CN115915495A

CN115915495A - Method, device and system for session reestablishment

Info

Publication number: CN115915495A
Application number: CN202110996699.1A
Authority: CN
Inventors: 黄亚超; 肖方强; 张卓阳; 丁辉
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-08-27
Filing date: 2021-08-27
Publication date: 2023-04-04
Also published as: WO2023024864A1

Abstract

The application provides a method, a device and a system for session reestablishment, which comprise the following steps: the method comprises the steps that a first network element receives network element information of a second network element from a network storage function network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating an affected session between the first network element and the second network element; and the first network element performs session reestablishment with the second network element according to the session characteristic information. According to the technical scheme of the application, the network storage function network element can send the network element information of the second network element to the first network element, the network element information comprises session characteristic information, and the first network element can determine the affected session between the first network element and the second network element according to the session characteristic information, so that session reconstruction can be performed quickly and accurately.

Description

Method, device and system for reestablishing session

Technical Field

The present application relates to the field of communications, and more particularly, to a method, an apparatus, and a system for session reestablishment.

Background

At present, after a session is established with a session management network element or an access and mobility management network element, a policy control network element may lose session information in a scenario of device failure, network exit, load balancing (a part of signed data is migrated to a device of a message), and the like, and at this time, the policy control network element may send network element update information to the session management network element or the access and mobility management network element, so as to perform session reconstruction with the session management network element or the access and mobility management network element.

However, the sessions lost in the actual failure are usually granular by Data Network Name (DNN) or Network Slice Selection Assistance Information (NSSAI), and only the target DNN or NSSAI user session is affected. In the method, each notification triggers the reconstruction process of the full user session under the policy control network element, the session cannot be rapidly and accurately reconstructed, and meanwhile, the core network generates great signaling waste.

Disclosure of Invention

The application provides a method, a device and a system for session reestablishment, which are beneficial to rapidly and accurately reestablishing the session.

In a first aspect, a method for session reestablishment is provided, including: the method comprises the steps that a first network element receives network element information of a second network element from a network storage function network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating an affected session between the first network element and the second network element; and the first network element performs session reestablishment with the second network element according to the session characteristic information.

Affected sessions include, but are not limited to, lost sessions and sessions in which subsequent messages are abnormal.

According to the technical scheme of the application, the network storage function network element can send the network element information of the second network element to the first network element, the network element information comprises session characteristic information, and the first network element can determine the affected session between the first network element and the second network element according to the session characteristic information, so that session reconstruction can be performed quickly and accurately.

Wherein, the session feature information includes at least one of the following: a data network name DNN, network slice selection assistance information NSSAI, and a public land mobile network identifier (PLMN ID).

With reference to the first aspect, in some implementation manners of the first aspect, the foregoing network element information further includes a first recovery time, and the session reestablishment between the first network element and the second network element according to the session feature information includes: and the first network element performs session reestablishment with the second network element according to the session characteristic information and the first recovery time.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: and the first network element determines that the second network element fails according to the first recovery time and the second recovery time, wherein the second recovery time is locally stored, and the second network element fails, including that the second network element itself fails and/or a link between the second network element and the application function network element fails.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: and the first network element subscribes the network element information of the second network element to the network storage function network element.

With reference to the first aspect, in some implementations of the first aspect, the second network element is a policy control network element, and the first network element is an access and mobility management network element, a session management network element, or a network open network element; or the second network element is a unified data management network element, and the first network element is an access and mobility management network element, a session management network element, a short message service network element or an authentication server network element; or the second network element is a unified data storage network element, and the first network element is a unified data management network element, a policy control network element or a network open network element.

In a second aspect, a method for session reestablishment is provided, where the method includes: the second network element sends network element information to the network storage function network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating an affected session between the second network element and the first network element; and the second network element performs session reestablishment with the first network element according to the session characteristic information.

According to the technical scheme of the application, the network storage function network element can send the network element information of the second network element to the first network element, the network element information comprises session characteristic information, and the first network element can determine the affected session between the first network element and the second network element according to the session characteristic information, so that the session reconstruction can be performed quickly and accurately.

Wherein, the session feature information includes at least one of the following: a data network name DNN, network slice selection assistance information NSSAI and a public land mobile network identity PLMN ID.

With reference to the second aspect, in some implementation manners of the second aspect, the above network element information further includes a first recovery time, and the session reestablishment performed by the second network element with the first network element according to the session feature information includes: and the second network element performs session reestablishment with the first network element according to the session characteristic information and the first recovery time.

With reference to the second aspect, in some implementations of the second aspect, the method further includes: and the second network element determines that the second network element has a fault and/or a link between the second network element and the application function network element has a fault.

With reference to the second aspect, in some implementations of the second aspect, the method further includes: and the second network element registers the network element information of the second network element to the network storage function network element, wherein the network element information comprises second recovery time, and the second recovery time is locally stored.

With reference to the second aspect, in some implementations of the second aspect, the second network element is a policy control network element, and the first network element is an access and mobility management network element, a session management network element, or a network open network element; or,

the second network element is a unified data management network element, and the first network element is an access and mobility management network element, a session management network element, a short message service network element or an authentication server network element; or,

the second network element is a unified data storage network element, and the first network element is a unified data management network element, a policy control network element or a network open network element.

In a third aspect, a session reestablishing apparatus is provided for implementing the above method. The session reestablishing apparatus may be the first network element entity in the first aspect, or an apparatus including the first network element entity. The session reestablishing apparatus includes modules, units, or means (means) corresponding to the above methods, and the modules, units, or means may be implemented by hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions.

With reference to the third aspect, in some possible implementations, the session reestablishment apparatus may include a processing module and a transceiver module. The transceiver module, which may also be referred to as a transceiver unit, is configured to implement the transmitting and/or receiving functions in the first aspect and any possible implementation manner thereof. The transceiver module may be formed by a transceiver circuit, a transceiver or a communication interface. The processing module may be configured to implement the processing function in the first aspect and any possible implementation manner thereof. The processing module may be, for example, a processor.

With reference to the third aspect, in certain implementations of the third aspect, the session reestablishing apparatus includes: a receiving unit, configured to receive network element information of a second network element from a network storage function network element, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between a first network element and the second network element; and the processing unit is used for carrying out session reconstruction with the second network element according to the session characteristic information.

Wherein, the session feature information includes at least one of: a data network name DNN, network slice selection assistance information NSSAI and a public land mobile network identity PLMN ID.

With reference to the third aspect, in some implementations of the third aspect, the network element information further includes a first recovery time, and the processing unit is specifically configured to perform session reestablishment with the second network element according to the session characteristic information and the first recovery time.

