CN109413640B

CN109413640B - Session information query method, network element and computer storage medium

Info

Publication number: CN109413640B
Application number: CN201711003254.9A
Authority: CN
Inventors: 陈旭; 陈炜
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2017-08-18
Filing date: 2017-10-24
Publication date: 2021-10-08
Anticipated expiration: 2037-10-24
Also published as: CN109413640A

Abstract

The embodiment of the invention provides a session information query method, a network element and a computer storage medium. The session information query method is applied to an open function network element and comprises the following steps: receiving an application service request carrying a network protocol IP address of User Equipment (UE); inquiring identification information of a session management function network element for performing session management on the UE according to the IP address of the UE; based on the identification information of the session management function network element, sending a query request carrying the IP address of the UE to the corresponding session management function network element; receiving session information returned by the session management function network element based on the query request, wherein the session information at least comprises: and the UE controls the identification information of the network element.

Description

Session information query method, network element and computer storage medium

Technical Field

The present invention relates to the field of mobile communications technologies, and in particular, to a session information query method, a network element, and a computer storage medium.

Background

Policy and Charging Control (PCC) of 4G networks requires that Gx interface sessions and Rx interface sessions of the same user are bound on the same Policy and Charging Rules Function (PCRF). When a plurality of PCRF entities are deployed, a Routing Agent node (DRA) is required to implement session binding, and a binding relationship between a user code number, an Internet Protocol (IP) address and a PCRF address is stored to form session binding information.

Similar to the session binding requirement of the Gx/Rx interface of the 4G core Network, the signaling of the N7 and N5 (or Rx) interfaces of the Public Data Network (PDN) session related interface of the same user in the 5G core Network needs to be addressed to the same Policy Control Function (PCF).

The prior art has two implementation schemes:

the existing scheme I is as follows: introducing a new Network Function (NF) entity for realizing information binding, query and routing;

the existing scheme is as follows: storing the session binding information in a database (SDSF) separately for storing the binding information; the generation of binding information and the querying are performed separately.

In both existing methods, session binding relationships of all UEs in a network are separately stored in a new functional entity or a data storage functional entity, which has the following problems:

data consistency: storing the session binding information by adopting an independent database, and ensuring the consistency of data in real time, namely the session binding relation of the database is completely consistent with the actual binding relation in the network;

additional signaling overhead and signaling processing: except for the query signaling of the session binding information, the database needs to be accessed when the session is created and deleted, and additional signaling processing overhead is caused;

storing and inquiring session binding data in a roaming scene: for roaming scenarios, it is further necessary to analyze whether the session binding information is stored in the home network or the visited network, or both.

Disclosure of Invention

In view of the above, embodiments of the present invention are directed to a session information query method, an NEF, and a computer storage medium, which at least partially solve the above problem of complex PCF addressing operation and/or high overhead.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

in a first aspect, an embodiment of the present invention provides a session information query method, applied to an open function network element, including:

receiving an application service request carrying a network protocol IP address of User Equipment (UE);

inquiring identification information of a session management function network element for performing session management on the UE according to the IP address of the UE;

based on the identification information of the session management function network element, sending a query request carrying the IP address of the UE to the corresponding session management function network element;

receiving session information returned by the session management function network element based on the query request, wherein the session information at least comprises: and the UE controls the identification information of the network element.

In a second aspect, a method for querying session information is provided, which is applied to a network element with a session management function, and includes:

receiving a query request of a network open function network element carrying an IP address of User Equipment (UE), wherein the query request is as follows: the network element with the receiving network open function sends the application service request carrying the IP address of the UE when receiving the application service request;

inquiring session information generated in the UE session establishment process based on an inquiry request; the session information at least includes: identification information of a policy control network element of the UE;

and sending the session information to the receiving network open function network element.

In a third aspect, an embodiment of the present invention provides a session information query method, including:

an open function network element receives an application service request, wherein the application service request carries a network protocol IP address of User Equipment (UE);

the open function network element queries a mapping relation according to the IP address of the UE to obtain identification information of a session management function network element corresponding to the IP address of the UE, wherein the mapping relation is as follows: the corresponding relation between the IP address of the UE and the identification information of the session management function network element of the UE;

the network open function sends a query request carrying the IP address of the UE to a session management function network element according to the identification information of the session management function network element;

the session management function network element queries session information generated in a session process of the UE based on the IP address of the UE, wherein the session information at least comprises: identification information of a policy control network element of the UE;

and the session management function network element sends the session information to the open function network element.

In a fourth aspect, an open function network element is provided, including:

a first receiving unit, configured to receive an application service request carrying a network protocol IP address of a user equipment UE;

a first query unit, configured to query, according to the IP address of the UE, identification information of a session management function network element that performs session management on the UE;

a first sending unit, configured to send, based on the identification information of the session management function network element, an inquiry request carrying the IP address of the UE to a corresponding session management function network element;

a second receiving unit, further configured to receive session information returned by the session management function network element based on the query request, where the session information at least includes: and the identification information of the strategy control corresponding to the UE.

In a fifth aspect, there is provided a session management function network element, including:

a third receiving unit, configured to receive an inquiry request that a network element with an open network function carries an IP address of a user equipment UE, where the inquiry request is: the network element with the receiving network open function sends the application service request carrying the IP address of the UE when receiving the application service request;

a second querying unit, configured to query, based on the query request, session information generated in a session establishment procedure of the UE, where the session information at least includes: identification information of policy control corresponding to the UE;

and a second sending unit, configured to send the session information to the network element with network open function.

In a sixth aspect, there is provided a network element, comprising: a memory, a processor, a transceiver, and a computer program stored on the memory and executed by the processor;

the processor is connected with the memory and used for controlling the information storage of the memory and the information transceiving of the transceiver by executing the computer program and realizing the session information inquiry method provided by one or more of the schemes.

In a seventh aspect, a computer storage medium having a computer program stored thereon is provided; the computer program can be executed to implement the session information query method provided by one or more of the above-mentioned schemes.

The embodiment of the invention provides a session information query method, a network element and a computer storage medium, wherein in the process of modifying the response of an AF (Application Function, AF) request, after an open Function network element receives an Application service (AF) request, the open Function network element queries a session management Function network element of UE (user equipment) by using an IP address of the UE carried in the Application service (AF) request, and an SMF determines identification information of a policy control network element corresponding to the UE by using the IP address of the UE and identification information of a PCF (subscriber identity module) stored in session information generated during attachment of the UE, so that the addressing of the policy control network element is completed. And responding to the AF request by using the identification information of the addressed strategy control network element. The technical scheme provided by the embodiment of the invention has the following beneficial effects:

on the first hand, a special network function entity or a database is not set, and the special binding is carried out to generate the session binding information, but the network elements such as an open function network element, a session management function network element and the like are multiplexed, so that the network elements used in the addressing process of the policy control network element are simplified, and the network structure is simplified;

in the second aspect, a binding process of session binding information is not required, so that the operation before the addressing of the policy control network element is simplified;

in the third aspect, there is no special binding flow, the session binding information is not stored in a specific network element or database, and the IP address of the UE and the identification information of the policy control network element are both stored in the session information in the SMF, and if the IP address of the UE is changed, the session information corresponding to the UE is necessarily changed again, thereby solving the problem of data inconsistency in the prior art.

