CN114071491A

CN114071491A - Session service request method and device

Info

Publication number: CN114071491A
Application number: CN202010754112.1A
Authority: CN
Inventors: 文振忠; 周水生
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2022-02-18
Anticipated expiration: 2040-07-30
Also published as: CN114071491B

Abstract

The invention provides a session service request method and a device, wherein the method comprises the following steps: sending a Protocol Data Unit (PDU) session update request message to the SMF, and receiving a PDU session update response message returned by the SMF; when determining that the PDU session updating request fails, sending a session establishing request message to the SMF to request to allocate session signaling resources and session service resources to User Equipment (UE); and after receiving a response message of successfully creating the session returned by the SMF, sending an initial context establishment request message to a Radio Access Network (RAN) entity. By utilizing the method provided by the invention, under the condition that the SMF network element resource is failed or insufficient to cause the returned response message for modifying the session failure, the service request flow of the UE can be successfully processed at one time, the network resource consumption is less, and the problem that the user cannot access for a long time due to network congestion caused by the reciprocating flow endless loop of the message between the UE and the AMF is solved.

Description

Session service request method and device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a session service request method and apparatus.

Background

Under the 5G mobile communication Network architecture, a wireless communication system is composed of a RAN (Radio Access Network) and a 5GC Core Network (5G Core Network). The radio Access network is implemented by a RAN entity, And the core network is implemented by an AMF (Access And Mobility Management Function) entity, an SMF (Session Management Function) entity, And a UPF (User Plane Function) entity. The AMF entity device plays a very important role as a mobility management entity of a 5GC core network.

During 5G large-scale test, the problem that the UE signals of the user terminal are full, but the network cannot be accessed occurs. Analyzing the signaling flow, and finding out the reason that when the UE sends the service request to the AMF, the AMF replies the service request rejection, then the UE continues to send the service request, and the AMF continues to reply the service request rejection, so that the UE cannot surf the internet normally. The reason for analyzing the AMF reply service rejection deeply is that the SMF network element has a short-term failure, which causes the context of the user including the session context to be lost completely, so that a pdu session update response pdu update response failure message is replied to the AMF, which causes the AMF to reply the service rejection to the UE.

Therefore, a mechanism for improving the success rate of the UE service request in the 5GC system is needed to solve the problem that the messages between the UE and the AMF entity of the network device reciprocate back and forth in the above scenario, so that the flow is in a loop, and further, the network congestion is caused and the UE cannot be accessed for a long time.

Disclosure of Invention

The invention provides a session service request method and a session service request device, which are used for solving the problems that the flow is in endless circulation due to the back and forth of messages between UE and an AMF entity of network equipment, so that network congestion is caused and the UE cannot be accessed for a long time.

The first aspect of the present invention provides a session service request method, applied to an AMF entity, including:

sending a Protocol Data Unit (PDU) session update request message to the SMF, and receiving a PDU session update response message returned by the SMF;

when determining that the PDU session updating request fails, sending a session establishing request message to the SMF to request to allocate session signaling resources and session service resources to User Equipment (UE);

and after receiving a response message of successfully creating the session returned by the SMF, sending an initial context establishment request message to a Radio Access Network (RAN) entity.

Optionally, after sending the initial context setup request message to the RAN entity of the radio access network, the method further includes:

receiving an initial context establishment success response message returned by the RAN, and retransmitting the PDU session update request message to the SMF;

and receiving a PDU session update response message returned by the SMF.

Optionally, the create session request message includes any one or more of the following:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

Optionally, the creating a session response message includes:

and creating a result code of successful establishment of the initial context, wherein the result code comprises PDU session identification, a service quality flow identifier, service quality configuration information, service tunnel information distributed to the session by the SMF, single network slice selection auxiliary information and an N1 reference point set.

Optionally, the initial context setup request message includes any one or more of the following:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

Optionally, the initial context setup success response message is N2 reference point information, and the N2 reference point information includes: the base station distributes the service tunnel information and the received service quality configuration information for the session.

A second aspect of the present invention provides a session service request method, which is applied to an SMF entity, and the method includes:

receiving a Protocol Data Unit (PDU) session update request message sent by an AMF;

executing a session updating process, and sending a PDU session updating response message to the AMF;

receiving a session creation request message sent by the AMF when the PDU session update request is determined to fail, and allocating session signaling resources and session service resources for the UE;

a successfully created session response message is returned to the AMF to cause the AMF to send an initial context request message to the RAN.

Optionally, after sending the initial context request message to the RAN, the AMF further includes:

and receiving the PDU session update request message, and returning a PDU session update response message to the AMF.

Optionally, the creating session request message carries any one or more of the following contents:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

protocol data unit user identification PDU;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

Optionally, the create session response message includes any one or more of the following:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

Optionally, the initial context setup success response message N2 reference point information, the N2 reference point information including: the base station distributes the service tunnel information and the received service quality configuration information for the session.

A third aspect of the present invention provides an AMF entity apparatus, comprising:

a memory to store instructions;

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

when determining that the PDU session updating request fails, sending a session establishing request message to the SMF to request to allocate session signaling resources and session service resources to the UE;

and receiving a response message of successfully creating the session returned by the SMF, and sending an initial context establishment request message to a radio access network RAN entity.

Optionally, after the processor sends the initial context setup request message to the RAN entity of the radio access network, the method further includes:

after receiving the initial context establishment success response message returned by the RAN, retransmitting the PDU session update request message to the SMF;

and receiving a PDU session update response message returned by the SMF.