With reference to the third aspect, in some implementations of the third aspect, the processing unit is further configured to determine that the second network element fails according to the first recovery time and the second recovery time, where the second recovery time is locally stored, and the second network element failure includes a failure of the second network element itself and/or a failure of a link between the second network element and the application function network element.

With reference to the third aspect, in certain implementation manners of the third aspect, the transceiver unit is further configured to subscribe, to the network element information of the second network element, to the network storage function network element.

With reference to the third aspect, in some implementations of the third aspect, the second network element is a policy control network element, and the first network element is an access and mobility management network element, a session management network element, or a network open network element; or,

With reference to the third aspect, in other possible implementations, the transceiver module includes a sending module and a receiving module, which are respectively configured to implement sending and receiving functions in any one of the above aspects and any possible implementation manner thereof.

In a fourth aspect, a session reestablishing apparatus is provided for implementing the above method. The session reestablishing apparatus may be the second network element entity in the second aspect, or an apparatus including the second network element entity. The session reestablishing apparatus includes modules, units, or means (means) corresponding to the above methods, and the modules, units, or means may be implemented by hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions.

With reference to the fourth aspect, in some possible implementations, the session reestablishment apparatus may include a processing module and a transceiver module. The transceiver module, which may also be referred to as a transceiver unit, is configured to implement the transmitting and/or receiving functions in the second aspect and any possible implementation manner thereof. The transceiver module may be formed by a transceiver circuit, a transceiver or a communication interface. The processing module may be configured to implement the processing function in the second aspect and any possible implementation manner thereof. The processing module may be, for example, a processor.

With reference to the fourth aspect, in some implementations of the fourth aspect, the session reestablishing apparatus includes: the receiving and sending unit is used for sending network element information of a second network element to a network storage function network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating an affected session between the second network element and a first network element; and the processing unit is used for carrying out session reestablishment with the first network element according to the session characteristic information.

Wherein the session feature information includes at least one of: a data network name DNN, network slice selection assistance information NSSAI and a public land mobile network identity PLMN ID.

With reference to the fourth aspect, in some implementations of the fourth aspect, the network element information further includes a first recovery time, and the processing unit is specifically configured to perform session reestablishment with the first network element according to the session characteristic information and the first recovery time.

With reference to the fourth aspect, in some implementations of the fourth aspect, the processing unit is further configured to determine that the second network element itself fails and/or that a link between the second network element and the application function network element fails.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the transceiver unit is further configured to register network element information of the second network element with the network storage function network element, where the network element information includes a second recovery time, and the second recovery time is locally stored.

With reference to the fourth aspect, in some implementations of the fourth aspect, the second network element is a policy control network element, and the first network element is an access and mobility management network element, a session management network element, or a network open network element; or,

In a fifth aspect, an apparatus for reestablishing a session is provided, including: a processor; the processor is configured to be coupled to the memory, and to execute the method according to any one of the above aspects after reading the instruction in the memory. The session reestablishing apparatus may be the first network element entity in the first aspect, or an apparatus including the first network element entity; alternatively, the session reestablishing apparatus may be the second network element entity in the second aspect, or an apparatus including the second network element entity.

With reference to the fifth aspect, in a possible implementation manner, the session reestablishing apparatus further includes a memory, and the memory is used for storing necessary program instructions and data.

With reference to the fifth aspect, in a possible implementation manner, the session reestablishing apparatus is a chip or a chip system. Optionally, when the session reestablishing apparatus is a chip system, the session reestablishing apparatus may be formed by a chip, or may include a chip and other discrete devices.

In a sixth aspect, a session reestablishing apparatus is provided, including: a processor and interface circuitry; an interface circuit for receiving a computer program or instructions and transmitting the same to a processor; the processor is adapted to execute a computer program or instructions to cause the session re-establishment apparatus to perform the method of the first or second aspect as described above.

With reference to the sixth aspect, in a possible implementation manner, the session reestablishing apparatus is a chip or a chip system. Optionally, when the session reestablishing apparatus is a chip system, the session reestablishing apparatus may be formed by a chip, or may include a chip and other discrete devices.

In a seventh aspect, a communication system is provided, which includes the above first network element and second network element.

The second network element is used for sending network element information, the network element information includes session characteristic information, and the session characteristic information is used for indicating the session affected by the second network element and the first network element; the first network element is used for receiving the network element information and carrying out session reconstruction with the second network element according to the session characteristic information.

With reference to the seventh aspect, in a possible implementation manner, the system further includes a network storage function network element,

the network storage function network element is used for receiving network element information from a second network element; and sending network element information to the first network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating the affected session between the second network element and the first network element.

In an eighth aspect, there is provided a computer program product comprising: computer program code which, when run on a computer, causes the computer to perform the method of the above-mentioned aspects.

It should be noted that, all or part of the computer program code may be stored in the first storage medium, where the first storage medium may be packaged together with the processor or may be packaged separately from the processor, and this is not specifically limited in this embodiment of the present application.

In a ninth aspect, a computer-readable medium is provided, which stores program code, which, when run on a computer, causes the computer to perform the method in the above aspects.

A tenth aspect provides a chip system, including a memory for storing a computer program and a processor for calling and running the computer program from the memory, so that a communication device in which the chip system is installed executes the method in any of the first to fourth aspects and possible implementations thereof.

The system-on-chip may include, among other things, an input chip or interface for transmitting information or data, and an output chip or interface for receiving information or data.

Drawings

Fig. 1 is a schematic diagram of a system architecture according to an embodiment of the present application.

Fig. 2 is a schematic diagram of an example of a communication system to which the present application is applied.

Fig. 3 is a schematic diagram illustrating an example of a service architecture of a 5G system to which the present application is applied.

Fig. 4 is a schematic flow chart of an example of the session reestablishment method of the present application.

Fig. 5 is a schematic flowchart of a specific example of the session reestablishment method according to the present application.

Fig. 6 is another exemplary schematic flowchart of a specific example of the session reestablishment method according to the present application.

Fig. 7 is a schematic block diagram of an example of a session reestablishment apparatus according to the present application.

Fig. 8 is a schematic block diagram showing an example of a session reestablishing apparatus according to the present application.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of a communication system provided herein. As shown in fig. 1, the system includes a first network element 110 and a second network element 120. Optionally, the system 100 may further include a network storage function network element 130. The system 100 may be used to perform a session re-establishment method of the embodiments of the present application.

And the second network element 120 is configured to send network element information, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between the second network element 120 and the first network element 110.

The first network element 110 is configured to receive the network element information, and perform session reestablishment with the second network element according to the session feature information.