In the fourth aspect, for the UE roaming scenario, there is no decision problem that the session binding information is stored in the database of the home location or in the database of the visited location, and the problem that the addressing of the policy control network element is abnormal due to roaming.

Drawings

Fig. 1 is a schematic flowchart of a first session information query method according to an embodiment of the present invention;

fig. 2 is a schematic flowchart of a second session information query method according to an embodiment of the present invention;

fig. 3 is a flowchart illustrating a third session information query method according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a first open function network element according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a network system according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a session management function network element according to an embodiment of the present invention

Fig. 7 is a schematic structural diagram of a second open function network element according to an embodiment of the present invention;

fig. 8 is a flowchart illustrating a fourth session information query method according to an embodiment of the present invention;

fig. 9 is a flowchart illustrating a fifth session information query method according to an embodiment of the present invention;

fig. 10 is a schematic diagram illustrating a process of establishing a mapping relationship according to an embodiment of the present invention;

fig. 11 is a schematic diagram illustrating another mapping relationship establishment procedure according to an embodiment of the present invention.

Detailed Description

The technical solution of the present invention is further described in detail with reference to the drawings and the specific embodiments of the specification.

In the embodiment of the present invention, the network element with the network open function may be referred to as an open function network element or NEF, for short.

The embodiment provides a session information query method, which is applied to an open function network element. The open Function Network element may provide an open Network or a Service Capability for an open Function Network Element (NEF), a Service Capability open Function Network element (SCEF), and the like. As shown in fig. 1, the method includes:

step S110: receiving an AF request carrying an IP address of UE;

step S120: inquiring identification information of a session management function network element for performing session management on the UE according to the IP address of the UE;

step S130: based on the identification information of the session management function network element, sending a query request carrying the IP address of the UE to the corresponding session management function network element;

step S140: and receiving session information returned by the session management function network element based on the query request, wherein the session information at least comprises identification information of a policy control network element of the UE.

The Session Management Function network element may be a Session Management Function network element (SMF) or a Policy and Charging Enforcement Function network element (PCEF). The Policy control network element may be a PCF or a Policy and Charging Rule Function (PCRF) network element.

For example, the NEF provides a unified standard interface for connecting the AF to the communication network, and a Front End (NEF Front End, NEF FE) of the NEF receives information transmitted by the AF, and provides a database to store the information received by the NEF FE, and encapsulates the information into a specified unified format of the communication network for transmission to the communication network. In this embodiment, the NEF may perform network isolation and security isolation with the application server, so as to ensure the security, reliability, and stability of communication in the communication network in communication operation.

For example, the SMF may be used to manage session procedures such as session connection and session release of the UE, and the SMF may also be used to allocate and manage an IP address of the UE.

In this embodiment, the IP address of the UE may be divided into an IPv4 address and an IPv6 address according to the length of the IP address of the address. The IP address of the UE is classified according to its usable range, and may be classified into a public network IP address unique to the whole network and a private network IP address recognizable only in a certain IP domain. If the current allocated IP address is a private network IP address, the SMF also needs the IP domain where the private network IP address allocated by the UE is located, so that the private network IP address of the UE needs to be managed, and the IP domain where the private network IP address of the UE is located needs to be managed.

For example, the PCF may be used to provide a framework for supporting a unified policy to manage network behavior, policy rules to control plane functions to enforce policies, and Front End (PCF Front End, PCF FE) to access subscription information related decisions in a unified data repository.

For example, the AF is an abbreviation of a functional entity providing an application service, and may be one of the senders in fig. 1, and may be an application server providing a specific application service. In some embodiments, the AF request may also be a request from an AF forwarded by another network element.

In some embodiments, the open function network element, the session management function network element, the policy control network element, and the like are related to network elements that can be set in a communication network provided by a communication operator. The open function network element may be configured to enable an AF of a service provider to connect into a communication network. In this embodiment, the AF request may be: the application service requests the entity or the application server, or the application service platform to send the request related to the specific service. The AF request may be various service requests related to the application service sent by the application server of the third-party application. The service request may carry an IP address of the UE, and the IP address of the UE may be an IP address allocated to the UE when the communication network is attached to the network. In this embodiment, the IP address of the UE carried by the AF request may be an IP address of one UE, or may be IP addresses of multiple UEs. In step S120, the identification information of the session management function network element corresponding to the IP address of each UE is queried. The obtained session management function network elements of different UEs may be the same or different. If the session management function network elements of different UEs are different, the NEF may query identification information, such as addresses of session management network elements respectively corresponding to different UEs. And then based on identification information such as addresses of the session management function network elements of different UEs, sending a query request to the corresponding session management function network element to query the session information of the corresponding UE.

In this embodiment, in 5G, the AF and the open function network element perform interaction of various information, for example, the AF request, through an interface (N5 or Rx). For example, the session management function network element and the policy control network element communicate various information via an interface (N7). The session management function network element and the policy control network element may perform information interaction of session flows, such as establishment and/or release of a Protocol Data Unit (PDU) session, through N7. In a 5G network, a session management function network element is responsible for allocating an IP address to a UE (i.e. allocating the IP address of the UE), there is a corresponding relationship between an identifier of the UE (international mobile subscriber identity IMSI) and the IP address of the UE, and in a PDU session establishment process, the session management function network element may obtain session binding information of a specific PDU session, and store the session binding information in a context of the UE to form the session information.

In order to ensure that the IP address of the UE is not repeated, IP address pools divided for different session management function network elements are planned in advance and are not overlapped, so that the session management function network element for providing session management for the UE can be found through an IP address field to which the IP address of the UE belongs, and addressing to the policy control network element can be realized by directly inquiring session binding information on the session management function network element.

After receiving the IP address, the open function network element queries the IP address of the UE and identification information of a session management function network element that manages a session of the UE, where the identification information of the session management function network element may be the IP address of the session management function network element or an identification (Identity, ID) of the session management function network element.

The session management function network element is used for performing session management on the managed UE and allocating and managing an IP address to the UE. The UE initiates a PDN session when attaching to the network after starting up, the session management function network element records some information in the PDN session process to form a session record, and the session record records identification information of a policy control network element for performing policy control on the UE.

