of the present disclosure provides a method performed at a network node for synchronizing a status of bearers in a communication system, the method comprising obtaining a status of an EPS bearer based on an EPS Bearer Identity (EBI) list; and sending the state of the EPS bearer to a terminal device.

In an embodiment of the present disclosure, the EPS bearer includes: a default EPS bearer or a dedicated EPS bearer. And sending the state of the EPS bearer in a registration acceptance message in the interworking process from the EPS to the 5GS by the terminal equipment.

In an embodiment of the present disclosure, the method further comprises: the list of EBIs is obtained from one or more System Management Functions (SMFs).

In an embodiment of the present disclosure, the state of the EPS bearer relates to being in an active or inactive state.

In an embodiment of the present disclosure, the deletion of the EPS bearer is initiated by a Mobility Management Entity (MME) or a packet data network gateway (PGW) and is not synchronized with the terminal device.

In an embodiment of the present disclosure, the network node is an access and mobility management function (AMF).

A third aspect of the present disclosure provides a method performed at a terminal device for synchronizing bearer states in a communication system, the method comprising: receiving a registration acceptance message during an interworking procedure of the terminal device from EPS to 5 GS; and acquiring the state of the EPS bearing based on the registration acceptance message. The state of the EPS bearer is included in the registration accept message by a network node based on an EPS Bearer Identification (EBI) list.

In an embodiment of the present disclosure, the state of the EPS bearer relates to being in an active or inactive state.

A fourth aspect of the present disclosure provides a terminal device, including: a processor; and a memory including instructions executable by the processor. The terminal device is operable to: locally deleting a quality of service (QoS) flow; marking a status of the QoS flow as deleted and unsynchronized; and sending a Protocol Data Unit (PDU) session modification request to synchronize the state of the QoS flows.

In an embodiment of the present disclosure, the terminal device is operable in any of the above-mentioned methods.

A fifth aspect of the present disclosure provides a network node, comprising: a processor; and a memory containing instructions executable by the processor. The network node is operable to: acquiring the state of the EPS bearer based on an EPS Bearer Identification (EBI) list; and sending the state of the EPS bearer to the terminal equipment.

In an embodiment of the disclosure, the network node is operable with any of the methods described above.

A sixth aspect of the present disclosure provides a terminal device, including: a processor; and a memory containing instructions executable by the processor. The terminal device is operable to: receiving a registration acceptance message during an interworking procedure of the terminal device from EPS to 5 GS; and acquiring the state of the EPS bearing based on the registration acceptance message. The state of the EPS bearer is included in the registration accept message by a network node based on an EPS Bearer Identification (EBI) list.

In an embodiment of the present disclosure, the terminal device is operable in any of the above-mentioned methods.

A seventh aspect of the disclosure provides a computer readable storage medium having a computer program stored thereon, wherein the computer program is executable by an apparatus to cause the apparatus to perform any of the methods described above.

According to embodiments of the present disclosure, in certain scenarios, when the state of a QoS flow is changed by one of the terminal device or the network side, the state of the QoS flow may still be synchronized.

Drawings

The foregoing and other objects, features and advantages of the disclosure will be apparent from the following more particular descriptions of certain embodiments of the disclosure as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts of embodiments of the disclosure.

FIG. 1 is an exemplary flow chart illustrating a method according to an embodiment of the present disclosure;

FIG. 2 is an exemplary flow diagram illustrating sub-steps of the method of FIG. 1 according to an embodiment of the present disclosure;

FIG. 3 is an exemplary flow chart illustrating other methods of embodiments of the present disclosure;

FIG. 4 is an exemplary diagram illustrating an implementation of the method illustrated in FIG. 3 in a communication system;

FIG. 5 is a block diagram illustrating an exemplary terminal device according to an embodiment of the present disclosure;

fig. 6 is a block diagram illustrating an example network node according to an embodiment of the present disclosure; and

FIG. 7 is a schematic diagram illustrating a computer-readable storage medium according to some embodiments.