Optionally, the network storage function network element 130 is configured to receive network element information from the second network element 110; and sending network element information to the first network element, wherein the network element information includes session feature information, and the session feature information is used for indicating an affected session between the second network element 120 and the first network element 110.

Illustratively, according to the communication system provided by the present application, the network storage function network element may send network element information of the second network element to the first network element, where the network element information includes session feature information, and the first network element may determine, according to the session feature information, an affected session between the first network element and the second network element, so as to quickly and accurately perform session reestablishment.

The system 100 shown in fig. 1 may be applied to the fifth generation (5g) network architecture shown in fig. 2 or fig. 3, and may also be applied to a future network architecture, such as a sixth generation (6g) network architecture, and the like, which is not limited in this embodiment.

For example, assuming that the communication system shown in fig. 1 is applied to the 5G network shown in fig. 2 or fig. 3, the second network element may be a Policy Control Function (PCF), and the first network element may be an access and mobility management function (AMF), a Session Management Function (SMF), or a network open function (NEF); or, the second network element may be a unified data management network element (UDM), and the first network element may be an access and mobility management network element AMF, a session management network element SMF, a Short Message Service Function (SMSF), or an authentication server network element (AUSF); alternatively, the second network element may be a unified data storage network element (UDR), and the first network element may be a unified data management network element UDM, a policy control network element PCF, or a network open network element NEF.

The following will illustrate the 5G system in different scenarios with reference to fig. 2 and 3. It should be understood that the 5G system described herein is an example only and should not be construed as limiting the present application in any way.

Fig. 2 shows a basic 5G system 200 architecture. As shown in fig. 2, the system 200 includes: PCF, AMF, session management function SMF, radio Access Network (RAN), unified data management UDM, data Network (DN), user Plane Function (UPF), UE, application Function (AF), and/or unified data storage UDR. Optionally, the following functions (not shown in fig. 2) may also be included in fig. 2: a Network Slice Selection Function (NSSF), an authentication server function AUSF, a network open function NEF, or a network storage function NRF.

The main functions of each network element are described as follows:

1. terminal device

The terminal device in the embodiment of the present application may be: user Equipment (UE), mobile Station (MS), mobile Terminal (MT), access terminal, subscriber unit, subscriber station, mobile station, remote terminal, mobile device, user terminal, wireless communication device, user agent, or user device, etc.

The terminal device may be a device providing voice/data connectivity to a user, e.g. a handheld device, a vehicle mounted device, etc. with wireless connection capability. Currently, some examples of terminals are: mobile phone (mobile phone), tablet computer, notebook computer, palmtop computer, mobile Internet Device (MID), wearable device, virtual Reality (VR) device, augmented Reality (AR) device, wireless terminal in industrial control (industrial control), wireless terminal in unmanned driving (self-automation), wireless terminal in remote surgery (remote medical supply), wireless terminal in smart grid (smart grid), wireless terminal in transportation security (transportation security), wireless terminal in smart city (smart city), wireless terminal in smart home (smart home), cellular phone, cordless phone, session initiation protocol (session initiation protocol), SIP) phone, wireless Local Loop (WLL) station, personal Digital Assistant (PDA), handheld device with wireless communication function, computing device or other processing device connected to wireless modem, vehicle-mounted device, wearable device, terminal device in future 5G network or terminal device in future evolved Public Land Mobile Network (PLMN), etc., which is not limited by the embodiments of the present application.

By way of example and not limitation, in the embodiments of the present application, the terminal device may also be a wearable device. Wearable equipment can also be called wearable intelligent equipment, is the general term of equipment that uses wearable technique to carry out intelligent design, develop can dress to daily wearing, such as glasses, gloves, wrist-watch, dress and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the clothing or accessories of the user. The wearable device is not only a hardware device, but also realizes powerful functions through software support, data interaction and cloud interaction. The generalized wearable smart device includes full functionality, large size, and can implement full or partial functionality without relying on a smart phone, such as: smart watches or smart glasses and the like, and only focus on a certain type of application function, and need to be matched with other equipment such as a smart phone for use, such as various smart bracelets for physical sign monitoring, smart jewelry and the like. In addition, in this embodiment, the terminal device may also be a terminal device in an internet of things (IoT) system.

2. Wireless access network

The wireless access network is an access network for realizing the function of accessing the network based on the wireless communication technology. The wireless access network can manage wireless resources, provide wireless access or air interface access service for the terminal, and further complete the forwarding of control signals and user data between the terminal and the core network.

As an example and not by way of limitation, the radio access network may be an evolved NodeB (eNB or eNodeB) in an LTE system, and may also be a wireless controller in a Cloud Radio Access Network (CRAN) scenario, or the access device may be a relay station, an access point, a vehicle-mounted device, a wearable device, and an access device in a 5G network or an access device in a PLMN network that evolves in the future, and may be an Access Point (AP) in a WLAN, and may be a gNB in an NR system.

3. Access and mobility management function network element

The access and mobility management function network element is mainly used for mobility management, access management, and the like, and may be used to implement functions other than session management in a Mobility Management Entity (MME) function, for example, functions such as lawful interception, or access authorization (or authentication), and is also used to transfer a user policy between the UE and the PCF. In the embodiment of the present application, the method and the device can be used for implementing the functions of the access and mobility management network element.

4. Session management function network element

The session management function network element is mainly used for session management, internet Protocol (IP) address allocation and management of the terminal device, selection of a User Plane Function (UPF) network element, a terminal node of a policy control and charging function interface, downlink data notification, and the like. In the embodiment of the present application, the function of the session management network element may be implemented.

5. User plane function network element

The user plane function network element may be used for packet routing and forwarding, or QoS parameter processing of user plane data, etc. The user data may be accessed to a Data Network (DN) through the network element. In the embodiment of the present application, the method and the device may be used to implement a function of a user plane network element, for example, when sessions are established on different UPFs, service experiences of UEs may also be different, and therefore, the SMF needs to select a suitable UPF for the session of the UE.

6. Policy control network element

The policy control network element is a unified policy framework for guiding network behavior, and provides policy rule information for control plane function network elements (such as AMF, SMF network elements, and the like). The method is mainly responsible for carrying out charging, qoS bandwidth guarantee and mobility management, UE strategy decision and other strategy control functions aiming at the conversation and service flow level. In the embodiment of the present application, PCFs connected to the AMF and the SMF respectively correspond to an AM PCF (PCF for Access and Mobility Control) and an SM PCF (PCF for Session Management), and may be the same PCF entity or two different PCF entities in an actual deployment scenario.

7. Network capability open function network element

The network capability opening function element is configured to open a service and network capability information (such as a terminal location and whether a session is reachable) provided by the 3GPP network function to the outside.