The identification information of the policy control network element may be: the IP address of the policy control network element or various information such as the ID of the policy control network element that can uniquely identify the policy control network element in the communication network.

Therefore, after determining the session management function network element corresponding to the IP address of the UE in this embodiment, sending a query request to the corresponding session management function network element; in this way, after receiving the IP address of the UE, the session management function network element may locally query the session record, so as to obtain identification information of a policy control network element performing policy control on the UE.

And sending the strategy control network element as response information of the query request to the open function network element, so that the open function network element receives the identification information of the strategy control network element corresponding to the IP address of the UE carried in the AF request.

In some embodiments, the session information further comprises: at least one of a communication identity of the UE, a wireless communication type of the UE, and a QoS of the UE communication.

The identification information of the session management function includes: at least one of a name, an Identification (ID) and an IP address of the session management function;

the session information includes identification information of a policy control network element corresponding to the UE, and the identification information of the policy control network element includes: and at least one of the name, the ID and the IP address of the policy control network element.

In some embodiments, the method further comprises:

and the open function network element sends the request content in the AF request to the strategy control network element corresponding to the identification information of the strategy control network element. And the strategy control network element receives the request content, responds to the AF request of the AF, and performs transmission control and/or charging control and the like on the applied application service.

In this embodiment, the Network element with an open function and the Network element with a session management function only need to belong to the same Public Land Mobile Network (PLMN), or belong to the same communication Network operator.

When the UE roams, the method of providing the session information query method may be different according to the different manner of providing the roaming service for the UE.

In some embodiments, when the roaming service is provided in a Local breakout (Local breakout) manner, session management is performed by a visited session management function network element (vSMF) of a visited network of the UE, policy control is performed by a visited policy control network element (vPCF), and an access service requested by an AF is provided by a visited open function network element (vNEF). Therefore, in this roaming method, the vNEF, vSMF, and vPCF in the visited network of the visited site where the UE is located execute the above steps S110 to S130.

In other embodiments, when the roaming service is provided by using a Home routing (Home Routed) manner, the policy control network element addressing operation is provided by a Home session management function network element (hSMF), a Home policy control network element (hPCF), and a Home open function network element (hNEF) of the UE.

Of course, NEF here may be replaced by SCEF; the PCF can be replaced by a PCRF; the session management function network element may be replaced by a PCEF.

In this way, the session information query method provided in this embodiment also solves the problems of complex session binding information storage and abnormal addressing of the policy control network element under the roaming condition of the UE.

Therefore, in this embodiment, the provided session information query method has the following characteristics:

on the first hand, the existing various network elements are used for addressing the strategy control network element, the strategy control network element can be addressed without introducing a new network element entity, and a special network element or a database is not required to be introduced for storing the IP address of the UE and the information of the identification of the strategy control network element, so that the introduction of the new network element is avoided, and the further complication of the network is avoided.

In a second aspect, in this embodiment, allocated IP addresses of the UE that are attached to the network may be different when the UE is powered on at different times, and a dedicated binding procedure is not needed compared to the existing method that uses a dedicated database to perform relatively static storage and binding, and a problem of data inconsistency caused by dynamic allocation of the IP address of the UE can be avoided.

In the third aspect, when the policy control network element is addressed, a dedicated query flow is not required to be configured, and only by determining the session management function network element for session management of the UE when an AF request is received and returning the identification information of the corresponding policy control network element from the session result recorded in the session management function network element, the addressing of the policy control network element is simply and conveniently completed only by slightly changing the response flow of the AF request, and the method is strong in compatibility with the prior art and simple and convenient to implement.

In a fourth aspect, the above method is adopted to address the policy control network element, and the problem that the policy control network element is difficult to address when the UE roams is also solved.

Optionally, the method further comprises:

pre-configuring a mapping relation between identification information of a session management function network element and an IP address of UE; for example, the IP address field corresponding to the session management function network element is planned in advance. In this embodiment, the mapping relationship may be a mapping relationship of an IP address field corresponding to a session management function network element. The assignable and managed IP addresses of one of said session management function network elements are continuously distributed, and these continuously distributed IP addresses form an IP address field. The mapping relationship may be a correspondence relationship between identification information of the session management function network element and IP addresses at both ends of the IP address field.

In some further embodiments, if the IP addresses of the UEs assignable by the session management function network element are not continuously distributed, the mapping relationship may be a one-to-one mapping relationship between the identification information of the session management function network element and the IP addresses of the UEs assignable and managed by the session management function network element. For example, the mapping relationship may be a mapping relationship table, where at least identification information of the session management function network element and an IP address of each UE that can be allocated and managed by the session management function network element are stored in the table. In this way, in step S120, the session management function network element of the UE allocated by the IP address of the UE can be determined through one-by-one matching of the IP addresses of the UEs.

The step S120 may include:

and according to the IP address of the UE, locally inquiring the mapping relation to obtain the identification information of the session management function network element.

The step S120 may include: and judging the IP address field of the IP address of the UE, and determining the corresponding session management function network element of the UE according to the identification information of the session management function network element corresponding to the IP address field of the IP address of the UE.

The step S120 may include: and matching the IP address of the UE with the IP address field, and judging the front-back relation of the addresses so as to determine the IP address field of the IP address of the UE.

In this embodiment, the open function network element stores in advance a corresponding relationship between each session management function network element and an IP address of a UE that can be allocated to the session management function network element, so that when an AF request is received, the NEF can locally query a mapping relationship to obtain identification information of the session management function network element.

In some embodiments, as shown in fig. 2, the step S120 may further include:

step S121: sending a discovery request carrying the IP address of the UE to a network discovery network element (NRF), wherein the NRF is pre-configured with a mapping relation between identification information of a session management function network element and the IP address of the UE;

step S122: and receiving the identification information of the session management function network element returned by the NRF, wherein the identification information of the session management function network element is determined by inquiring the mapping relation by taking the IP address of the UE as an inquiry basis.

The NRF is a short for network discovery function entity and may be used to provide a service discovery function. In this embodiment, the NRF is multiplexed to store the mapping relationship between the identification information of the session management function network element and the IP address of the UE. Also in this embodiment, the mapping relationship may be a mapping relationship between the identification information of the session management function network element and the IP address field.

In this embodiment, when the mapping relationship is not stored in the open function network element itself, a discovery request is directly sent to the NRF, where the discovery request carries an IP address of the UE. And the NRF takes the IP address of the UE as a query basis, and returns the identification information of the corresponding session management function network element to the open function network element after querying the mapping relation. In this way, in step S120, the open-function network element queries the identification information of the session management function network element corresponding to the IP address of the UE through going to the NRF.