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

Optionally, the creating a session response message includes:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

A fourth aspect of the present invention provides an SMF entity apparatus, including:

a memory to store instructions;

Optionally, after the AMF sends the initial context request message to the RAN, the method further includes:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

A fifth aspect of the present invention provides a session service request apparatus, including:

the request receiving unit is used for receiving a Protocol Data Unit (PDU) session updating request message sent by the AMF;

the request response unit is used for executing the session updating process and sending a PDU session updating response message to the AMF;

an initial context request unit, configured to receive a session creation request message sent by the AMF when determining that the PDU session update request fails, and allocate session signaling resources and session service resources to the UE;

Optionally, the initial context requesting unit is configured to, after sending the initial context setup request message to the RAN entity of the radio access network, further include:

and receiving a PDU session update response message returned by the SMF.

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

Optionally, the creating a session response message includes:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

A sixth aspect of the present invention provides a session service request apparatus, including:

Optionally, the request receiving unit is configured to, after the AMF sends the initial context request message to the RAN, further include:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

A seventh aspect of the present invention provides a computer storage medium having stored thereon a computer program which, when executed by a processor, implements any of the methods provided by the first aspect of the present invention, or which, when executed by a processor, implements any of the methods provided by the first aspect of the present invention.

By utilizing the method provided by the invention, under the condition that the SMF network element resource is failed or insufficient to cause the returned response message for modifying the session failure, the service request flow of the UE can be successfully processed at one time, the network resource consumption is less, and the problem that the user cannot access for a long time due to network congestion caused by the reciprocating flow endless loop of the message between the UE and the AMF is solved.

Drawings

FIG. 1 is a schematic diagram of a 5G system architecture;

FIG. 2 is a flowchart of registration when a UE is powered on;

FIG. 3 is a flow chart of a session establishment request;

FIG. 4 is a flow chart of the N2 release;

FIG. 5 is a flow chart of steps of a method of session service request;

FIG. 6 is a complete flow diagram of a session service request method;

FIG. 7 is a schematic diagram of an AMF physical device structure;

fig. 8 is a schematic structural diagram of an SMF entity device;

FIG. 9 is a diagram of a session service request device unit;

fig. 10 is a diagram of another session service request apparatus unit.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The technical scheme provided by the embodiment of the application can be suitable for various systems, particularly 5G systems. For example, the applicable system may be a global system for mobile communication (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (GPRS) system, a Long Term Evolution (LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD), a Universal Mobile Telecommunications System (UMTS), a universal microwave Access (WiMAX) system, a 5G NR system, and the like. These various systems include terminal devices and network devices.

The terminal device referred to in the embodiments of the present application may refer to a device providing voice and/or data connectivity to a user, a handheld device having a wireless connection function, or other processing device connected to a wireless modem. The names of the terminal devices may also be different in different systems, for example, in a 5G system, the terminal devices may be referred to as User Equipments (UEs). Wireless terminal devices, which may be mobile terminal devices such as mobile telephones (or "cellular" telephones) and computers with mobile terminal devices, e.g., mobile devices that may be portable, pocket, hand-held, computer-included, or vehicle-mounted, communicate with one or more core networks via the RAN. Examples of such devices include Personal Communication Service (PCS) phones, cordless phones, Session Initiated Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), and the like. The wireless terminal device may also be referred to as a system, a subscriber unit (subscriber unit), a subscriber station (subscriber station), a mobile station (mobile), a remote station (remote station), an access point (access point), a remote terminal device (remote terminal), an access terminal device (access terminal), a user terminal device (user terminal), a user agent (user agent), and a user device (user device), which are not limited in this embodiment of the present application.

The network device according to the embodiment of the present application may be a base station, and the base station may include a plurality of cells. A base station may also be referred to as an access point, or a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminal devices, or by other names, depending on the particular application. The network device may be configured to interconvert received air frames with Internet Protocol (IP) packets as a router between the wireless terminal device and the rest of the access network, which may include an Internet Protocol (IP) communication network. The network device may also coordinate attribute management for the air interface. For example, the network device according to the embodiment of the present application may be a Base Transceiver Station (BTS) in a global system for mobile communications (GSM) or a Code Division Multiple Access (CDMA), may also be a network device (NodeB) in a Wideband Code Division Multiple Access (WCDMA), may also be an evolved network device (eNB or e-NodeB) in a Long Term Evolution (LTE) system, a 5G base station in a 5G network architecture (next generation system), and may also be a home evolved node B (HeNB), a relay node (relay node), a home base station (femto), a pico base station (pico), and the like, which are not limited in the embodiments of the present application.

As shown in fig. 1, which is a schematic diagram of a 5G system architecture, a wireless communication system is composed of a RAN and a 5GC Core Network (5G Core Network). The radio access network is realized by a RAN entity, the core network is realized by an AMF entity, an SMF entity, a UPF (User Plane Function) entity, etc., and mainly includes a RAN and a 5G core network,

the 5G system architecture includes the following reference points:

n1 denotes a reference point between the UE and the AMF;

n2 denotes the reference point between (R) AN and AMF;

n3 represents the reference point between (R) AN and UPF;

n4 represents a reference point between SMF and UPF;

n6 represents a reference point between the UPF and the data network.

The RAN entity may be a 3gpp access network (e.g., LTE, 5G-NR) or a non-3gpp access network.

The user plane functional entity UPF has the main functions of routing forwarding and Qos flow mapping of data packets.