8. Application function network element

The application function network element is mainly used for transferring the requirements of the application side to the network side, such as QoS requirements or user state event subscription. The AF may be a third party functional entity, or may be an application service deployed by an operator, such as an IMS voice call service. For the application function entity of the third party application, when interacting with the core network, the authorization processing can be performed through the NEF, for example, the third party application function directly sends the request message to the NEF, the NEF determines whether the AF is allowed to send the request message, and if the AF passes the verification, the request message is forwarded to the corresponding PCF or the unified data management UDM.

9. Unified data management network element

The unified data management network element is mainly used for unified data management, and supports authentication trust state processing, user identity processing, access authorization, registration and mobility management, subscription management, short message management and the like in a 3GPP authentication and key agreement mechanism.

10. Unified data storage network element

The unified data storage network element is mainly used for the access function of the type data such as subscription data, strategy data, application data and the like.

11. Data network

The data network refers to a specific data service network to which the UE has access, and for example, a typical DN includes internet, IP multimedia subsystem (IPMS).

In the above architecture, the functions of each interface are described as follows:

n7: and the interface between the PCF and the SMF is used for transmitting the PDU session granularity and the service data flow granularity control strategy.

N15: and the interface between the PCF and the AMF is used for issuing the UE strategy and the access control related strategy.

N5: and the interface between the AF and the PCF is used for issuing the application service request and reporting the network event.

N4: the interface between SMF and UPF is used for transmitting information between control plane and user plane, including controlling the down sending of forwarding rule, qoS control rule, flow statistic rule, etc. facing to user plane and the information reporting of user plane.

N11: and the interface between the SMF and the AMF is used for transmitting PDU session tunnel information between the RAN and the UPF, transmitting control information sent to the UE, transmitting radio resource control information sent to the RAN and the like.

N2: and the interface between the AMF and the RAN is used for transmitting radio bearer control information from the core network side to the RAN and the like.

N1: the interface between the AMF and the UE, access independence, is used to deliver QoS control rules to the UE, etc.

N8: and the interface between the AMF and the UDM is used for acquiring the subscription data and the authentication data related to access and mobility management from the UDM by the AMF, registering the current mobility management related information of the UE from the UDM by the AMF and the like.

N10: and the interface between the SMF and the UDM is used for acquiring the subscription data related to the session management from the SMF to the UDM, registering the related information of the current session of the UE from the SMF to the UDM, and the like.

N35: and the interface between the UDM and the UDR is used for acquiring the user subscription data information from the UDR by the UDM.

N36: and the interface between the PCF and the UDR is used for the PCF to acquire the subscription data related to the strategy and the application data related information from the UDR.

N52: an interface between the UDM and the NEF is used for the NEF to open network capabilities to third party application functions, such as the third party application functions subscribing to the UDM for reachability events of all users in a particular group through the NEF.

In addition, the NEF also has direct interfaces with both the AMF and the SMF, which respectively correspond to an N29 interface and an N51 interface (not shown in the figure for simplicity), and is used to open the network capability of the operator to a third-party Application function entity, where the former may be used by the NEF to directly subscribe to the AMF for a corresponding network event and update user configuration information, and the latter may be used to update Application configuration data on the SMF/UPF, such as Packet Flow Description (PFD) corresponding to an Application ID.

It should be understood that the network architecture applied to the embodiments of the present application is only an example of a network architecture described from the perspective of a conventional point-to-point architecture and a service architecture, and the network architecture to which the embodiments of the present application are applied is not limited thereto, and any network architecture capable of implementing the functions of the above network elements is applicable to the embodiments of the present application.

It should be understood that the name of the interface between each network element in fig. 2 is only an example, and the name of the interface in the specific implementation may be other names, which is not specifically limited in this application. In addition, the name of the transmitted message (or signaling) between the network elements is only an example, and the function of the message itself is not limited in any way.

It should be noted that the above network elements may also be referred to as entities, devices, apparatuses, or modules, and the present application is not particularly limited. In the present application, for convenience of understanding and explanation, a description of a network element is omitted in a part of the description, for example, an SMF network element is abbreviated as SMF, in which case the "SMF" is understood as an SMF network element, and an explanation of the same or similar cases is omitted below.

It is to be understood that the above network elements or functions may be network elements in a hardware device, or may be software functions running on dedicated hardware, or virtualization functions instantiated on a platform (e.g., a cloud platform). Optionally, the network element or the function may be implemented by one device, may also be implemented by multiple devices together, and may also be a functional module in one device, which is not specifically limited in this embodiment of the present application.

It should also be understood that in the communication system shown in fig. 2, the functions of the respective constituent network elements are merely exemplary, and not all the functions of the respective constituent network elements are necessary when applied to the embodiments of the present application.

Furthermore, the naming of the various network elements (e.g., PCF, AMF, etc.) as included in fig. 2 is merely a name, which does not limit the functionality of the network elements themselves. In a 5G network and other future networks, the above network elements may also be other names, and this embodiment of the present application is not limited in this respect. For example, in a 6G network, some or all of the above network elements may use the terminology in 5G, or may use other nomenclature, and so on, which are described herein in a unified manner and will not be described again below.

It should be further noted that, in fig. 2, communication between network elements of the control plane function is described by taking an unserviceable interface as an example, but the scope of the embodiments of the present application is not limited thereto. Those skilled in the art can understand that each network element of the control plane function in fig. 2 may also communicate through a service interface, for example, the service interface provided by the AMF to the outside may be Namf; the service interface provided by the SMF can be Nsmf; the serving interface provided by the UDM can be Nudm, and the serving interface provided by the AF can be Naf; the serving interface provided by the PCF to the outside may be Npcf or the like.

The network element in fig. 2 is a reference point-based architecture, and does not limit the embodiment of the present application. Fig. 3 shows a schematic diagram of an architecture based on a servitization interface. As shown in fig. 3, the per-architecture includes: NSSF, AUSF, UDM, NEF, NRF, PCF, AF, AMF, SMF, UE, RAN, UPF, DN. In fig. 3, the external service interface provided by the NSSF may be NSSF, the external service interface provided by NEF may be Nnef, the external service interface provided by NRF may be nrrf, and the external service interface provided by AMF may be Namf; the service interface provided by the SMF can be Nsmf; the serving interface provided by the UDM can be Nudm, and the serving interface provided by the AF can be Naf; the external serving interface provided by the PCF may be Npcf, the external serving interface provided by the AUSF may be Nausf, and the external serving interface provided by the CHF may be Nchf; the interface between the control plane functions and the RAN and UPF is a non-serving interface. The UE is connected with the AMF through an N1 interface and is connected with the RAN through a Radio Resource Control (RRC) protocol; RAN is connected with AMF through an N2 interface, and RAN is connected with UPF through an N3 interface; the UPF is connected to the DN through an N6 interface, and the UPF is connected to the SMF through an N4 interface. For the related description, reference may be made to a 5G system architecture (5G system architecture) in the standard, and for brevity, the connection relationship of the architecture 300 is not described herein again.