The aforementioned mapping relationship between the identification information of the session management function network element of the UE and the IP address of the UE is stored in the NEF in advance or stored in the NRF in advance. The pre-storing here may include:

pre-configured in NEF or NRF, for example, receiving an instruction of a manager through a human-computer interaction interface or the like, and writing the instruction into the mapping relationship; for another example, a management interface receives a write command from a management system, and writes the mapping relationship.

In some further embodiments, the NEF and the NRF generate the mapping relationship by themselves, for example, obtain an IP address managed by the SMF, and automatically establish a mapping relationship between the identification information of the SMF and the IP address.

For example, for the NEF, the NEF first sends a request to the NRF to query the address of the SMF, and after querying from the NRF to the address of the SMF, sends a subscription request to the SMF. After receiving the subscription request, the SMF sends the IP address of the UE managed by the SMF to the NEF, and after receiving the IP addresses, the NEF automatically establishes the mapping relationship, so as to implement the automatic establishment of the mapping relationship in the NEF, which specifically includes:

sending a query request of the address of the session management function network element to the network discovery function network element; the address returned here may be a list of addresses of one or more session management function network elements returned in the form of a list; in some embodiments, the NRF may return the addresses of all SMFs to the NEF, or may return the addresses of SMFs within a specified geographic area;

sending a subscription request to the session management function network element based on the address of the session management function network element; the subscription request is used for triggering the session management function network element to send the IP address set or the IP address segment to the open function network element when the IP address set or the IP address segment planned and managed by the session management function network element is changed or the IP address set or the IP address segment managed by the session management function unit is triggered to be changed; the set of IP addresses includes: an IP address of one or more assignable UEs; the IP address field may include: a segment of consecutively assigned IP addresses that may be assigned to the UE.

Receiving an IP address set or an IP address field returned by the session management network element based on the subscription request;

creating or updating a mapping relation between identification information of a session management function network element and an IP address of the UE according to the IP address set or the IP address field and the identification of the session management network element;

the step S120 may include: and inquiring the mapping relation according to the IP address of the UE.

For NRF, the NRF may acquire the IP address of the UE managed by the SMF in various manners, but in this embodiment, to simplify the flow, the NRF may automatically establish the mapping relationship in the following manner, including:

the network discovery function network element receives a service registration request of a session management function network element; wherein, the service registration request carries an IP address set or an IP address field managed by the session management network element;

and the network discovery function network element creates or updates the mapping relation between the identification information of the session management function network element and the IP address of the UE according to the IP address set or the IP address field and the identification information of the session management function network element.

The creating mapping relationship may be: and initially establishing a mapping relation between the identification information of the session management function network element and the IP address of the UE. The updating the mapping relationship may include: and updating the mapping relation which is already created.

In general, the service registration request is a request for registering a service that can be provided by the SMF to the NRF, and the service registration request carries a service identifier, such as a service name, of the service that can be provided by the SMF, so that the NRF can register the service conveniently. In this embodiment, the service registration request carries an IP address managed by an SMF, which facilitates the NRF to establish the mapping relationship.

The mapping relationship may include multiple types, and specifically may be the following mapping relationship between the identification information of the session management function network element and the IP address of the UE, including at least one of the following:

mapping relation between the identification information of the session management function network element and the public network IP address of the UE;

the mapping relation between the identification information of the session management function network element and the private network IP address of the UE and the domain identification of the IP domain where the private network IP address is located;

mapping relation between the identification information of the session management function network element and the IPv4 address of the UE;

and mapping relation between the identification information of the session management function network element and the IPv6 address of the UE.

The public network IP address is an IP address unique to the whole network, and other devices can uniquely locate the UE after taking the IP address.

Private network IP addresses in different IP domains may be duplicated, but a combination of a domain identifier of an IP domain and a private network IP address is unique throughout the network, so in this embodiment, in order to accurately correspond to a correspondence between identifier information of a session management function network element and an IP address of a UE, if an IP address acquired by the UE is a private network IP address, the mapping relationship is: and the identification information of the session management function network element corresponds to the private network IP address of the UE and the domain identification of the IP domain where the private network IP address is located.

In some embodiments, the domain identifier of the IP domain may be a public network IP address corresponding to a private network domain where the private network IP address is located. For example, the public network and the private network are isolated by a device such as a switch or a router, and the domain identifier of the IP domain may be a public network IP address bound by the switch or the router.

When the UE communicates using the private IP Address, various Network elements such as the switch and the router need to perform Network Address Translation (NAT). For example, when the UE transmits a packet to another device using a private IP address, after receiving the packet transmitted by the UE, the device such as a switch or a router needs to convert the source IP address in the packet from the private IP address of the UE to a public IP address. If a data packet sent to a private network by an external network is received, a target IP address in the data packet needs to be converted from a public network IP address to a private network IP address and then forwarded out from a port of the private network, so that the correct UE can be ensured to receive the data packet.

The domain identification of the IP domain may also be the name, number of the NAT device mapped by the private and public network addresses or the public network IP address segment used on the NAT device.

In this case, the step S120 may specifically include at least one of the following steps:

inquiring identification information of a session management function network element for performing session management on the UE according to the public network IP address of the UE;

inquiring identification information of a session management function network element for performing session management on the UE according to the private network IP address of the UE and a domain identification corresponding to an IP domain where the private network IP address is located;

according to the IPv4 address of the UE, inquiring identification information of a session management function network element for carrying out session management on the UE;

and inquiring identification information of a session management function network element for performing session management on the UE according to the IPv6 address of the UE.

If the UE is only allocated a private network IP address, when querying a session management function network element of the UE, the UE needs to query based on the private network IP address of the UE and the domain identifier of the IP domain to which the private network IP address belongs.

When the query request carrying the IP address of the UE is sent to the session management function network element in step S130, the following cases may be considered:

if a session management function network element only manages session information of UEs in an IP domain, the step S130 may include at least one of the following steps:

based on the identification information of the session management function network element, sending a query request carrying the public network IP address of the UE to the corresponding session management function network element;

based on the identification information of the session management function network element, sending a query request carrying the private network IP address of the UE to the corresponding session management function network element;

based on the identification information of the session management function network element, sending a query request carrying the IPv4 address of the UE to the corresponding session management function network element;

and sending a query request carrying the IPv6 address of the UE to the corresponding session management function network element based on the identification information of the session management function network element.

If a session management function network element manages session information of UEs in multiple IP domains, the step S130 may include at least one of the following steps:

based on the identification information of the session management function network element, sending an inquiry request carrying the private network IP address of the UE and the domain identification of the IP domain where the private network IP address is located to the corresponding session management function network element;

In some embodiments, the step S130 may include:

and receiving the identification information of the policy control network element, which is obtained by the session management function network element through inquiring session information, wherein the session information is a session record generated when the UE is attached to a network.