The policy control function entity PCF supports a unified policy framework to manage network behaviors, provides policy rules for the network entity to implement execution, accesses subscription information of a Unified Data Repository (UDR), and the PCF can only access NDR of the same PLMN.

The network elements of the network exposure functional entities NEF and 3gpp all expose the capability of the network elements to other network elements through the NEF, the NEF stores relevant information into the NDR and can also acquire the relevant information from the NDR, and the NEF can only access the NDR of the same PLMN; the NEF provides corresponding security guarantee to ensure the security of the external application to the 3gpp network; the conversion of 3gpp internal and external related information, such as the conversion of AF-Service-Identifier and DNN, S-NSSAI, etc. inside the 5G core network, especially the sensitive information of the network and the user must be hidden from the external network elements; the NEF can acquire the relevant information of other network elements by accessing the NDR, and the NEF can only access the UDR of the same PLMN.

A network storage function entity NRF supporting a service Discovery function, namely receiving NF-Discovery-Request sent by a network element and then providing discovered network element information to a Request party; maintaining the characteristics of the available network element instances and the service capabilities supported by the network element instances; the characteristic parameters of a network element mainly include: { network element instance ID, network element type, PLMN, associated ID of network slice (e.g., S-NSSAI, NSI ID), IP or domain name of network element, capability information of network element, name of service capability supported, etc }.

The Unified Data Management (UDM) entity is responsible for the following main functions: generating a 3gpp authentication certificate/authentication parameter; storing and managing a permanent user id (supi) of the 5G system; managing subscription information; MT-SMS delivery; SMS management; and (3) registration management of a service network element of the user (such as AMF, SMF and the like which currently provide services for the terminal).

And the authentication server network element AUSF supports the authentication of the 3gpp access and the authentication of the unregusted non3gpp access.

The AMF entity is a termination point of a RAN signaling interface (N2 interface), a termination point of NAS (N1 interface) signaling (MM message) is responsible for functions of encryption and complete protection of the NAS message, registration, access, mobility, authentication, short message transmission and the like, and is also responsible for allocation of an Eps bearer ID when interacting with an Evolved Packet System (EPS) network.

The main functions of SMF entities are: the termination points of the NAS message and the SM message; establishing, modifying and releasing a session; allocating and managing UE IP; a Dynamic Host Configuration Protocol (DHCP) function; an Address Resolution Protocol (ARP) proxy or an IPv6 neighbor solicitation proxy; selecting and controlling a UPF for a session; collecting charging data and supporting a charging interface; determining a session and service continuity mode (SSC) mode for a session; downlink data indication, and the like.

The main functions of the UPF entity are responsible for routing forwarding and Qos flow mapping of data packets.

Specifically, when the UE sends a service request to the AMF, the AMF will respond to the service request and reply the request to the UE, when the AMF replies to the service request rejection, the UE needs to continue to send the service request, and the AMF continues to reply to the service request rejection, which results in that the UE cannot surf the internet normally, and the request reply action will be repeated many times until the AMF starts a protection mechanism, initiates de-registration, reestablishes the session, and cannot surf the internet and perform a call service normally, and the AMF replies to the service rejection because a SMF network element has a transient failure or insufficient gateway resources, which results in that the context of the user, including the session context, is all lost, so that a protocol data unit session update response failure message is replied to the AMF, which further results in that the AMF replies to the UE with the service rejection.

After the above scenario is triggered, a message loop reciprocating back and forth is formed between the UE and the RAN, between the RAN and the AMF, and between the AMF and the SMF, and messages between the UE and the network interact back and forth, which causes a message reciprocating dead cycle between the UE and the core network element AMF, which cannot be stopped all the time. A large number of NAS messages are transmitted through the air interface resources of the RAN, which causes a great waste of NR air interface resources, and a large number of bursts of messages may also cause network paralysis.

Secondly, the user can not really access the network all the time, the user can not surf the internet and download the network, and can not enjoy any function provided by the 5GC network, the terminal user can only shut down the terminal user in advance and then restart the terminal user, the step of re-registering the terminal user to the network is triggered by the action of restarting the terminal user, and other communication services such as surfing the internet and the like can not be continued until the terminal user successfully registers the terminal user, so that the user experience is poor.

Fig. 2 shows a process of registering a UE when the UE is powered on, which mainly includes the following steps:

step 1, UE sends conversation Request message to (R) AN;

step 2, (R) the AN carries out AMF Selection (AMF Selection) solution according to the session request message;

step 3, (R) AN sends Registration Request message to new AMF;

step 4, the new AMF sends a complete registration request Namf _ Communication _ UEContext Transfer message to the old AMF;

step 5, the old AMF sends a complete registration Response Namf _ Communication _ UEContext Transfer Response message to the new AMF;

step 6, the new AMF sends an Identity Request message to the UE:

step 7, the UE sends an Identity Response message to the new AMF;

step 8, the AMF may decide to initiate UE authentication by calling AUSF (AU SF selectionAUSF). In this case, the AMF selects SUPI or SUCI based AUSF.

Step 9, if verification is needed, AMF requests verification (Authentication/Security) from AUSF; if there is a tracking requirement on the AMF for the UE, the AMF will provide the tracking requirement to the AUSF in its request.

If the NAS security context does not exist, a NAS security boot is performed.

If the 5G-AN has requested UE context, the AMF initiates AN NGAP procedure to provide the 5G-AN with the security context specified in TS 38.413[10 ].

The 5G-AN stores the security context and confirms to the AMF.