In the embodiment of the present application, the general session establishment procedure may be described as follows: UE sends session establishing request to AMF through RAN, AMF selects SMF to provide service for the session, stores corresponding relation between SMF and PDU session, sends the session establishing request to SMF, SMF selects corresponding UPF for UE and establishes user plane transmission path, and allocates IP address for it. In the process, the SMF also initiates a policy control session establishment request to the PCF for establishing the policy control session between the SMF and the PCF, and in the process of establishing the policy control session, the SMF stores the corresponding relation between the policy control session and the PDU session. In addition, the AF can also establish an AF session with the PCF, and the PCF binds the AF session with the policy control session.

Taking the above-mentioned session establishment between the PCF and the SMF as an example, when the PCF is online, a registration request (e.g., NFRegister message) may be sent to the NRF, where the request message may carry network element information of itself, that is, NFProfile, and the network element information may further include recovery time, which is used to indicate a service recovery timestamp. When SMF interacts with PCF for the first time, it can also subscribe service state change of PCF to NRF, so that NRF can notify the information to SMF when judging that network element information of PCF is changed.

When a PCF network element experiences a device failure, a network exit, load balancing (a part of subscription data is migrated to a new device), etc., a session established between the PCF and the SMF may be affected, and when it is more serious, the PCF may lose information of the current session.

One current technique is that after a restart occurs, such as a failure restart, a planned restart, and a data cutover restart, the PCF may send updated network element information, that is, NFprofile, to the NRF through a registration message (e.g., NFRegister message) or an update message (e.g., NFUpdate message), where the network element information includes updated recoveryTime to indicate an updated service recovery timestamp. And the NRF judges that the recovery time in the network element information of the PCF changes, and then sends the updated network element information to the SMF network element subscribed with the PCF service state. After receiving the subscription notification, the SMF determines that the session before the time point needs to adopt a recovery mechanism based on the received recoveryTime, and triggers a corresponding mechanism, such as deactivating a user session and triggering the user to reestablish the session.

However, in the above method, the PCF can only indicate that the SMF is currently failed and restarted, migrated, or upgraded by carrying the updated reoverytime, but sessions lost in the actual failure and migration scenarios of the current network are usually in DNN granularity or slice granularity, and only target DNN or slice user sessions are affected, such as an Internet DNN session scenario migrated by the PCF, and an IP Multimedia System (IMS) DNN session on an old PCF is not affected, so the SMF does not need to trigger a session reestablishment procedure of the IMS DNN session. The existing method can cause that each notification triggers the reconstruction process of the whole user session under PCF, and generates great signaling waste to the core network.

The above description has been given taking the session between the PCF and the SMF as an example, but the problem exists in the scenarios such as the session between the PCF and the AMF, the CHF triggered PCF update, and the UDM triggered AMF/SMF update.

Based on the above, the present application provides a method for session reestablishment, so that it is expected that the session state of the faulty network element can be accurately sensed, and the session reestablishment can be performed quickly and accurately.

Fig. 4 shows an exemplary flowchart of the session reestablishment method of the present application. The session reestablishment method 400 is applied to the network architecture shown in fig. 2 or fig. 3 in the following manner, combining the steps.

S410, the first network element receives network element information of a second network element from the network storage function network element, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between the first network element and the second network element.

Optionally, the network element information further includes a first recovery time, and the session reestablishment between the first network element and the second network element according to the session feature information includes: and the first network element performs session reestablishment with the second network element according to the session characteristic information and the first recovery time.

Optionally, the method further includes: and the first network element determines that the second network element fails according to the first recovery time and the second recovery time, wherein the second recovery time is locally stored, and the second network element fails, including that the second network element itself fails and/or a link between the second network element and the application function network element fails.

Optionally, the method further includes: and the first network element subscribes the network element information of the second network element to the network storage function network element.

Optionally, the second network element is a policy control network element, and the first network element is an access and mobility management network element, a session management network element, or a network open network element; or the second network element is a unified data management network element, and the first network element is an access and mobility management network element, a session management network element, a short message service network element or an authentication server network element; or, the second network element is a unified data storage network element, and the first network element is a unified data management network element, a policy control network element or a network open network element.

And S420, the first network element and the second network element perform session reestablishment according to the session characteristic information.

In this embodiment, for a scenario where a second network element (also referred to as a server) has a server failure, data loss, an exception, and the like, a first network element (also referred to as a client) can accurately sense a session of the second network element (also referred to as a server) that is lost or an exception, and perform session reestablishment in a targeted manner.

And S510, the second network element sends the information of the registered network element to a network warehouse function network element NRF.

Specifically, the second network element may send a registration request (for example, an NFRegister message) to the NRF, where the request message may carry network element information of the second network element, that is, NFProfile, and the network element information may further include a second recovery time2 to indicate a service recovery timestamp.

S520, the first network element subscribes the network element information of the second network element to the NRF.

Specifically, the first network element may subscribe to the service state change of the second network element from the network repository function network element NRF when interacting with the second network element for the first time, so that the network repository function network element NRF notifies the first network element of the information when determining that the network element information of the second network element is changed.

S530, the first network element and the second network element establish a session.

The process may refer to the general session establishment procedure described above, and for brevity, will not be described herein again.

S540, the second network element determines that the second network element is faulty.

Specifically, the determining, by the second network element, of the self network element fault may include that the second network element has an equipment fault, quits the network, and the like, and optionally, along with the development of the technology, the determining may further include other possible self network element faults, which is not limited in the present application.

And S550, the second network element sends the network element information of the second network element to a network warehouse function network element NRF.

Specifically, after the failure is recovered, the second network element may send updated network element information, that is, NFprofile, to the NRF through a registration message (for example, an NFRegister message) or an update message (for example, an NFUpdate message), where the updated network element information includes session feature information, and the session feature information is used to indicate an affected session between the first network element and the second network element. Wherein the session feature information includes at least one of: a data network name DNN, network slice selection assistance information NSSAI and a public land mobile network identity PLMN ID.

In addition, the updated network element information may further include an updated recovery time, which may be referred to as a first recovery time1, for indicating an updated service recovery timestamp.

S560, the network warehouse function network element NRF sends the network element information of the second network element to the first network element.