Detailed Description

Some embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. However, other embodiments are included within the scope of the subject matter disclosed herein, and the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example only to convey the scope of the subject matter to those skilled in the art.

In general, all terms used herein are to be interpreted according to their ordinary meaning in the relevant art, unless explicitly given and/or implicitly to a different meaning in the context in which the term is used. All references to a/an/the element, device, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless one step is explicitly described as being after or before another step and/or implicitly one step must be after or before another step. Any feature of any embodiment disclosed herein may be applied to any other embodiment where appropriate. Likewise, any advantage of any embodiment may apply to any other embodiment, and vice versa. Other objects, features and advantages of the appended embodiments will become apparent from the description that follows.

Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single embodiment of the disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Furthermore, the described features, advantages, and characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the present disclosure may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the disclosure.

As used herein, the term "communication network/system" refers to a network/system that conforms to any suitable communication standard, such as New Radio (NR), Long Term Evolution (LTE), LTE-advanced, Wideband Code Division Multiple Access (WCDMA), High Speed Packet Access (HSPA), and the like. Further, communication between the terminal device and the network node in the communication network may be performed according to any suitable generation of communication protocols, including but not limited to first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), 4G, 4.5G, 5G communication protocols and/or any other protocol currently known or to be developed in the future.

The term "network node" or "network-side node" refers to a network device in a communication network, through which a terminal device accesses the network and receives services therefrom. A network node may refer to a Base Station (BS), an Access Point (AP), a multi-cell/Multicast Coordination Entity (MCE), a controller, or any other suitable device in a wireless communication network. The BS may be, for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a next generation NodeB (gdnodeb or gNB), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), a relay, a low power node (such as femto, pico, etc.). The network node may further comprise: AMF, MME, PGW, etc.

Further examples of network nodes include multi-standard radio (MSR) radios such as MSR BSs, network controllers such as Radio Network Controllers (RNCs) or Base Station Controllers (BSCs), Base Transceiver Stations (BTSs), transmission points, transmission nodes, positioning nodes, and so forth. More generally, however, a network node may represent any suitable device (or group of devices) that is capable, configured, arranged and/or operable to enable and/or provide terminal device access to or provide some service to terminal devices that have access to a wireless communication network.

The term "terminal device" refers to any terminal device that can access a communication network and receive services therefrom. By way of example, and not limitation, a terminal device may refer to a User Equipment (UE) or other suitable device. The UE may be, for example, a subscriber station, a portable subscriber station, a Mobile Station (MS), or an Access Terminal (AT). The terminal devices may include, but are not limited to, portable computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback devices, mobile phones, cellular phones, smart phones, tablets, wearable devices, Personal Digital Assistants (PDAs), vehicles, and the like.

As yet another specific example, in an internet of things (IoT) scenario, a terminal device may also be referred to as an IoT device and represents a machine or other device that performs monitoring, sensing, and/or measurements, etc., and transmits the results of such monitoring, sensing, and/or measurements, etc., to another terminal device and/or network device. In this case, the terminal device may be a machine-to-machine (M2M) device, which may be referred to as a Machine Type Communication (MTC) device in the third generation partnership project (3GPP) context.

As one particular example, the terminal device may be a UE implementing the 3GPP narrowband internet of things (NB-IoT) standard. Specific examples of such machines or devices are sensors, metering devices (such as power meters), industrial machinery, or household or personal appliances (e.g. refrigerators, televisions), personal wearable devices (such as watches), etc. In other cases, the terminal device may represent a vehicle or other device (e.g., a medical instrument) capable of monitoring, sensing, and/or reporting its operational status or other functions associated with its operation.

As used herein, the terms "first," "second," and the like refer to different elements. The singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having" and/or "containing" specify the presence of stated features, elements, and/or components, etc., but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof. The term "based on" is to be understood as "based at least in part on". The terms "one embodiment" and "an embodiment" should be understood as "at least one embodiment". The term "another embodiment" should be understood as "at least one other embodiment". Other definitions (explicit and implicit) may be included below.