Step 10, the new AMF sends a complete registration completion notification to the old AMF: namf _ Communication _ Registration Complete notification message;

if the AMF has changed, the new AMF notifies the old AMF that the registration of the UE in the new AMF has been completed by calling a Namf _ Communication _ registration complete notification service operation. If the authentication/security procedure fails, Registration should be rejected and the new AMF calls the Namf _ Communication _ Registration Complete Notify service operation to the old AMF using the reject indication reason code. The old AMF continues as if the UE context transfer service operation was never received.

Step 11, the new AMF sends an Identity Request/Response message to the UE;

step 12, the new AMF starts ME Identity Check by calling N5g-eir Equipment Identity Check N5g-eir _ Equipment Identity Check _ Get service operation;

step 13, if step 14 is to be performed, the new AMF based on SUPI selects UDM (udmselection), and then UDM may select UDR instance.

If the AMF has changed since the last Registration procedure, or the SUPI provided by the UE does not refer to the active context in the AMF, or if the UE is registered to the same AMF, it is already registered to a non3GPP access (i.e. the UE registers through a non3GPP access and initiates this Registration procedure to add the 3GPP access), the new AMF registers with the UDM using a numdm UECM Registration message (numdm UECM Registration), and the user notifies when the UDM de-registers the AMF, steps 14 a-c. The UDM stores the AMF identities associated with the access types and does not delete AMF identities associated with other access types. The UDM may store information provided by the Nudr _ DM _ Update when it is registered in the UDR. The new AMF sends a Nudm _ SDM Get message (Nudm _ SDM _ Get) to the UDM, and the new AMF sends a Nudm _ SDM Subscribe message (Nudm _ SDM _ Subscribe) to the UDM;

step 14d, the AMF may remove the UE context when the timer expires (numm _ UECM _ registration notification);

step 14e, the Old AMF sends a Nudm _ SDM unsubscribe message (Nudm _ SDM _ unsubscribe) to the UDM;

step 15, the new AMF selects pcf (pcf selection);

step 16, the new AMF executes AM Policy Association Establishment (AM Policy Association Establishment);

step 17, the AMF sends the session Update SM Context (Nsmf _ PDU _ Update SM Context)/Nsmf _ PDU session Release SM Context (Nsmf _ PDU _ Release SM Context) to the SMF.

Step 18, the new AMF sends a N2AMF Mobility request (N2 AMF Mobility requests) to the N3 IWF.

Step 19, N2AMF Mobility Response of N3IWF to new AMF (N2 AMF Mobility Response);

step 20, old AMF to (V-) PCF: AMF-initiated Policy Association Termination (AMF-initiated UE Policy Association Termination);

step 21, the AMF sends a Registration Accept (Registration Accept) message to the UE indicating that the Registration request has been accepted;

step 22, the UE sends a Registration Complete message to the new AMF;

step 23, AMF to UDM: if the access and mobile user data provided by the UDM to the AMF in 14b includes a roaming information indication indicating that the UDM requests acknowledgement of receipt of this information from the UE, the AMF provides the UE with a Nudm _ SDM _ Info for acknowledgement of the UDM.

The AMF also provides confirmation to the UDM that the UE received and acted upon a network fragment user change indication using the Nudm _ SDM _ Info service operation.

Step 24, the AMF sends a numdm UECM Update message to the UDM.

After the UE is registered in the above manner, the UE can send a PDU session establishment request to the AMF to complete a session establishment function, specifically, as shown in fig. 3, it is a session establishment request flowchart, where in step 3, a context establishment request from the AMF to the SMF is made;

step 5, creating a response to the AMF context for the SMF;

step 15, updating the context request from AMF to SMF;

step 17, update response for SMF to AMF context.

The other steps in fig. 3 are common steps in the session establishment request, and those skilled in the art should understand that the description is omitted here.

However, due to the relative shortage of radio resources, the 5G base station has a survival detection mechanism, which is: the 5G base station detects the terminal service, when the 5G base station detects no terminal service for a long time, a release process of N2 is initiated, at this time, the AMF sends an Nsmf PDScessonUpdateSM Context to the SMF, under the condition, the resource of the SMF network element is abnormal, at this time, when the AMF accesses the SMF again, because the SMF network element has a transient fault or the gateway resource is insufficient, the Context of the user including the session Context is completely lost, a session update response failure message of the AMF reply protocol data unit is sent, and the AMF replies service rejection to the UE.

As shown in fig. 4, a flow chart of N2 release is provided, which includes the following steps:

step 1a, wireless network Connection Release (R) AN Connection Release;

step 1b, N2 Context Release Request N2 UE Context Release Request;

step 2, N2 Context Release Command N2 UE Context Release Command;

step 3, wireless network Connection releasing (R) AN Connection Release;

step 4, the Context Release of N2 completes N2 UE Context Release Complete;

step 5, PDU conversation establishes updating context Nsmf _ PDUSESION _ UpdateSMContext;

step 6a, modifying the N4 Session Request N4 Session Modification Request;

step 6b, modifying the N4 Session Response N4 Session modification Response;

and 7, updating the context message Nsmf _ PDUSESION _ UpdateSMContext Ack.

Because the context of the user is lost completely including the session context, only the session update response failure message of the protocol data unit can be replied, so that the AMF replies service rejection to the UE, the message reciprocating endless loop between the UE and the AMF of the core network element is caused, the UE still needs to carry out the service request, the terminal still can continuously repeat the service request, the AMF also repeats the service, the SMF refuses the request, and repeats the process for multiple times, the terminal which carries out the service request initiates the active registration until the AMF judges that the signaling is abnormal, then the terminal re-registers to the network and re-initiates the session establishment, and the terminal can normally carry out various services after the session establishment is successful.