Specifically, the network warehouse function network element NRF may determine, according to the updated recovery time included in the updated network element information, that is, the first recovery time1, that the first recovery time is different from the second recovery time stored locally, so as to determine that the network element information of the second network element is changed. Further, the updated network element information of the second network element is sent to the first network element subscribed to the service state of the second network element, and the updated network element information includes the session characteristic information.

And S560, the first network element and the second network element perform session reestablishment according to the session characteristic information.

Specifically, the first network element may determine the affected session quickly and accurately according to the data network name DNN, the network slice selection assistance information NSSAI, and the public land mobile network identifier PLMN ID in the session feature information, so as to perform session reestablishment, where a specific reestablishment process may refer to a specification in the current protocol, and this application does not introduce this.

It should be noted that the first network element and the second network element may represent a plurality of network elements, respectively, and the present application does not limit the network elements. For example, in a 5G system, the second network element may be a policy control network element PCF, and the first network element is an access and mobility management network element AMF, a session management network element SMF, or a network open network element NEF; or, the second network element may be a unified data management network element UDM, and the first network element is an access and mobility management network element AMF, a session management network element SMF, a short message service network element SMSF, or an authentication server network element AUSF; or, the second network element may be a unified data storage network element UDR, and the first network element is a unified data management network element UDM, a policy control network element PCF, or a network open network element NEF.

When the second network element is a Policy control network element PCF, session reestablishment refers to access management/session management Policy Association AM/SM Policy Association reestablishment; the session re-establishment may be a context re-establishment when the second network element is a unified data management network element, UDM.

In this embodiment, taking a voice call scenario as an example, a link failure between the second network element and the application function network element AF affects a voice call for a long time, and the first network element (also referred to as a client) can accurately sense a lost or abnormal session of the second network element (also referred to as a server), and perform session reconstruction in a targeted manner, thereby ensuring that a subsequent voice call is normal. The scheme is also applicable to a non-voice call scene, the application does not limit the non-voice call scene, and the specific flow is similar to the following method and is not described herein again.

S610, S620, and S630 are the same as S510, S520, and S530, and are not described herein again.

And S640, the user initiates a voice call, the second network element receives a (receiving, rx)/N5 message, triggers and binds successfully, and meanwhile, the front end establishes a special bearer.

S650, the voice call fails, i.e. the Rx message or the N5 message of the voice call cannot reach the second network element, resulting in voice impairment. The Rx message corresponds to a scenario in which a Diameter protocol is used between the IMS AF and the PCF, and the N5 message corresponds to a scenario in which a hypertext transfer protocol (HTTP) protocol is used between the IMS AF and the PCF.

S660, the second network element determines a link failure with the application function AF.

And S670, the second network element sends the network element information of the second network element to a network warehouse function network element NRF.

Meanwhile, the network element information can also be used for indicating deletion of an IMS DNN corresponding to the voice session, so that the first network element directs the newly online IMS session to an updated second network element, and subsequent call failure caused by the fact that the new IMS session is established on the second network element which is not updated is avoided.

S680, the network warehouse function network element NRF sends the network element information of the second network element to the first network element.

Specifically, the network warehouse function network element NRF may determine, according to the updated recovery time included in the updated network element information, that is, the first recovery time1, that the first recovery time is different from the second recovery time stored locally, so as to determine that the network element information of the second network element is changed. Further, the updated network element information of the second network element is sent to the first network element that subscribes to the service state of the second network element, and the updated network element information includes the session feature information.

And S690, the first network element and the second network element perform session reestablishment according to the session characteristic information.

Specifically, the first network element may quickly and accurately determine the affected session according to the data network name DNN, the network slice selection assistance information NSSAI, and the public land mobile network identifier PLMN ID in the session feature information, so as to perform session reestablishment. For example, in this embodiment, the first network element may determine the affected session based on IMS DNN, perform session re-establishment without affecting the network Internet data session. The specific reconstruction process may refer to the specification in the current protocol, and the description thereof is omitted here.

When the network element information is used for indicating deletion of IMS DNN, so that the first network element points the newly online IMS session to an updated second network element, the first network element and the updated second network element perform session reestablishment according to the session characteristic information, and the situation that the new IMS session is established on the second network element which is not updated, and subsequent calling fails is avoided.

It should be noted that the first network element and the second network element may represent a plurality of network elements, and specific situations thereof may refer to the description in fig. 5, and for brevity, detailed description is not repeated herein.

It should be understood that, the sequence numbers of the above processes do not imply any order of execution, and the order of execution of the processes should be determined by their functions and inherent logic, and should not limit the implementation process of the embodiments of the present application in any way.

It is also to be understood that the terminology and/or the description of the various embodiments herein is consistent and mutually inconsistent if no specific statement or logic conflicts exists, and that the technical features of the various embodiments may be combined to form new embodiments based on their inherent logical relationships.

It is to be understood that, in the above embodiments of the present application, the method implemented by the communication device may also be implemented by a component (e.g., a chip or a circuit) that can be configured inside the communication device.

The method for session reestablishment provided by the embodiment of the present application is described in detail above with reference to fig. 4 to 6. The session reestablishment method is introduced mainly from the interaction perspective between network elements. It will be understood that each network element, in order to implement the above-described functions, comprises corresponding hardware structures and/or software modules for performing the respective functions. Those of skill in the art would appreciate that the various illustrative components and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

Hereinafter, a session reestablishing apparatus according to an embodiment of the present application is described in detail with reference to fig. 7 and 8. It should be understood that the description of the apparatus embodiment corresponds to the description of the method embodiment, and therefore, for the sake of brevity, some details are not repeated herein.

In the embodiment of the present application, the functional modules may be divided according to the above method example for the transmitting end device or the receiving end device, for example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, in the embodiment of the present application, the division of the module is schematic, and is only one logic function division, and another division manner may be available in actual implementation. The following description will be given taking the example of dividing each functional module corresponding to each function.

Fig. 7 shows an exemplary block diagram of a session reestablishment apparatus according to the present application. Any network element, such as the first network element, the second network element, etc., involved in any one of the methods 400 to 600 described above may be implemented by the session reestablishment apparatus shown in fig. 7.

It should be understood that the session reestablishment apparatus 700 may be a physical apparatus, may be a component (e.g., an integrated circuit, a chip, etc.) of the physical apparatus, and may be a functional module in the physical apparatus.

As shown in fig. 7, the session reestablishment apparatus 700 includes: one or more processors 710. Processor 710 may store execution instructions for performing the methods of embodiments of the present application. Optionally, an interface may be called in the processor 710 to implement the receiving and sending functions. The interface may be a logical interface or a physical interface, which is not limited in this regard. For example, the interface may be a transceiver circuit, or an interface circuit. The transceiver circuitry, or interface circuitry, used to implement the receive and transmit functions may be separate or integrated. The transceiver circuit or the interface circuit may be used for reading and writing code/data, or the transceiver circuit or the interface circuit may be used for transmitting or transferring signals.