The UE is attached to a network after being started, the session management function network element allocates an IP address of the UE to the UE in the process that the UE requests to attach to the network, selects a corresponding strategy control network element to establish a PDU session corresponding to the UE, and records the IP address of the UE in the session process, identification information of the corresponding strategy control network element and the like.

In this embodiment, the session information may be a context of a PDU session. Typically, the PDU session is released after the UE is powered off.

In summary, the present embodiment provides a session information query method, which adds session management function network element determination and session management function network element query session information provision policy control network element identification information in a response flow of an AF request by using an existing network element, does not need to generate session binding information specially, does not need to add a new network element, and does not have the problem of inconsistency caused by dynamic allocation of an IP address of a UE, and has the characteristics of few operation steps, simple implementation, and strong compatibility with the prior art.

As shown in fig. 3, the present embodiment provides a session information query method, including:

step S210: an open function network element receives an AF request, wherein the AF request carries a network protocol IP address of UE;

step S220: the open function network element inquires a mapping relation according to the IP address of the UE to obtain the identification information of the session management function network element corresponding to the IP address of the UE, wherein the mapping relation is the IP address of the UE and the identification information of the session management function network element of the UE;

step S230: the open function network element sends a query request carrying the IP address of the UE to the identification information of the session management function network element;

step S240: the session management function network element inquires session information based on the IP address of the UE; wherein the session information at least comprises: identification information of a policy control network element of the UE;

step S250: and the session management function network element sends the session information of the policy control network element to the open function network element.

The open function network element can be NEF or SCEF, etc.; the session management function network element can be an SMF or a PCEF; the policy control network element may be a PCF or a PCRF.

In some embodiments, the method may further comprise: and the open function network element sends a request corresponding to the AF request to a corresponding policy control network element based on the identification information of the policy control network element.

After receiving the AF request sent by the AF, the open function network element locally queries a mapping relationship or queries a mapping relationship to an NRF to obtain identification information of a session management function network element corresponding to the IP address of the UE; and the UE sends the identification information of the strategy control network element corresponding to the UE to the session management function network element.

The session information further includes: at least one of a communication identification of the UE, a wireless communication type of the UE, and a quality of service (QoS) of the UE communication. The identification information of the session management function includes: at least one of a name, an Identification (ID), and an IP address of the session management function. The session information includes identification information of a policy control network element corresponding to the UE, and the identification information of the policy control network element includes: and at least one of the name, the ID and the IP address of the policy control network element.

In some embodiments, the method comprises: the open function network element prestores the mapping relation; the step S220 may include: and the open function network element locally inquires the mapping relation according to the IP address of the UE.

In other embodiments, the method further comprises: the NRF stores the mapping relation in advance; the step S220 may include: the open function network element sends a discovery request carrying the IP address of the UE to the NRF; and the open function network element receives the identifier information of the session management function network element returned by the NRF.

Optionally, the method further comprises:

the network discovery function network element receives a service registration request of a session management function network element; wherein, the service registration request carries an IP address set or an IP address field which can be allocated to the UE by the session management function network element;

the network discovery function network element establishes a mapping relation between the identification information of the session management function network element and the IP address of the UE according to the identification information of the session management function network element and the IP address set or the IP address field of the UE;

the step S220 may include:

the open function network element sends a discovery request carrying the IP address of the UE according to the IP address of the UE;

the network discovery function network element inquires the mapping relation based on the discovery request and sends the inquired address of the session management function network element to the open function network element;

and the open function network element receives the identification information of the session management function network element returned by the network discovery function network element.

The mapping relationship includes at least one of:

Correspondingly, the step S220 may include:

inquiring the mapping relation according to the public network IP address of the UE to obtain the identification information of the session management function network element;

inquiring the mapping relation according to the private network IP address of the UE and the domain identifier of the IP domain where the private network IP address is located, and acquiring the identifier information of the session management function network element;

inquiring the mapping relation according to the IPv4 address of the UE to obtain the identification information of the session management function network element;

and inquiring the mapping relation according to the IPv6 address of the UE to obtain the identification information of the network element with the session management function.

The step S230 may include:

and the open function network element sends a query request carrying the IP address of the UE to the identification information of the session management function network element. The IP address may be a public network IP address or a private network IP address of the UE. If the IP domain managed by one session management function network element is only one IP domain managed by one or more session management function network elements, the query request can carry the private network IP address alone to complete the query of the session information, and if the IP domains managed by one session management function network element are multiple, the query request not only needs to carry the private network IP address of the UE but also needs to carry the domain identification of the IP domain where the private network IP address is located.

It is worth noting that when the IP address of the UE carried by the application service request is a private network IP address, the application service request also needs to carry a domain identifier of an IP domain where the private network IP address is located.

As shown in fig. 4, this embodiment provides an open function network element, which may be a NEF or a PCEF, including:

a first receiving unit 110, configured to receive an application service request carrying a network protocol IP address of a user equipment UE;

a first querying unit 120, configured to query, according to the IP address of the UE, identification information of a session management function network element that performs session management on the UE;

a first sending unit 130, configured to send, based on the identification information of the session management function network element, an inquiry request carrying the IP address of the UE to a corresponding session management function network element;

a second receiving unit 140, configured to receive session information returned by the session management function network element based on the query request, where the session information at least includes: and the identification information of the strategy control corresponding to the UE.

The first receiving unit 110 may correspond to N5 in NEF in this embodiment, and may be configured to receive an AF request from an AF; or the interface between AF and PCEF.

The first query unit 120 may correspond to a processor, which may be a packaged processing chip or an unpackaged processing circuit, such as a central processing unit, a microprocessor, a digital signal processor, an application processor, a programmable array, or an application specific integrated circuit, which may perform information processing.

The first sending unit 130 may correspond to an interface between the NEF and the SMF or an interface between the PCEF and the PCRF, and may be configured to send the query request.

The second receiving unit 140 may also correspond to an interface between the NEF and the SMF or an interface between the PCEF and the PCRF, and may be configured to receive identification information of a policy control network element such as the PCF or the PCRF.

In some embodiments, the open functional network further comprises: the first configuration unit is used for pre-configuring the mapping relation between the identification information of the session management function network element and the IP address of the UE; the first querying unit 120 is specifically configured to locally query the mapping relationship according to the IP address of the UE to obtain the identification information of the SMF.

In other embodiments, the first querying unit 120 is specifically configured to send a discovery request carrying an IP address of the UE to a network discovery function NRF, where a mapping relationship between identification information of an SMF and the IP address of the UE is preconfigured in the NRF; and receiving the SMF identification information returned by the NRF, wherein the SMF identification information is determined by inquiring the mapping relation by taking the IP address of the UE as an inquiry basis.

The first querying unit 120 may correspond to a communication interface between the open function network element and the NRF, and may be used for information interaction between the NEF and the NRF.