By way of example, some scenarios and embodiments will be presented. These scenarios are to be described as exemplary scenarios for implementing embodiments of the present disclosure, and are not limiting.

With the development of communication technology, an integrated communication network may comprise different parts/structures/systems, such as Evolved Packet System (EPS), fifth generation system (5 GS).

Due to changes in usage (e.g., physical location or service requirements), the terminal device may move/handover from one system to another. During an exemplary move from EPS to 5GS while maintaining a communication session between the terminal device and the network side, QoS flows may be established in 5GS and mapped from EPS bearers in EPS.

However, during such movement, one of the terminal device and the network side may delete the QoS flow or the EPS bearer corresponding to the QoS flow and not inform the other, and thus out of synchronization of the state of the QoS flow may occur.

As a first specific embodiment, a terminal device (e.g., UE) remains in an IDLE (IDLE) state in an EPS and then moves to 5 GS. The UE may delete the dedicated EPS bearer in the EPS locally and not notify the network side. Thus, after the PDU session between the UE and the network is established in the 5GS, the network has a QoS flow associated with the deleted dedicated EPS bearer. The QoS flows are not synchronized. When the communication between the UE and the network side starts in 5GS, Downlink (DL) packets will be able to be sent from the network side to the UE on unsynchronized QoS flows. Uplink (UL) packets will likely be sent through other synchronous QoS flows, such as the QoS flow associated with the default QoS rule.

In such a scenario, a possible problem is that differentiation of UL packet forwarding processing cannot be achieved (assuming that the UE does not drop DL packets received from the network on the unsynchronized QoS flow), or the UE will simply drop DL packets received on the unsynchronized QoS flow.

FIG. 1 is an exemplary flow chart illustrating a method according to an embodiment of the present disclosure; and fig. 2 is an exemplary flow diagram illustrating sub-steps of the method of fig. 1 according to an embodiment of the disclosure.

As shown in fig. 1, the method is performed at a terminal device 100 for synchronizing the state of quality of service (QoS) flows in a communication system. The method comprises the following steps: s101, deleting the QoS flow locally; s102, marking the state of the QoS flow as deleted and not synchronized; and S103, sending a Protocol Data Unit (PDU) session modification request to synchronize the state of the QoS flow.

According to an embodiment of the present disclosure, if a terminal device (e.g., UE) deletes a QoS flow locally, the UE may send an explicit non-access stratum (NAS) message (e.g., PDU session modification request) to request the network side to delete the QoS flow for synchronization.

It should be understood that the numbers of S101, S102, S103, etc. are only for simplifying the description, and are not used to limit the sequence of the steps in the method. For example, step S102 may be performed before step S101, or may be performed simultaneously.

As shown in fig. 2, step S101 may include: substep S1011, when the terminal device is in the EPS, locally deleting the dedicated EPS bearer; and S1012, moving from EPS to 5 GS. Alternatively, step S101 may include: sub-step S1013, when the terminal device is in 5GS, the QoS flow is deleted locally.

In an embodiment of the present disclosure, in S1011, the QoS flow is deleted due to deletion of an evolved packet system dedicated (EPS) bearer. When preparing an interworking procedure for the terminal device from EPS to a fifth generation system (5GS), QoS flows are mapped from dedicated EPS bearers. Then, in S1012, the terminal apparatus moves from the EPS to 5 GS. The PDU session modification request includes: the request for the QoS flow is cleared.

According to the embodiment of the present disclosure, when the terminal device changes the state of the QoS flow in the scenario of moving from the EPS to 5GS, the state of the QoS flow may still be synchronized.

In an embodiment of the present disclosure, a PDU session modification request is transmitted when a terminal device changes from a CM-IDLE state to a CM-CONNECTED state, where CM refers to connection management.

According to an embodiment of the present disclosure, the synchronization of the state of the QoS flow may be performed when the UE changes its state from CM-IDLE to CM-CONNECTED the next time.