Alternatively, the interface may be implemented by a transceiver. Optionally, the session reestablishment apparatus 700 may further include a transceiver 730. The transceiver 730 may be referred to as a transceiver unit, a transceiver, a transceiving circuit or a transceiver, etc. for implementing transceiving function.

Optionally, the session reestablishment apparatus 700 may further include a memory 720. The specific disposition location of the memory 720 is not particularly limited in the embodiments of the present application, and the memory may be integrated with the processor or may be independent of the processor. For the case that the session reconstruction apparatus 700 does not include a memory, the session reconstruction device 700 may have a processing function, and the memory may be disposed in other locations (e.g., a cloud system).

Processor 710, memory 720, and transceiver 730 communicate control and/or data signals with each other via the interconnection paths.

It is to be understood that, although not shown, the session reestablishment apparatus 700 may further include other devices, such as an input device, an output device, a battery, etc.

Optionally, in some embodiments, the memory 720 may store execution instructions for performing the methods of the embodiments of the present application. The processor 710 may execute the instructions stored in the memory 720 to perform the steps of the method described below in combination with other hardware (e.g., the transceiver 730), and the specific working process and advantages may refer to the description of the method embodiments above.

The method disclosed in the embodiment of the present application may be applied to the processor 710, or may be implemented by the processor 710. Processor 710 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the method may be performed by instructions in the form of hardware integrated logic circuits or software in a processor. The processor may be a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off the shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, or discrete hardware components. The various methods, steps, and logic blocks disclosed in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software modules may be located in a Random Access Memory (RAM), a flash memory, a read-only memory (ROM), a programmable ROM, an electrically erasable programmable ROM, a register, or other storage medium known in the art. The storage medium is located in a memory, and a processor reads instructions in the memory and combines hardware thereof to complete the steps of the method.

It will be appreciated that the memory 720 can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory ROM, a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. Volatile memory can be random access memory, RAM, which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM, enhanced SDRAM, SLDRAM, synchronous Link DRAM (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

Optionally, the specific form of the session reestablishing apparatus 800 may be a general-purpose computer device or a chip in a general-purpose computer device, which is not limited in this embodiment of the present application. As shown in fig. 8, the session reestablishment apparatus includes a processing unit 810 and a transceiving unit 820.

Specifically, the session reestablishing apparatus 800 may be any network element related to this application, and may implement the functions that can be implemented by this network element. It should be understood that the session reestablishing apparatus 800 may be a physical device, a component (e.g., an integrated circuit, a chip, etc.) of the physical device, or a functional module in the physical device.

In a possible design, the session reestablishing apparatus 800 may be the first network element apparatus in the foregoing embodiment, or may be a chip for implementing the function of the first network element apparatus in the foregoing embodiment.

For example, the transceiving unit 820 is configured to receive network element information of a second network element from a network storage function network element, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between a first network element and the second network element; a processing unit 810, configured to perform session reestablishment with the second network element according to the session feature information.

The transceiver 810 is specifically configured to perform session reestablishment with the second network element according to the session characteristic information and the first recovery time.

Optionally, the processing unit 810 is further configured to determine that the second network element fails according to the first recovery time and a second recovery time, where the second recovery time is locally stored, and the second network element failing includes that the second network element itself fails and/or a link between the second network element and an application function network element fails.

Optionally, the transceiving unit 820 is further configured to subscribe the network element information of the second network element to the network storage function network element.

It should also be understood that, when the session reestablishment apparatus 800 is the first network element device, the transceiver 820 in the session reestablishment apparatus 800 may be implemented by a communication interface (such as a transceiver or an input/output interface), and the processing unit 810 in the session reestablishment apparatus 800 may be implemented by at least one processor, for example, may correspond to the processor 710 shown in fig. 7.

Optionally, the session reestablishing apparatus 800 may further include a storage unit, and the storage unit may be configured to store instructions or data, and the processing unit may call the instructions or data stored in the storage unit to implement the corresponding operation.

It should be understood that the specific processes of the units for executing the corresponding steps are already described in detail in the above method embodiments, and therefore, for brevity, detailed descriptions thereof are omitted.

In another possible design, the session reestablishing apparatus 800 may be the second network element apparatus in the foregoing embodiment, or may be a chip for implementing the function of the second network element in the foregoing embodiment.

For example, the transceiver 820 is configured to send network element information of a second network element to a network storage function network element, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between the second network element and a first network element; a processing unit 810, configured to perform session reestablishment with the first network element according to the session feature information.

The processing unit 810 is specifically configured to perform session reestablishment with the first network element according to the session feature information and the first recovery time.

Optionally, the processing unit 810 is further configured to determine that the second network element itself fails and/or a link between the second network element and an application function network element fails.

Optionally, the transceiver 820 is further configured to register the network element information of the second network element with the network storage function network element, where the network element information includes a second recovery time, and the second recovery time is locally stored.

It should also be understood that, when the session reestablishment apparatus 800 is a second network element apparatus, the transceiver unit 820 in the session reestablishment apparatus 800 may be implemented by a communication interface (such as a transceiver or an input/output interface), for example, may correspond to the communication interface 730 shown in fig. 7, and the processing unit 810 in the session reestablishment apparatus 800 may be implemented by at least one processor, for example, may correspond to the processor 710 shown in fig. 7.

It should also be understood that the apparatus 800 may also be used to implement the functions of network elements such as SMF, AMF, etc. in the above method embodiments, where the transceiver 820 may be used to implement operations related to receiving and transmitting, and the processing unit 810 may be used to implement operations other than receiving and transmitting, which may specifically refer to the description in the above method embodiments and are not listed here.

In addition, in the present application, the session reestablishing apparatus 800 is presented in the form of a functional module. As used herein, a "module" may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that may provide the described functionality. In a simple embodiment, those skilled in the art will appreciate that the apparatus 800 may take the form shown in FIG. 8. The processing unit 810 may be implemented by the processor 710 shown in fig. 7. Alternatively, if the computer device shown in fig. 7 includes the memory 720, the processing unit 810 may be implemented by the processor 710 and the memory 720. The transceiving unit 820 may be implemented by the transceiver 730 shown in fig. 7. The transceiver 730 includes a receiving function and a transmitting function. In particular, the processor is implemented by executing a computer program stored in the memory. Alternatively, when the apparatus 800 is a chip, the functions and/or implementation processes of the transceiving unit 820 can also be implemented by pins or circuits, etc. Alternatively, the memory may be a storage unit in the chip, such as a register, a cache, or the like, and the storage unit may also be a storage unit in the computer device that is located outside the chip, such as the memory 720 shown in fig. 7, or may also be a storage unit disposed in another system or device, which is not in the computer device. Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the technical solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

Various aspects or features of the present application may be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques. The term "article of manufacture" as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disk, floppy disk, or magnetic tape), optical disks (e.g., compact Disk (CD), digital Versatile Disk (DVD), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROM), card, stick, or key drive, etc.). In addition, various storage media described herein can represent one or more devices and/or other machine-readable media for storing information. The term "machine-readable medium" can include, without being limited to, wireless channels and various other media capable of storing, containing, and/or carrying instruction(s) and/or data.

