Session control method, system and SMF network element

Abstract

The present disclosure provides a session control method, system and SMF network element, which relate to the field of communication technology. The method comprises: a session management function SMF network element responds to a first session establishment request from a relay user equipment UE, and establishes a first group session for the relay UE, wherein the first session establishment request carries a first group session parameter; the SMF network element responds to a second session establishment request from the relay UE, and establishes a second group session for the relay UE for group communication with a remote UE, wherein the second session establishment request carries a second group session parameter, and the second group session parameter is different from the first group session parameter; the SMF network element performs session control on the first group session and the second group session in corresponding groups respectively, and when the remote UE and the relay UE belong to the same group, performs session control on the first group session and the second group session as group sessions of the same group.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to a session control method, system and SMF network element. Background Art

[0002] In order to expand the communication range, a remote user equipment (UE) outside the coverage of the communication network can be connected to the communication network through a relay UE with UE-to-network relay capability within the coverage of the communication network, and then communicate with the communication network. Here, the remote UE generally refers to an off-network device outside the coverage of the communication network, and the relay UE with UE-to-network relay capability refers to an on-network device within the coverage of the communication network that can provide relay services for communication between the remote UE and the communication network.

[0003] In the related art, in certain scenarios (for example, in the scenario of L3 relay networking and no non-3GPP Inter Working Function (N3IWF) network element), each group in the network has a group session parameter for identifying the group. The relay UE can initiate a session establishment request to the Session Management Function (SMF) network element according to the group session parameter of the group to which it belongs, so as to request the SMF network element to establish a corresponding group session for itself. The relay UE can also initiate a session establishment request to the SMF network element for the group session parameter of the group to which the remote UE belongs, so as to request the SMF network element to establish a group session for the remote UE to perform group communication. Summary of the invention

[0004] The inventor noticed that in the related art, when the relay UE and the remote UE that accesses the network via the relay UE belong to the same group, since the group session parameters used by the relay UE and the remote UE for group communication are the same, the SMF network element cannot distinguish between the session establishment request initiated by the relay UE for its own group communication and the session establishment request initiated by the relay UE for the remote UE for group communication, resulting in the SMF network element being unable to establish corresponding group sessions for the group communications of both the relay UE and the remote UE, thereby resulting in the relay UE and the remote UE that accesses the network via the relay UE being unable to conduct group communication at the same time.

[0005] In order to solve the above problems, the embodiments of the present disclosure propose the following solutions.

[0006] According to one aspect of an embodiment of the present disclosure, a session control method is provided, including a session management function SMF network element responding to a first session establishment request from a relay user equipment UE, establishing a first group session for the relay UE, the first session establishment request carrying a first group session parameter; the SMF network element responding to a second session establishment request from the relay UE, establishing a second group session for the relay UE for group communication with a remote UE, the second session establishment request carrying a second group session parameter, and the second group session parameter is different from the first group session parameter; the SMF network element performs session control on the first group session and the second group session in corresponding groups respectively, and when the remote UE and the relay UE belong to the same group, performs session control on the first group session and the second group session as group sessions of the same group.

[0007] In some embodiments, the SMF network element determines the group to which the remote UE belongs and the group to which the relay UE belongs based on the first group session parameter and the second group session parameter.

[0008] In some embodiments, the method also includes: the SMF network element receives information from the relay UE, the information including a first correspondence between a first relay service code RSC and the second group session parameter; the SMF network element determines whether the first RSC and the second RSC are the same based on the first correspondence and a second correspondence between the first group session parameter and the second RSC; the SMF network element determines that the remote UE and the relay UE belong to the same group when the first RSC and the second RSC are the same.

[0009] In some embodiments, the data network name DNN in the first group session parameter is different from the DNN in the second group session parameter; and / or the single network slice selection assistance information S-NSSAI in the first group session parameter is different from the S-NSSAI in the second group session parameter.

[0010] In some embodiments, the remote UE accesses the core network via the relay UE in the L3 network, and the access to the core network does not pass through a non-3GPP interworking function N3IWF network element.

[0011] In some embodiments, the method also includes: the SMF network element receives the IP address of the remote UE sent by the relay UE, and the IP address of the remote UE is different from the IP address of the relay UE.

[0012] In some embodiments, the method also includes: the direct discovery name management function DDNMF network element receives an address allocation request from the relay UE, the address allocation request carries the IP address of the relay UE and the identifier of the remote UE; and sends the IP address of the remote UE allocated to the remote UE to the relay UE.

[0013] In some embodiments, the IP address of the remote UE and the IP address of the relay UE are located in the same network segment.