In some embodiments, the second receiving unit 140 is specifically configured to receive the PCF identification information obtained by querying session information by the SMF, where the session information is a session record generated when the UE attaches to a network.

The mapping relationship between the identification information of the session management function network element and the IP address of the UE includes at least one of the following: mapping relation between the identification information of the session management function network element and the public network IP address of the UE; the mapping relation between the identification information of the session management function network element and the private network IP address of the UE and the domain identification of the IP domain where the private network IP address is located; mapping relation between the identification information of the session management function network element and the IPv4 address of the UE; and mapping relation between the identification information of the session management function network element and the IPv6 address of the UE.

The first querying unit 120 is specifically configured to query, according to the public network IP address of the UE, identification information of a session management function network element that performs session management on the UE; inquiring identification information of a session management function network element for performing session management on the UE according to the private network IP address of the UE and a domain identification corresponding to an IP domain where the private network IP address is located; according to the IPv4 address of the UE, inquiring identification information of a session management function network element for carrying out session management on the UE; and inquiring identification information of a session management function network element for performing session management on the UE according to the IPv6 address of the UE. As shown in fig. 5, the present embodiment further provides a network system, including:

the open function network element 210 is configured to receive an AF request sent by an application service AF, where the AF request carries a network protocol IP address of a user equipment UE; inquiring a mapping relation according to the IP address of the UE, wherein the mapping relation is the IP address of the UE and the identification information of the session management function and session management function network element 220 of the UE; sending an inquiry request carrying the IP address of the UE to the identification information of the session management function network element 220;

the session management function network element 220 is configured to query, based on the IP address of the UE, a session result generated when the UE attaches to a network, so as to obtain identification information of a policy control network element; sending the identification information of the policy control network element to the open function network element 210;

the open function network element 210 is further configured to send a request corresponding to the AF request to a corresponding policy control network element based on the identification information of the policy control network element.

Optionally, the open function network element 210 is further configured to store the mapping relationship in advance; when querying the mapping relationship, the open function network element 210 is specifically configured to locally query the mapping relationship by the open function network element 210 according to the IP address of the UE.

In some embodiments, the network system further comprises: NRF 230 for storing the mapping relationship in advance; the open function network element 210 is specifically configured to send a discovery request carrying the IP address of the UE to the NRF 230; receiving the identification information of the session management function network element 220 returned by the NRF 230.

As shown in fig. 6, this embodiment provides a session management function network element, which may be a session management function network element such as an SMF or a PCEF, and includes:

a third receiving unit 410, configured to receive an inquiry request that a network element with an open network function carries an IP address of a user equipment UE, where the inquiry request is sent when the network element with the open network function receives an application service request that carries the IP address of the UE;

a second querying unit 420, configured to query, based on the query request, session information generated in a session establishment procedure of the UE, where the session information at least includes: identification information of policy control corresponding to the UE;

a second sending unit 430, configured to send the session information to the network element.

The third receiving unit 410 and the second sending unit 430 both correspond to communication interfaces in a session management function network element, and the second querying unit 420 may correspond to various processors.

The session information includes at least one of: at least one of the identification information of the policy control network element of the UE, the communication identification of the UE, the wireless communication type of the UE and the QoS of the UE communication.

In further embodiments, the session management function network element further comprises:

and the forming unit is used for forming the session information based on the session result of the session flow when the UE requests attachment or switching. The session information at least includes: the IP address of the UE and the identification information of the policy control network element corresponding to the IP address of the UE, where the identification information of the policy control network element may be the IP address of the policy control network element or the ID of the policy control network element.

The mapping relationship includes at least one of: mapping relation between the identification information of the session management function network element and the public network IP address of the UE; the mapping relation between the identification information of the session management function network element and the private network IP address of the UE and the domain identification of the IP domain where the private network IP address is located; mapping relation between the identification information of the session management function network element and the IPv4 address of the UE; and mapping relation between the identification information of the session management function network element and the IPv6 address of the UE.

The second querying unit 420 may be specifically configured to query the mapping relationship according to the public network IP address of the UE, so as to obtain the identification information of the session management function network element; and/or inquiring the mapping relation according to the private network IP address of the UE and the domain identifier of the IP domain where the private network IP address is located to obtain the identifier information of the session management function network element; and/or inquiring the mapping relation according to the IPv4 address of the UE to obtain the identification information of the network element with the session management function; and/or inquiring the mapping relation according to the IPv6 address of the UE to obtain the identification information of the network element with the session management function.

As shown in fig. 7, this example further provides another network element, which may be the aforementioned session management function network element, open function network element, and the like, and may include: a memory 310, a processor 320, a transceiver 330, and a computer program 340 stored on the memory 310 and executed by the processor 320;

the processor 320 is respectively connected to the memory 310 and the transceiver 330, and configured to execute the computer program 340 to control information storage of the memory 310 and information transmission and reception of the transceiver 330, and implement the aforementioned session information query method applied to an open-function network element, or a session information query method applied to a session management function network element, or a session information query method applied to a communication system.

In this embodiment, the transceiver 330 may correspond to a network interface, and the network interface may be a cable interface and may be used for data interaction with other network elements.

The memory 310 may include: various types of storage media may be used for data storage. In this embodiment, the storage medium included in the memory 310 is at least partially a non-volatile storage medium, and can be used for storing the computer program 340.

The processor 320 may include: a central processor 320, a microprocessor 320, a digital signal processor 320, an application specific integrated circuit or programmable array, etc., may be used to effect the formation of PNF packets through execution of a computer program 340.

In this embodiment, the processor 320 may be connected to the transceiver 330 and the memory 310 through an intra-device bus such as an integrated circuit bus.

The embodiment of the invention also provides a computer storage medium, wherein the computer storage medium stores a computer program, and the computer program is executed by a processor and executes the policy control function session information query method provided in one or more embodiments. Specifically, the present invention may be one or more of the session information query methods applied in the aforementioned open function network element, or one or more of the session information query methods applied in the network system.

The computer storage medium provided by the embodiment of the invention comprises: a mobile storage device, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes. Alternatively, the computer storage medium may be a non-transitory storage medium. The non-transitory storage medium herein may also be referred to as a non-volatile storage medium.

The implementation of the invention also provides another session information query method, which is applied to NRF and comprises the following steps:

pre-configuring a mapping relation between identification information of a Session Management Function (SMF) and a network protocol (IP) address of User Equipment (UE);

receiving a discovery request which is sent by a network open function network element and carries an IP address of UE;

inquiring the mapping relation based on the IP address of the UE to obtain the identification information of the SMF corresponding to the IP address of the UE;

and sending the identification information of the SMF to the open function network element.