In an embodiment of the present disclosure, a QoS flow is a QoS flow that is not associated with a default QoS rule.

Further, as a second specific embodiment, the terminal device (e.g. UE) stays in 5GS, or is initially connected to 5GS, or is moved from EPS to 5 GS. Then, in S1013, the UE may delete the QoS flow locally, but not notify the network side. Then the network still has QoS flows. This QoS flow is not synchronized. When communication between the UE and the network side starts, Downlink (DL) packets will be able to be sent from the network side to the UE on an unsynchronized QoS flow. Uplink (UL) packets will likely be sent through other synchronous QoS flows, such as the QoS flow associated with the default QoS rule.

In such a scenario, as in the first embodiment, a possible problem is that differentiation of UL packet forwarding processing cannot be achieved (assuming that the UE does not drop DL packets received from the network on the unsynchronized QoS flow), otherwise the UE would simply drop DL packets on the unsynchronized QoS flow.

The method as shown in fig. 1 is still applicable. And, when the terminal device is in 5GS, the QoS flow is deleted. The PDU session modification request includes: the request for the QoS flow is cleared.

In an embodiment of the present disclosure, a QoS flow is a QoS flow that is not associated with a default QoS rule.

Thus, in the above embodiment, if the UE locally deletes a QoS flow in the 5GS that is not associated with the default QoS rule, the UE sends an explicit non-access stratum (NAS) message (such as a PDU session modification request) to request the network side to delete the QoS flow the next time the UE contacts the network (e.g., before sending the UL packet), thereby achieving synchronization.

That is, according to the embodiments of the present disclosure, when the terminal device changes the state of the QoS flow in the scenario in 5GS, the state of the QoS flow can still be synchronized.

As a third specific embodiment, the terminal device (e.g., UE) moves from EPS to 5 GS. The network side deletes the dedicated EPS bearer in the EPS and does not notify the UE. For example, a Mobility Management Entity (MME) or a packet data network gateway (PGW) may initiate the deletion of dedicated EPS bearers.

Thus, after the PDU session between the UE and the network is established in 5GS, the UE still has QoS flows associated with the deleted dedicated EPS bearer. The QoS flows are not synchronized. When communication between the UE and the network side starts in 5GS, DL packets will be transmitted using other synchronized QoS flows (e.g., QoS flows associated with default QoS rules). UL packets may be transmitted using this unsynchronized QoS flow and may be dropped by the NG-RAN because the NG-RAN cannot match it to any known QoS profile. NG-RAN refers to the next generation radio access network.

In such a scenario, a possible problem is that UL packets on the unsynchronized QoS flows may be dropped and the corresponding service may be interrupted.

Fig. 3 is an exemplary flow chart illustrating other methods according to embodiments of the present disclosure.

As shown in fig. 3, a method for synchronizing the status of bearers in a communication system is performed at a network node 200. The method comprises the following steps: s201, acquiring the state of an EPS bearer based on an EPS Bearer Identification (EBI) list; s202, sending the state of the EPS bearing to the terminal equipment.

In an embodiment of the present disclosure, an EPS bearer includes: a default EPS bearer or a dedicated EPS bearer. The state of the EPS bearer is transferred in a registration accept message during the interworking procedure of the terminal device from EPS to 5 GS.

In an embodiment of the disclosure, the method further comprises: the EBI list is obtained from one or more System Management Functions (SMFs).

In embodiments of the present disclosure, the state of an EPS bearer is related to whether active or inactive.

In embodiments of the present disclosure, the deletion of the EPS bearer is initiated by a Mobility Management Entity (MME) or a packet data network gateway (PGW) and is not synchronized with the terminal device.

In an embodiment of the present disclosure, the network node is an access and mobility management function (AMF).

Thus, as shown in fig. 3, a method for synchronizing the status of bearers in a communication system is performed at a terminal device. The method comprises the following steps: s301, receiving a registration acceptance message during the interworking process from the EPS to the 5GS of the terminal equipment; s302, acquiring the state of the EPS bearing based on the registration acceptance message. The state of the EPS bearer is included in the registration accept message by the network node based on an EPS Bearer Identity (EBI) list.