In order to solve the above problem, an embodiment of the present invention provides a session service request method to solve the problem that a user cannot access for a long time due to network congestion caused by a round-trip flow and an endless loop of a message between a UE and a network device AMF in the above scenario.

As shown in fig. 5, it is a flowchart of the steps of the session service request method applied to the AMF entity;

step S501, sending a Protocol Data Unit (PDU) session update request message to an SMF, and receiving a PDU session update response message returned by the SMF;

wherein the PDU session service is used for an association between data networks providing the PDU connection service.

The PDU session type may be IPv4, IPv6, IPv4v6, Ethernet or unstructured session type.

Before initiating a service request, the UE needs to perform active registration, and can send the service request to the AMF after the active registration, for example, when the registered UE needs to perform an internet service request, the UE sends the service request to the AMF, and after receiving the service request, the AMF sends a protocol data unit PDU session update request message to the SMF, so that the AMF receives a successful response message sent by the SMF to complete the internet service.

Step S502, when determining that PDU conversation updating request fails, sending a request message for establishing conversation to SMF, requesting to allocate conversation signaling resource and conversation service resource for user terminal UE;

because of the abnormal resource of the SMF network element or the transient failure, when receiving a session update request message of an AMF sending protocol data unit PDU, the SMF replies a failed update response to the AMF, carrying a failure reason code ctx not found, in the prior art, after receiving the failed response message, the AMF can only reply a service request rejection to the UE, compared with the prior art, after receiving the failed response message, the AMF of the present application does not initiate a UE service request rejection procedure to the RAN, but directly sends a session creation request message to the SMF, so that after triggering a scene causing the AMF to reply the service rejection to the UE, a reciprocating message loop is not formed between the E and the RAN, between the RAN and the AMF, between the AMF and the SMF.

The AMF may directly send a session creation request message to the SMF after receiving a response message of SMF failure once, and the AMF may also send a session creation request message to the SMF after receiving a response message of SMF failure for a preset number of times, where the setting of the preset number of times is related to the allocation condition of radio resources, and may be freely set by a person in the art, and details are not described here.

In addition, the session creation request message sent by the AMF to the SMF also carries session signaling resources and session service resources allocated to the UE, and the SMF can assist the UE in performing context registration for the UE by using the session signaling resources and the session service resources.

Step S503, after receiving the response message of successfully creating the session returned by the SMF, sends an initial context setup request message to the RAN entity of the radio access network.

After receiving the response message of successfully creating the session returned by the SMF, the AMF sends an initial context setup request message to an N2 interface of the RAN entity in the radio access network by using the response message of successfully creating the session, so that the RAN replies to the initial context setup response message to complete the session request.

As an optional implementation manner, after sending an initial context establishment request message to a radio access network RAN entity, receiving an initial context establishment success response message returned by the RAN, and resending a PDU session update request message to an SMF;

after the initial context returned by the RAN establishes a successful Response message, indicating that the UE has successfully registered in the base station, the AMF resends a PDU session update request message to the SMF, because of the newly registered initial context, there is no case that the 5G base station detects that the terminal has no service for a long time, and initiates an N2 release process, which causes the context of the user, including the case that the session context is completely lost, at this time, the AMF resends a protocol data unit PDU session update request message to the SMF, the SMF replies an Nsmf _ PDU session _ update smcontext Response successful Response message to the AMF, based on the service tunnel information allocated by the session, so that the session in the service request of the terminal is successfully established, the uplink and downlink services of the session of the UE and the 5G base station are opened, and the subsequent session internet service can be successfully performed.

As an optional implementation manner, the create session request message includes any one or more of the following contents:

1. a user permanent identifier (SUPI), each user in the 5G system should be allocated with a 5G user permanent identifier (SUPI), and configured in the UDM/UDR, the SUPI is only used in the 3GPP system;

UE-selected data network name DNN, where DNN is identical to APN in TS 23.003[19], both identifiers have the same meaning and have the same information, DNN may be used, for example: selecting AMF and UPF for PDU session, or selecting N6 interface for PDU session, or determining strategy applied to PDU session;

2. single network slice selection assistance information S-NSSAI (S), wherein S-NSSAI comprises:

slice/service type (SST) it refers to the expected network slice behavior in terms of functionality and service:

a Slice Differentiator (SD) which is optional information to supplement a slice/service type to distinguish multiple network slices of the same slice/service type.

An S-NSSAI may have a standard value (i.e., such S-NSSAI consists of only SST with a standardized SST value and no SD) or a non-standard value (i.e., such S-NSSAI consists of either SST or SD, or SST with no standardized SST value and no SD. an S-NSSAI with a non-standard value identifies a single network slice within the PLM with which it is associated;

3. the protocol data unit user identification PDU Session ID is used for representing the only protocol data unit;

4. accessing and mobility management function identification AMF ID, wherein the AMF ID is a globally unique FQDN, the AMF can configure one or more GUAMIs, and the GUAMIs with different pointer values are only associated with one AMF name at a given time;

5. the Request Type of the UE is Request Type, wherein the Request Type of the UE comprises service types such as network service Request or session service Request;

6. n1 reference point set N1 SM container, where N1 refers to the reference point between the UE and the AMF;

7. user location information;

8. a channel Type Access Type;

9. radio access Type RAT Type.