According to the method provided by the embodiment of the present application, the present application further provides a computer program product, which includes: computer program code which, when run on a computer, causes the computer to perform the method of any one of the embodiments shown in figures 4 to 6.

According to the method provided by the embodiment of the present application, a computer-readable medium is further provided, and the computer-readable medium stores program codes, and when the program codes are executed on a computer, the computer is caused to execute the method of any one of the embodiments shown in fig. 4 to 6.

According to the method provided by the embodiment of the application, the application also provides a system which comprises the device or the equipment.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that includes one or more available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a Digital Video Disc (DVD)), or a semiconductor medium (e.g., a Solid State Disc (SSD)), among others.

As used in this specification, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, firmware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components can reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. The components may communicate by way of local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from two components interacting with another component in a local system, distributed system, and/or across a network such as the internet with other systems by way of the signal).

It should also be understood that the term "and/or" herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It should also be understood that the numbers "first", "second", and the like in the embodiments of the present application are introduced only for distinguishing different objects, for example, for distinguishing different "information", or "device", or "unit", and the understanding of the specific object and the corresponding relationship between different objects should be determined by the functions and the inherent logic thereof, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, 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 units is only one type of logical functional division, and other divisions may be realized in practice, for example, multiple units or components may be combined or 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 functions may be stored in a computer-readable storage medium if they are implemented in the form of software functional units and sold or used as separate products. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) 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: a U-disk, a portable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, an optical disk, or other various media capable of storing program codes.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for session reestablishment, comprising:

a first network element receives network element information of a second network element from a network storage function network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating an affected session between the first network element and the second network element;

and the first network element and the second network element perform session reconstruction according to the session characteristic information.

2. The method of claim 1, wherein the session feature information comprises at least one of:

a data network name DNN, network slice selection assistance information NSSAI and a public land mobile network identity PLMN ID.

3. The method according to claim 1 or 2, characterized in that the network element information further comprises a first recovery time,

the first network element performs session reestablishment with the second network element according to the session characteristic information, including:

and the first network element and the second network element perform session reconstruction according to the session characteristic information and the first recovery time.

4. The method of claim 3, further comprising:

and the first network element determines that the second network element fails according to the first recovery time and a second recovery time, wherein the second recovery time is locally stored, and the second network element failure includes the second network element self failure and/or a link between the second network element and an application function network element failure.

5. The method according to any one of claims 1 to 4, further comprising:

and the first network element subscribes the network element information of the second network element to the network storage function network element.

6. The method according to any one of claims 1 to 5,

the second network element is a policy control network element, and the first network element is an access and mobility management network element, a session management network element or a network open network element; or,

7. A method for session reestablishment, comprising:

the second network element sends network element information to a network storage function network element, wherein the network element information comprises session characteristic information, and the session characteristic information is used for indicating an affected session between the second network element and the first network element;

and the second network element performs session reconstruction with the first network element according to the session characteristic information.

8. The method of claim 7, wherein the session feature information comprises at least one of:

9. The method according to claim 7 or 8, characterized in that the network element information further comprises a first recovery time,

the second network element performs session reestablishment with the first network element according to the session feature information, including:

and the second network element performs session reconstruction with the first network element according to the session characteristic information and the first recovery time.

10. The method of claim 9, further comprising:

and the second network element determines that the second network element has a fault and/or a link between the second network element and an application function network element has a fault.

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

and the second network element registers the network element information of the second network element with the network storage function network element, wherein the network element information comprises second recovery time, and the second recovery time is locally stored.

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

13. An apparatus for session reestablishment, comprising:

a receiving unit, configured to receive network element information of a second network element from a network storage function network element, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between a first network element and the second network element;

and the processing unit is used for carrying out session reconstruction with the second network element according to the session characteristic information.

14. The apparatus of claim 13, wherein the session feature information comprises at least one of:

15. The apparatus according to claim 13 or 14, wherein the network element information further comprises a first recovery time,

the processing unit is specifically configured to perform session reestablishment with the second network element according to the session feature information and the first recovery time.

16. The apparatus of claim 15, wherein the processing unit is further configured to determine that the second network element fails according to the first recovery time and a second recovery time, the second recovery time is locally saved, and the second network element failure includes a failure of the second network element itself and/or a failure of a link between the second network element and an application function network element.

17. The apparatus according to any of claims 13 to 16, wherein the transceiver unit is further configured to subscribe to the network element information of the second network element from the network storage function network element.

18. The apparatus of any one of claims 13 to 17,

19. An apparatus for session reestablishment, comprising:

a transceiver unit, configured to send network element information of a second network element to a network storage function network element, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between the second network element and a first network element;

and the processing unit is used for carrying out session reconstruction with the first network element according to the session characteristic information.

20. The apparatus of claim 19, wherein the session feature information comprises at least one of:

21. The apparatus according to claim 19 or 20, wherein the network element information further comprises a first recovery time,

the processing unit is specifically configured to perform session reestablishment with the first network element according to the session feature information and the first recovery time.

22. The apparatus of claim 21, wherein the processing unit is further configured to determine that the second network element itself fails and/or that a link between the second network element and an application function network element fails.

23. The apparatus according to any one of claims 19 to 22, wherein the transceiver unit is further configured to register the network element information of the second network element with the network storage function network element, where the network element information includes a second recovery time, and the second recovery time is locally stored.

24. The apparatus of any one of claims 19 to 23,

25. A communication system comprising a first network element, a second network element;

the second network element is configured to send network element information, where the network element information includes session feature information, and the session feature information is used to indicate an affected session between the second network element and the first network element;

and the first network element is used for receiving the network element information and carrying out session reconstruction with the second network element according to the session characteristic information.

26. The system of claim 25, wherein the system further comprises a network storage function network element,

the network storage function network element is used for receiving the network element information from the second network element; and sending the network element information to the first network element, wherein the network element information includes session characteristic information, and the session characteristic information is used for indicating the session affected between the second network element and the first network element.