In embodiments of the present disclosure, the state of an EPS bearer is related to whether active or inactive.

According to the above embodiments, if the network side deletes the EPS bearer and does not notify the UE, it is proposed that the AMF includes a new EPS bearer state IE in the registration accept message based on the EBI list currently provided by the SMF, so as to update the state of the QoS flow mapped from the EPS bearer.

That is, according to the embodiment of the present disclosure, in a scenario where the terminal device moves from the EPS to the 5GS, when the network side changes the state of the QoS flow, the state of the QoS flow may still be synchronized.

Fig. 4 is an exemplary diagram illustrating an embodiment of the method illustrated in fig. 3 in a communication system.

As shown in fig. 4, the terminal equipment (UE)100 moves from EPS to 5 GS. During or before this movement, in step 1, the MME 300 or the PGW (e.g. PGW-C + SMF 501 or PGW-C + SMF 502) initiates the deletion of the dedicated EPS bearer, but does not inform the UE. PGW-C + SMF refers to a packet data network gateway-control plane + system management function.

In step 2, the UE 100 sends a registration request to the network node (AMF) 200. In step 3, the AMF 200 obtains a context response (for the UE EPS PDN connection) from the MME 300. In steps 4 and 7, the AMF 200 transmits an "Nsmf _ pduse _ CreateSMContext" request message to the access system management function V-SMF 400 and receives a response. In step 5.1 and step 6.1, V-SMF 400 sends an "Nsmf _ pdussession _ Create" request to PGW-C + SMF 501 and receives a response. Step 5.2 and step 6.2 are the same as step 5.1 and step 6.1 and are used only to illustrate that V-SMF 400 may be linked to more than one PGW-C + SMF. In step 8, the AMF 200 acquires the EPS bearer status using the EBI list provided by the SMF. The AMF 200 then sends a response message, e.g. a registration accept message, including the EPS bearer status in step 9.

The EBI list may include information about EPS bearer identifiers.

In this embodiment, since the EPS bearer in EPS will be mapped to QoS flow in 5GS, the synchronization of EPS bearer state is equivalent to the synchronization of the state of QoS flow.

An EPS bearer status Information Element (IE) may be used to indicate EPS bearer status to indicate whether an EPS bearer is in an active state. A value of "1" indicates active and a value of "0" indicates inactive.

According to the embodiment of the disclosure, in the scenario that the terminal device moves from the EPS to the 5GS, when the network side changes the state of the QoS flow, the state of the QoS flow can still be synchronized.

Fig. 5 is a block diagram illustrating an exemplary terminal device according to an embodiment of the present disclosure.

As shown in fig. 5, the terminal device 100 includes: a processor 101; and a memory 102 containing instructions executable by the processor 101. The terminal device is operable to: locally deleting (S101) a quality of service (QoS) flow; marking (S102) the state of the QoS flow as deleted and not synchronized; and sending (S103) a Protocol Data Unit (PDU) session modification request to synchronize the state of the QoS flows.

In an embodiment of the present disclosure, the terminal device is operable in any one of the above-mentioned methods.

Fig. 6 is a block diagram illustrating an example network node according to an embodiment of the present disclosure.

As shown in fig. 6, the network node 200 includes: a processor 201; and a memory 202 containing instructions executable by the processor 201. The network node 200 is operable to: obtaining (S201) a status of an EPS bearer based on an EPS Bearer Identity (EBI) list; the status of the EPS bearer is sent (S202) to the terminal device.

In an embodiment of the disclosure, the network node is operable with any of the methods described above.

Thus, the terminal device 100 is operable to: receiving (S301) a registration acceptance message during an interworking procedure of the terminal device from EPS to 5 GS; based on the registration acceptance message, a status of the EPS bearer is acquired (S302). The state of the EPS bearer is included in the registration accept message by the network node based on an EPS Bearer Identity (EBI) list.