As an optional implementation manner, the creating a session response message includes:

creating a result code N2 SM information of successful establishment of the initial context, wherein the N2 SM information comprises PDU session identification;

QoS flow identifiers qfi(s);

QoS configuration QoS profile(s);

the SMF allocates the service Tunnel information CN N3 Tunnel Info for the session, wherein N3 represents the reference point between the (R) AN and the UPF;

single network slice selection assistance information S-NSSAI;

n1 SM message set N1 SM Container.

As an optional implementation manner, the initial context establishment request message includes any one or more of the following:

n2 reference point Request information Request;

security context;

a Mobility Restriction List;

a user terminal aggregates the maximum bit rate UE-AMBR;

the network Service receives the MM NAS Service Accept.

As an optional implementation manner, the initial context setup success response message is an IE N2 SM information, and the IE N2 SM information includes: the base station configures QoS for the service Tunnel information AN Tunnel Info allocated to the session and the received service quality.

Wherein the QoS ID is used to identify QoS flow in the 5G system, user plane traffic with the same QFI within a PDU session, receiving the same traffic forwarding process, the QoS is controlled by SMF, which may be preconfigured, or established through PDU session establishment procedure, or through PDU modification procedure, the SMF provides QoS profile to the AN through AMF at reference point N2, or QoS profile preconfigured in the AN.

For each QoS flow, the QoS profile should include the following parameters: a 5G QoS identifier (5QI), Allocation and Retention Priority (ARP), for each non-GBR QoS flow, may also include: the reflection attribute RQA, for a GBR QoS flow, may further include: guaranteed traffic bit rate (GFBR) and maximum traffic bit rate (MFBR), in case of GBR-only QoS flows, the QoS parameters further include: by controlling, the maximum packet loss rate.

Each QoS profile has a corresponding QoS Flow Identifier (QFI) that is not included in the profile itself.

Because the message carries N2 sm Info, the AMF can immediately initiate an initial context setup request to the RAN to carry PDU session response IE, the IE comprises N2 sm Info received from the SMF in the previous step and carries NAS service request acceptance, the RAN returns an initial context setup response carrying PDU session response IE, the IE comprises a transfer, the AMF sends an Nsmf PDU session update request to the SMF to carry the transfer in the previous response message, the SMF receives a post-processing transfer and replies the Nsmf PDU session update response to the AMF;

the session of the terminal in the service request can be successfully established by using the AN Tunnel Info allocated to the session by the base station and the received QoS configuration QoS.

Fig. 6 is a complete flowchart of a session service request method according to an embodiment of the present invention.

Step 1, UE triggers a service request of an RRC layer;

step 2, RAN sends a service request to AMF by using NGAP message of initial UE;

step 3, AMF sends protocol data unit PDU conversation updating request message to SMF;

step 4, receiving a response message of PDU session update failure returned by the SMF, wherein the response message of the session update failure is 'Context not found';

step 5, AMF sends a session establishment request message for allocating session signaling resources and session service resources to User Equipment (UE) to the SMF;

step 6, the SMF responds to the session creating request message to create a session, and successfully creates a session response message to the AMF;

step 7, after receiving the successful response message of the SMF, the AMF organizes an initial context establishment request message of an N2 interface;

step 8, the RAN replies an initial context establishment success response message, where the initial context establishment success response message carries IE N2 SM information, so that the AMF determines the service tunnel information allocated by the session;

step 9, AMF sends protocol data unit PDU session update request message to SMF according to the service tunnel information in step 8;

step 10, SMF replies Nsmf _ PDUSESION _ UpdateSMContext Response to AMF, which indicates that the session is successfully established.

By using the method provided by the invention, when SMF returns a response message of session modification failure to AMF due to SMF network element resource failure or shortage, AMF directly initiates a session creation request message to SMF for the UE, namely indicates to SMF that the UE needs to create a new PDU session for the UE, because the SMF session creation response message received by AMF carries N2 sm Info, AMF can immediately initiate an initial context creation request to RAN, carries PDU session response IE which contains N2 sm Info received from SMF and carries NAS service request acceptance, RAN returns an initial context creation response and carries PDU session response IE which contains transfer, AMF sends an Nsmf PDU session update request to SMF, SMF receives a post-processing transfer which can reply to AMF for Nsmpdf update request, and the final processing flow of UE can be realized, the method has the advantages of consuming less network resources and solving the problem that the messages between the UE and the AMF are subject to reciprocating flow and endless circulation to cause network congestion and cause long-time access failure of users.

The embodiment of the invention also provides a session service request method which is applied to the SMF entity and comprises the following steps:

receiving PDU conversation updating request information and returning PDU conversation updating response information to AMF.

a user permanent identifier, SUPI;

a data network name DNN selected by the UE;

single network slice selection assistance information S-nssai (S);

a protocol data unit user identification PDU Session ID;

the access and mobility management function identifies the AMF ID;

request Type of UE;

n1 set of reference points N1 SM container;

user location information;

a channel Type Access Type;

radio access Type RAT Type.

and creating a result code N2 SM information of successful establishment of the initial context, wherein the N2 SM information comprises PDU session identification, service quality flow identifiers QFI (S), service quality configuration QoSprofile (S), service Tunnel information CN N3 Tunnel Info allocated by the SMF for the session, single network slice selection auxiliary information S-NSSAI, and a N1 reference point set N1 SM Container.

n2 reference point Request information Request;

security context;

a Mobility Restriction List;

a user terminal aggregates the maximum bit rate UE-AMBR;

MM NAS Service Accept MM NAS Service Accept.