An embodiment of the present invention further provides an NRF, including:

the configuration unit is used for configuring the mapping relation between the identification information of the session management function SMF and the network protocol IP address of the user equipment UE in advance;

a fourth receiving unit, configured to receive a discovery request carrying an IP address of the UE sent by a network element with an open function;

a fifth query unit, configured to query the mapping relationship based on the IP address of the UE to obtain identification information of an SMF corresponding to the IP address of the UE;

a third sending unit, configured to send the identification information of the SMF to the open function network element.

The configuration unit herein may correspond to a memory including a non-transitory storage medium, and may store the mapping relationship.

The fourth receiving unit and the third sending unit may correspond to an interface between the open-function network element and the NRF, and may be used for interaction of the discovery request and the identification information of the SMF between the open-function network element and the NRF.

The third query unit, which may also correspond to the processor, may be configured to perform a query for identification information of the SMF.

Two specific examples are provided below in connection with any of the above embodiments:

example 1:

this example provides a session information query method, where before addressing a policy control network element, an IP address pool of an SMF is planned and a mapping relationship between the SMF and an IP address field is preconfigured in an open function network element, as shown in fig. 8, the method specifically includes:

step S1: planning an IP address pool of the SMF, and presetting a mapping relation between the SMF and the IP address field on the NEF.

Step S2: AF sends AF request to NEF;

step S3: the NEF queries the mapping relation between the SMF and the IP address field to find the address of the SMF managing the PDU session of the UE.

Step S4: the NEF sends PCF address inquiry request to the SMF, and the request carries the IP address of the UE.

Step S5: the SMF inquires the context of the UE according to the IP address of the UE to obtain the address of the PCF bound by the UE;

step S6: SMF returns address of binding PCF;

step S7: the NEF sends AF request to PCF according to PCF address.

Before executing the above procedure, PDU session establishment will be performed between the SMF and the PCF corresponding to the same UE, and PDU session release is also performed when the UE is powered off.

The present example further provides a PCF addressed network system comprising: NEF and SMF:

1) NEF may be used to perform the following operations:

and presetting the mapping relation between the SMF and the IP address field.

After receiving a service request of the UE sent by the AF, inquiring the mapping relation between the SMF and the IP address field to find out the address of the SMF for managing the PDU session of the UE.

And initiating a request for inquiring the PCF address to the SMF, wherein the request carries the IP address of the user.

And sending the AF request after mapping to the PCF according to the query result (the address of the binding PCF) returned by the SMF.

2) SMF may be used to perform the following operations:

an IP address is assigned to the UE.

A PCC session is established to the PCF. The PCF address is saved in the user context after the session is established. (the UE's code number, IP address, session ID, etc. information is already contained in the user context).

After receiving the inquiry request of NEF, inquiring the user context according to the IP address, and returning the address of the binding PCF.

Example 2:

this example provides a session information query method, where before PCF addressing, an IP address pool of an SMF is planned and an NRF pre-configures a mapping relationship between the SMF and an IP address segment, as shown in fig. 9, which may specifically include:

step S11: planning an IP address pool of the SMF, and presetting a mapping relation between the SMF and the IP address field on the NRF.

Step S12: the AF sends an AF request to the NEF.

Step S13: the NEF initiates a query request of the SMF address to the NRF, and the query request carries the IP address of the UE: specifically, if the NEF has no mapping relationship and no PCF address, the NRF is queried to obtain the SMF address;

step S14: the NRF returns the address of the SMF based on the mapping relation;

step S15: NEF sends PCF address inquiry request to SMF, carrying UE IP address,

step S16: SMF inquires UE context according to IP address, and returns address of binding PCF.

Step S17: the NEF sends an AF request to the PCF.

The present example also provides a network system, including: NRF, NEF and SMF.

NRF operable to perform the steps of:

presetting a mapping relation between the SMF and the IP address field;

and receiving a service discovery request of the NEF, and inquiring the mapping relation between the SMF and the IP address field to find the address of the SMF for managing the PDU session of the UE. The SMF address is returned.

NEF, operable to perform the steps of:

after receiving a service request of UE sent by AF, NEF does not configure mapping table and PCF address, and initiates a service discovery request to NRF, carrying service ID, user IP address and the like of SMF;

receiving SMF address returned by NRF, and sending PCF address query request to SMF, carrying IP address of user;

SMF operable to perform the steps of:

allocating an IP address for the UE;

a PCC session is established to the PCF. The PCF address is saved in the user context after the session is established. (information such as the number, IP address, session ID, etc. of the UE has been included in the user context);

Example 3:

according to 23.501, in roaming scenarios, the SMF that performs session management and allocates the IP address of the UE and the PCF that has PDU session may be in the same PLMN.

If a Local breakout roaming scheme is adopted, session management is carried out, an SMF with an IP address and a PCF with a PDN session are in a visiting network (namely a visited network), an NEF address pre-configured by AF is the visiting network NEF, and vSMF is inquired through the visiting network NEF.

If a home routed roaming scheme is adopted, session management is carried out, an SMF of an IP address of UE and a PCF with a PDN session are allocated in a home network (home network), a NEF address pre-configured by AF is the home network NEF, and the hSMF is inquired through the home network NEF.

Because the NEF and the SMF are also in the same PLMN, the mapping relation between the SMF and the IP address field of the same PLMN can be configured on the NEF; the mapping relationship between the SMF and the IP address field of the PLMN may also be configured on the NRF of the PLMN. The scheme is applicable to roaming scenarios.

Example 4:

as shown in fig. 10, the present example provides a method for creating or updating a mapping relationship, including:

a session management function network element sends a service registration request to an NRF, wherein the service registration request carries an IP address set or an IP address field which can be allocated for UE by the network element;

establishing a mapping table according to the identifier of the session management function network element and an IP address set or an IP address segment carried by the service registration request, wherein the mapping table can be one of the mapping relations;

adjusting the IP address set or IP address field plan of the session management function network element;

a session management function network element sends a service updating request to an NRF, wherein the service updating request carries an IP address set or an IP address field which can be allocated for UE;

and the NRF updates the mapping table according to the identification of the session management function network element and the IP address set or the IP address segment carried in the service updating request.

Example 5:

as shown in fig. 11, this example provides another method for creating or updating a mapping relationship, including:

the open function network element queries an address list of session management function network elements of the whole network from the NRF, where the address list may include information such as an address or an identifier of the session management function network element.