[0014] In some embodiments, the IP address of the remote UE is an IPv4 address.

[0015] In some embodiments, the method also includes: the SMF network element receives session context update information of the relay UE from the DDNMF network element, and the session context update information includes the correspondence between the IP address of the relay UE and the IP address of the remote UE; the SMF network element performs session control on the first group session and the second group session as group sessions of the same group, including: the SMF network element constructs a session control policy based on the session context update information, treating the first group session and the second group session as group sessions of the same group, and the session control policy includes a group session forwarding policy.

[0016] In some embodiments, the first group session and the second group session are both virtual network VN group sessions.

[0017] According to another aspect of an embodiment of the present disclosure, a SMF network element is provided, including: a session establishment module, configured to establish a first group session for the relay UE in response to a first session establishment request from the relay UE, the first session establishment request carrying a first group session parameter; and to establish a second group session for the remote UE in response to a second session establishment request from the relay UE, the second session establishment request carrying a second group session parameter, the second group session parameter being different from the first group session parameter; a session control module, configured to perform session control on the first group session and the second group session in corresponding groups respectively, and when the remote UE and the relay UE belong to the same group, perform session control on the first group session and the second group session as group sessions of the same group.

[0018] According to another aspect of an embodiment of the present disclosure, there is provided an SMF network element, comprising: a memory; and a processor coupled to the memory, wherein the processor is configured to execute the method described in any one of the above embodiments based on instructions stored in the memory.

[0019] According to another aspect of an embodiment of the present disclosure, a session control system is provided, comprising: the SMF network element described in any one of the above embodiments, and the DDNMF network element, configured to receive an address allocation request from the relay UE, the address allocation request carrying the IP address of the relay UE and the identifier of the remote UE; and sending the IP address of the remote UE allocated to the remote UE to the relay UE.

[0020] In some embodiments, the system further includes: a relay UE configured to send the first session establishment request and the second session establishment request to the SMF network element, and to send the address allocation request to the DDNMF network element.

[0021] According to another aspect of an embodiment of the present disclosure, a computer-readable storage medium is provided, comprising computer program instructions, wherein when the computer program instructions are executed by a processor, the method described in any one of the above embodiments is implemented.

[0022] According to another aspect of the embodiments of the present disclosure, a computer program product is provided, including a computer program, wherein when the computer program is executed by a processor, the method described in any one of the above embodiments is implemented.

[0023] In the disclosed embodiment, the SMF network element can establish a group session for the relay UE to perform group communication itself and a group session for the remote UE to access the network via the relay UE according to two different group session parameters, and when the remote UE and the relay UE belong to the same group, the two group sessions can be used as group sessions of the same group for session control. In this way, the SMF network element can distinguish the session establishment request initiated by the relay UE for group communication itself and the session establishment request initiated by the relay UE for group communication for the remote UE according to the two different group session parameters, so as to respectively establish a group session for the relay UE to perform group communication itself and a group session for the remote UE to perform group communication, thereby avoiding the problem that the SMF network element cannot establish group sessions for both the relay UE and the remote UE when the relay UE and the remote UE to access the network via the relay UE belong to the same group, thereby allowing the relay UE and the remote UE to perform group communication at the same time.

[0024] The technical solution of the present disclosure is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is a flowchart of a session control method according to some embodiments of the present disclosure;

[0027] Figure 2 is a flowchart of a session control method according to other embodiments of the present disclosure;

[0028] Figure 3 is a flowchart of a session control method according to some other embodiments of the present disclosure;

[0029] Figure 4 is a flowchart of a session control method according to some further embodiments of the present disclosure;

[0030] Figure 5 is a schematic diagram of the structure of an SMF network element according to some embodiments of the present disclosure;

[0031] Figure 6 is a schematic diagram of the structure of an SMF network element according to other embodiments of the present disclosure;

[0032] Figure 7 It is a structural diagram of a conversation control system according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0034] Unless specifically stated otherwise, the relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure.

[0035] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0036] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0037] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0038] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0039] Figure 1 It is a flowchart of a session control method according to some embodiments of the present disclosure.

[0040] In step 102, the SMF network element establishes a first group session for the relay UE in response to a first session establishment request from the relay UE.

[0041] Here, the first session establishment request carries the first group session parameter.

[0042] It should be understood that the first group session is a group session used to relay the UE itself to perform group communication.

[0043] In some embodiments, the first group session may be a virtual network (VN) group session, and the first group session parameters may include a data network name (DNN) and single network slice selection assistance information (S-NSSAI).