Optionally, the initial context setup success response message is an IE N2 SM information, where the IE N2 SM information includes: the base station configures QoS for the service Tunnel information AN Tunnel Info allocated to the session and the received service quality.

The session service request method applied to the SMF entity provided in the embodiment of the present invention and the session service request method applied to the AMF entity provided in the above embodiment of the present invention belong to the same inventive concept, and various embodiments applied to the session service request method in the above embodiment can be applied to the session service request method applied to the SMF entity in the embodiment and are not repeated here.

An embodiment of the present invention provides an AMF entity apparatus, as shown in fig. 7, including one or more processors (CPU) 701 (e.g., one or more processors) and a memory 702, one or more storage media 703 (e.g., one or more mass storage devices) for storing an application 704 or data 706. Memory 702 and storage medium 703 may be, among other things, transient storage or persistent storage. The program stored on the storage medium 703 may include one or more modules (not shown). Further, the processor 701 may be configured to communicate with the storage medium 703 to execute a series of instruction operations in the storage medium 703 on the device 700.

The apparatus 700 may also include one or more power supplies 710, one or more wired or wireless network interfaces 707, one or more input-output interfaces 708, and/or one or more operating systems 705, such as Windows Server, Mac OS X, Unix, Linux, FreeBSD, etc.

after receiving the initial context establishment success response message returned by the RAN, retransmitting a PDU session update request message to the SMF;

and receiving a PDU session update response message returned by the SMF.

a user permanent identifier, SUPI;

a data network name DNN selected by the UE;

single network slice selection assistance information S-nssai (S);

a protocol data unit user identification PDU Session ID;

the access and mobility management function identifies the AMF ID;

request Type of UE;

n1 set of reference points N1 SM container;

user location information;

a channel Type Access Type;

radio access Type RAT Type.

Optionally, the creating a session response message includes:

n2 reference point Request information Request;

security context;

a Mobility Restriction List;

a user terminal aggregates the maximum bit rate UE-AMBR;

the network Service receives the MM NAS Service Accept.

The AMF entity device provided in the embodiment of the present invention and the session service request method applied to the AMF entity provided in the above embodiment of the present invention belong to the same inventive concept, and various implementation manners applied to the session service request method in the above embodiment may be applied to the AMF entity device in the present embodiment for implementation, and are not repeated here.

An embodiment of the present invention provides an SMF entity apparatus, as shown in fig. 8, which includes one or more processors (CPU) 801 (e.g., one or more processors) and a memory 802, and one or more storage media 803 (e.g., one or more mass storage devices) for storing an application 804 or data 806. Memory 802 and storage medium 803 may be, among other things, transient storage or persistent storage. The program stored on the storage medium 803 may include one or more modules (not shown). Still further, the processor 801 may be configured to communicate with the storage medium 803 to execute a series of instruction operations in the storage medium 803 on the device 800.

The apparatus 800 may also include one or more power supplies 810, one or more wired or wireless network interfaces 807, one or more input-output interfaces 808, and/or one or more operating systems 805, such as Windows Server, Mac OS X, Unix, Linux, FreeBSD, etc.

a user permanent identifier, SUPI;

a data network name DNN selected by the UE;

single network slice selection assistance information S-nssai (S);

a protocol data unit user identification PDU Session ID;

the access and mobility management function identifies the AMF ID;

request Type of UE;

n1 set of reference points N1 SM container;

user location information;

a channel Type Access Type;

radio access Type RAT Type.

n2 reference point Request information Request;

security context;

a Mobility Restriction List;

a user terminal aggregates the maximum bit rate UE-AMBR;

the network Service receives the MM NAS Service Accept.

The SMF entity device provided in the embodiment of the present invention and the session service request method applied to the AMF entity provided in the above embodiment of the present invention belong to the same inventive concept, and various implementation manners applied to the session service request method in the above embodiment may be applied to the SMF entity device in the present embodiment for implementation, and are not repeated here.

An embodiment of the present invention provides a session service request apparatus, as shown in fig. 9, the apparatus includes the following units:

a request receiving unit 901, configured to receive a protocol data unit PDU session update request message sent by an AMF;

a request response unit 902, configured to perform a session update procedure and send a PDU session update response message to the AMF;

an initial context request unit 903, configured to receive a session creation request message sent by the AMF when determining that the PDU session update request fails, and allocate a session signaling resource and a session service resource to the UE;

Optionally, the initial context requesting unit 903 is configured to, after sending the initial context setup request message to the RAN entity of the radio access network, further include:

receiving an initial context establishment success response message returned by the RAN, and retransmitting a PDU session update request message to the SMF;

and receiving a PDU session update response message returned by the SMF.

a user permanent identifier, SUPI;

a data network name DNN selected by the UE;

single network slice selection assistance information S-nssai (S);

a protocol data unit user identification PDU Session ID;

the access and mobility management function identifies the AMF ID;

request Type of UE;

n1 set of reference points N1 SM container;

user location information;

a channel Type Access Type;

radio access Type RAT Type.

Optionally, the creating a session response message includes:

n2 reference point Request information Request;

security context;

a Mobility Restriction List;

a user terminal aggregates the maximum bit rate UE-AMBR;

the network Service receives the MM NAS Service Accept.

The session service request device provided in the embodiment of the present invention and the session service request method applied to the AMF entity provided in the above embodiment of the present invention belong to the same inventive concept, and various embodiments applied to the session service request method in the above embodiment may be applied to the session service request device in the present embodiment for implementation, and are not repeated here.