The open function network element receives the address list of the session management function network element of the whole network returned by the NRF;

an open function network element subscribes an IP address set or an IP address field which is managed by the SMF and can be allocated to the UE to the SMF of the whole network;

the session management function network element returns an IP address set or an IP address field which is managed by the session management function network element and can be allocated to the UE to the open function network element initiating the subscription;

the open function network element establishes a mapping table according to the identification of the session management function network element and the returned IP address set or IP address field;

the session management function network element returns an IP address set or an IP address field which is managed by the session management function network element and can be allocated to the UE to the subscribed open function network element;

and the open function network element establishes a mapping table according to the identifier of the session management function network element and the returned IP address set or IP address segment.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. The above-described device embodiments are merely illustrative, for example, the division of the unit is only a logical functional division, and there may be other division ways in actual implementation, such as: multiple units or components may be combined, or may be integrated into another system, or some features may be omitted, or not implemented. In addition, the coupling, direct coupling or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between the devices or units may be electrical, mechanical or other forms.

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, that is, 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, all the functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may be separately used as one unit, or two or more units may be integrated into one unit; the integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

Those of ordinary skill in the art will understand that: all or part of the steps for implementing the method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer readable storage medium, and when executed, the program performs the steps including the method embodiments; and the aforementioned storage medium includes: a mobile storage device, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention 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 invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A method for inquiring session information is applied to a network element with a network open function, and comprises the following steps:

2. The method of claim 1,

the session information further includes: at least one of a communication identification of the UE, a wireless communication type of the UE, and a quality of service (QoS) of the UE communication.

3. The method according to claim 1 or 2,

4. The method of claim 1,

the method further comprises the following steps:

pre-configuring a mapping relation between identification information of a session management function network element and an IP address of UE;

the querying, according to the IP address of the UE, identification information of a session management function network element that performs session management on the UE includes:

5. The method of claim 1,

the querying, according to the IP address of the UE, an address of a network element with a session management function for performing session management on the UE includes:

sending a discovery request carrying the IP address of the UE to a network discovery function network element, wherein the network discovery function network element is pre-configured with a mapping relation between identification information of a session management function network element and the IP address of the UE;

and receiving the identification information of the session management function network element returned by the network discovery function network element, wherein the identification information of the session management function network element is determined by inquiring the mapping relation by taking the IP address of the UE as an inquiry basis.

6. The method according to claim 4 or 5,

the mapping relationship includes at least one of:

the mapping relation between the identification information of the session management function network element and the IP address field of the UE managed by the session management function network element;

and the mapping relation between the identification information of the session management function network element and the IP address set of the UE managed by the session management function network element.

7. The method of claim 4, further comprising:

sending a query request of the address of the session management function network element to the network discovery function network element;

sending a subscription request to a session management function network element based on the address returned to the session management function network element; the subscription request is used for sending the IP address set or the IP address field to the network open function network element when the IP address set or the IP address field managed by the session management function network element is triggered to change;

and updating the mapping relation between the identification information of the session management function network element and the IP address of the UE according to the IP address set or the IP address field and the identification information of the session management network element.

8. The method of claim 1, further comprising:

sending a subscription request to a session management function network element based on the returned address of the session management function network element; the subscription request is used for triggering an IP address set or an IP address field planned and managed by the session management function network element, or sending the IP address set and the IP address field to the network open function network element when the managed IP address set or the IP address field is changed;

creating or updating a mapping relation between the identification information of the session management function network element and the IP address of the UE according to the IP address set or the IP address field and the identification information of the session management network element;

and inquiring the mapping relation according to the IP address of the UE.

9. The method of claim 4, 5, 7 or 8,

the mapping relationship between the identification information of the session management function network element and the IP address of the UE includes at least one of the following:

10. The method of claim 9,

the querying, according to the IP address of the UE, identification information of a session management function network element that performs session management on the UE includes at least one of:

11. The method of claim 1,

the receiving of the identification information of the policy control network element returned by the session management function network element based on the query request includes:

and receiving the identification information of the policy control network element, which is obtained by the session management function network element through inquiring session information, wherein the session information is a session record generated in the UE session establishment process.

12. A method for inquiring session information is applied to a network element with session management function, and comprises the following steps:

13. The method of claim 12,

the session information includes at least one of:

at least one of the identification information of the policy control network element of the UE, the communication identification of the UE, the wireless communication type of the UE and the QoS of the UE communication.

14. A method for querying session information, comprising:

a network open function network element receives an application service request, wherein the application service request carries a network protocol IP address of User Equipment (UE);

the network open function network element queries a mapping relation according to the IP address of the UE to obtain identification information of a session management function network element corresponding to the IP address of the UE, wherein the mapping relation is as follows: the corresponding relation between the IP address of the UE and the identification information of the session management function network element of the UE;

the network open function network element sends a query request carrying the IP address of the UE to a session management function network element according to the identification information of the session management function network element;

and the session management function network element sends the session information to the network open function network element.

15. The method of claim 14,

the method comprises the following steps:

the network open function network element prestores the mapping relation;

the network open function network element inquiring the mapping relation according to the IP address of the UE comprises the following steps:

and the network open function network element locally inquires the mapping relation according to the IP address of the UE.

16. The method of claim 14,

the method further comprises the following steps:

the network discovery function network element stores the mapping relation in advance;

the network open function network element sends a discovery request carrying the IP address of the UE to the network discovery function network element;

and the network open function network element receives the identification information of the session management function network element returned by the network discovery function network element.

17. The method of claim 14,

the method further comprises the following steps:

the network discovery function network element receives a service registration request of a session management function network element; wherein, the service registration request carries an IP address set or an IP address field managed by the session management network element or an updated IP address set or an IP address field;

the network discovery function network element creates or updates the mapping relation between the identification information of the session management function network element and the IP address of the UE according to the IP address set or the IP address section and the identification information of the session management function network element;

the network open function network element sends a discovery request carrying the IP address of the UE according to the IP address of the UE;

the network discovery function network element inquires the mapping relation based on the discovery request and sends the inquired address of the session management function network element to the network open function network element;

18. The method according to any one of claims 14 to 17,

the mapping relationship includes at least one of:

19. The method of claim 18,

the network open function network element querying a mapping relation according to the IP address of the UE to obtain the identification information of the session management function network element corresponding to the IP address of the UE, including:

20. A network open function network element, comprising:

21. A session management function network element, comprising:

22. A network open function network element, comprising: a memory, a processor, a transceiver, and a computer program stored on the memory and executed by the processor;

the processor, connected to the memory, is configured to control information storage of the memory and information transmission and reception of the transceiver by executing the computer program, and implement the session information query method provided in any one of claims 1 to 11.

23. A session management function network element, comprising: a memory, a processor, a transceiver, and a computer program stored on the memory and executed by the processor;

the processor, connected to the memory, is configured to control information storage of the memory and information transmission and reception of the transceiver by executing the computer program, and implement the session information query method provided in any one of claims 12 to 13.

24. A computer storage medium having a computer program stored thereon; the computer program, when executed by a processor, is capable of implementing a session information query method as provided in any one of claims 1 to 11, 12 to 13, or 14 to 19.