In an embodiment of the present disclosure, the terminal device is operable in any one of the above-mentioned methods.

The processor 101, 201 may be configured to: executing machine instructions stored in memory 102, 202 as a machine-readable computer program, such as one or more hardware-implemented state machines (e.g., in discrete logic, FPGAs, ASICs, etc.); programmable logic with appropriate firmware; one or more stored programs, a general-purpose processor such as a microprocessor or Digital Signal Processor (DSP), and appropriate software; or any combination of the above.

An embodiment of the present disclosure provides a virtual device for a terminal device, including: a deletion unit configured to locally delete (S101) a quality of service (QoS) flow; a marking unit configured to mark (S102) the status of the QoS flows as deleted and unsynchronized; and a transmitting unit configured to transmit (S103) a Protocol Data Unit (PDU) session modification request to synchronize the state of the QoS flows.

An embodiment of the present disclosure provides a virtual device for a network node, including: an obtaining unit configured to obtain (S201) a status of an EPS bearer based on an EPS Bearer Identity (EBI) list; a transmitting unit configured to transmit (S202) a status of an EPS bearer to a terminal device.

Correspondingly, an embodiment of the present disclosure further provides a virtual device for a terminal device, including: a receiving unit configured to receive (S301) a registration acceptance message during an interworking procedure of the terminal device from EPS to 5 GS; an obtaining unit configured to obtain (S302) a status of an EPS bearer based on the registration acceptance message. The state of the EPS bearer is included in the registration accept message by the network node based on an EPS Bearer Identity (EBI) list.

By virtual means, the access management node and the session management node may not need a fixed processor or memory and any computational and storage resources may be arranged from at least one node device in the network. The introduction of virtualization technology and network computing technology can improve the use efficiency of network resources and the flexibility of the network.

Fig. 7 is a schematic diagram illustrating a computer-readable storage medium 600 according to some embodiments.

As shown in fig. 7, a computer readable storage medium 600 has a computer program 601 stored thereon, wherein the computer program is executable by an apparatus to cause the apparatus to perform any of the methods described above, such as the methods shown in fig. 1, 2, 3, 4.

The computer-readable storage medium 600 may include any form of volatile or non-volatile computer-readable memory, including, but not limited to, permanent memory, solid-state memory, remotely-mounted memory, magnetic media, optical media, random-access memory (RAM), read-only memory (ROM), mass storage media (e.g., a hard disk), removable storage media (e.g., a flash drive, Compact Disc (CD), or Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device-readable and/or computer-executable storage device that stores information, data, and/or instructions that may be used by the processors 101, 201. The computer-readable storage medium 600 may store any suitable instructions, data, or information, including computer programs, software, applications including one or more of logic, rules, code, tables, etc., and/or other instructions capable of being executed by the processors 201, 301. The computer-readable storage medium 600 may be used to store any calculations performed by the processors 101, 201 and/or any data received via an external interface. In some embodiments, the processors 101, 201 and the computer-readable storage medium 900 may be considered integrated.

According to embodiments of the present disclosure, in certain scenarios, when the state of a QoS flow is changed by one of the terminal device or the network side, the state of the QoS flow may still be synchronized.

It should be appreciated that at least some aspects of the exemplary embodiments of this disclosure may be embodied in computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device. The computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, RAM, etc. Those skilled in the art will appreciate that the functionality of the program modules may be combined or distributed as desired in various embodiments. Further, the functionality may be embodied in whole or in part in firmware or hardware equivalents such as integrated circuits, Field Programmable Gate Arrays (FPGAs), etc.

The term unit may have a conventional meaning in the field of electronics, electrical and/or electronic devices and may include, for example, electrical and/or electronic circuits, devices, modules, processors, memories, logical solid-state and/or discrete devices, computer programs or instructions for performing various tasks, procedures, calculations, output and/or display functions, etc., such as those described herein.