An embodiment of the present invention provides a session service request apparatus, as shown in fig. 10, the apparatus includes the following units:

a request receiving unit 1001, configured to receive a protocol data unit PDU session update request message sent by an AMF;

a request response unit 1002, configured to perform a session update procedure and send a PDU session update response message to the AMF;

an initial context requesting unit 1003, configured to receive a session creation request message sent by the AMF when determining that the PDU session update request fails, and allocate a session signaling resource and a session service resource to the UE;

Optionally, the request receiving unit 1001 is configured to, after the AMF sends the initial context request message to the RAN, further include:

a user permanent identifier, SUPI;

a data network name DNN selected by the UE;

single network slice selection assistance information S-nssai (S);

a protocol data unit user identification PDU Session ID;

the access and mobility management function identifies the AMF ID;

request Type of UE;

n1 set of reference points N1 SM container;

user location information;

a channel Type Access Type;

radio access Type RAT Type.

n2 reference point Request information Request;

security context;

a Mobility Restriction List;

a user terminal aggregates the maximum bit rate UE-AMBR;

the network Service receives the MM NAS Service Accept.

An embodiment of the present invention provides a computer storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements any one of the session service request methods provided in the above embodiments.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

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

Claims

1. A session service request method is applied to an access and mobility management function (AMF) entity, and is characterized by comprising the following steps:

sending a Protocol Data Unit (PDU) session update request message to a Session Management Function (SMF), and receiving a PDU session update response message returned by the SMF;

2. The method of claim 1, wherein after sending the initial context setup request message to the radio access network RAN entity, further comprising:

and receiving a PDU session update response message returned by the SMF.

3. The method according to claim 1, wherein the create session request message includes any one or more of the following:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

4. The method of claim 1, wherein creating the session response message comprises:

and creating a result code of successful initial context establishment, wherein the result code comprises PDU session identification, a service quality flow identifier, service quality configuration information, traffic tunnel information distributed by the SMF for the session, single network slice selection auxiliary information and an N1 reference point set.

5. The method of claim 1, wherein the initial context setup request message comprises any one or more of:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

6. The method of claim 2, wherein the initial context setup success response message is N2 reference point information, and wherein the N2 reference point information comprises: and the base station distributes the service tunnel information and the received service quality configuration information for the session.

7. A session service request method is applied to a Session Management Function (SMF) entity, and is characterized by comprising the following steps:

8. The method of claim 7, wherein after sending the initial context request message to the RAN, the AMF further comprises:

9. The method according to claim 7, wherein the create session request message carries any one or more of the following:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

10. The method according to claim 7, wherein the create session response message includes any one or more of the following:

11. The method of claim 7, wherein the initial context setup request message comprises any one or more of:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

12. The method of claim 8, wherein the initial context setup success response message is N2 reference point information, and wherein the N2 reference point information comprises: the base station distributes the service tunnel information and the received service quality configuration information for the session.

13. An AMF entity apparatus, characterized in that the apparatus comprises:

a memory to store instructions;

14. The apparatus of claim 13, wherein after the processor sends an initial context setup request message to a Radio Access Network (RAN) entity, the apparatus further comprises:

and receiving a PDU session update response message returned by the SMF.

15. The device of claim 13, wherein the create session request message includes any one or more of the following:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

16. The apparatus of claim 13, wherein the create session response message comprises:

17. The apparatus of claim 13, wherein the initial context setup request message comprises any one or more of:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

18. The apparatus of claim 14, wherein the initial context setup success response message is N2 reference point information, and wherein the N2 reference point information comprises: the base station distributes the service tunnel information and the received service quality configuration information for the session.

19. An SMF entity apparatus, characterized in that the apparatus comprises:

a memory to store instructions;

20. The apparatus of claim 19, wherein the processor, after the AMF sends an initial context request message to the RAN, further comprises:

21. The device according to claim 19, wherein the create session request message carries any one or more of the following:

a user permanent identifier;

a data network name selected by the UE;

single network slice selection assistance information;

a protocol data unit user identity;

access and mobility management function identification;

a request type of the UE;

a set of N1 reference points;

user positioning information;

a channel type;

a radio access type.

22. The device of claim 19, wherein the create session response message includes any one or more of the following:

23. The apparatus of claim 19, wherein the initial context setup request message comprises any one or more of:

n2 reference point request information;

a security context;

a list of movement restrictions;

aggregating the maximum bit rate by the user terminal;

the network service receives the information.

24. The apparatus of claim 20, wherein the initial context setup success response message is N2 reference point information, and wherein the N2 reference point information comprises: the base station distributes the service tunnel information and the received service quality configuration information for the session.

25. A session service request apparatus, characterized in that the apparatus comprises the following units:

a session update unit, configured to send a protocol data unit PDU session update request message to an SMF, and receive a PDU session update response message returned by the SMF;

a session creating unit, configured to send a session creating request message to the SMF when it is determined that the PDU session update request fails, and request to allocate session signaling resources and session service resources to the UE;

an initial context request unit, configured to send an initial context setup request message to a radio access network RAN entity after receiving a session creation success response message returned by the SMF.

26. A session service request apparatus, characterized in that the apparatus comprises the following units:

27. A computer storage medium on which a computer program is stored, the computer program implementing the method according to any of claims 1-6 when executed by a processor or the computer program implementing the method according to any of claims 7-12 when executed by a processor.