[0044] In step 104, the SMF network element establishes a second group session for the relay UE for group communication with the remote UE in response to the second session establishment request from the relay UE.

[0045] Here, the second session establishment request carries a second group session parameter, and the second group session parameter is different from the first group session parameter.

[0046] It should be understood that the remote UE is a UE that accesses the network via a relay UE. For example, the remote UE can select a relay UE by initiating a relay discovery process, and can establish a relay connection (eg, PC5 connection) with the relay UE to access the network through the relay UE.

[0047] In some embodiments, the second group session may be a VN group session, and the second group session parameters may include DNN and S-NSSAI.

[0048] In some embodiments, the DNN in the first group session parameters is different from the DNN in the second group session parameters; and / or the S-NSSAI in the first group session parameters is different from the S-NSSAI in the second group session parameters.

[0049] In step 106, the SMF network element performs session control on the first group session and the second group session in the corresponding groups respectively, and when the group to which the remote UE belongs and the group to which the relay UE belongs are the same group, the first group session and the second group session are session controlled as group sessions of the same group.

[0050] For example, the SMF network element can perform session control on the first group session in the corresponding group (for example, the group to which the relay UE belongs), and perform session control on the second group session in the corresponding group (for example, the group to which the remote UE belongs). When the remote UE and the relay UE belong to the same group, the SMF network element will perform session control on the first group session and the second group session according to the session management policy of the same group.

[0051] In the above embodiment, the SMF network element can establish a group session for the relay UE to perform group communication itself and a group session for the remote UE to access the network via the relay UE for group communication respectively according to two different group session parameters, and when the remote UE and the relay UE belong to the same group, the two group sessions can be used as group sessions of the same group for session control. In this way, the SMF network element can distinguish the session establishment request initiated by the relay UE for group communication itself and the session establishment request initiated by the relay UE for group communication for the remote UE according to the two different group session parameters, so as to respectively establish a group session for the relay UE to perform group communication itself and a group session for the remote UE to perform group communication, thereby avoiding the problem that the SMF network element cannot establish group sessions for both the relay UE and the remote UE when the relay UE and the remote UE to access the network via the relay UE belong to the same group, thereby allowing the relay UE and the remote UE to perform group communication at the same time.

[0052] In some embodiments, the relay UE is a UE in the L3 network, and the remote UE can access the core network via the relay UE in the L3 network without accessing the N3IWF network element. In this way, in the scenario of L3 relay networking and accessing the core network without N3IWF network elements, the relay UE and the remote UE can perform group communication at the same time. That is, the method provided in the embodiment of the present disclosure can solve the technical problem that the relay UE and the remote UE accessing the network via the relay UE cannot perform group communication at the same time in the scenario of L3 relay networking and no N3IWF network element.

[0053] In some embodiments, the SMF network element may determine whether the remote UE and the relay UE belong to the same group based on the first group session parameter and the second group session parameter.

[0054] As some implementation methods, the SMF network element can determine that the remote UE and the relay UE belong to the same group (i.e., the VN group) based on the correspondence between the first group session parameter, the second group session parameter, and a certain group (e.g., the VN group). The correspondence can, for example, be pre-set in the SMF network element, or can be obtained by the SMF network element from a network exposure function (NEF) network element or a policy control function (PCF) network element.

[0055] As another implementation, the SMF network element can also combine the information from the relay to determine whether the remote UE and the relay UE belong to the same group. Figure 2 This is further explained.

[0056] Figure 2 It is a flowchart of a session control method according to some other embodiments of the present disclosure.

[0057] and Figure 1 Compared with the embodiment shown, Figure 2 The method shown further includes steps 202 to 206 .

[0058] In step 202, the SMF network element receives information from the relay UE.

[0059] Here, the information from the relay UE includes a first corresponding relationship between a first relay service code (Relay Service Code, RSC) and a second group session parameter.

[0060] In some embodiments, the first RSC may be an RSC for the remote UE to perform relay service discovery. In these embodiments, the remote UE may initiate a relay discovery process according to the first RSC to select a relay UE, wherein a first correspondence between the first RSC and the second group session parameter may be pre-set in the relay UE. The first correspondence may be, for example, "second group session parameter-first RSC-second group".

[0061] In some embodiments, after establishing a relay connection with a remote UE, the relay UE may, based on the first correspondence, use the second group session parameter to initiate a session establishment request to the SMF network element to request the SMF network element to establish a second group session for the remote UE to perform group communication. When the relay UE determines that the first group to which it belongs and the second group identified by the second group session parameter are the same group, the relay UE may report the first correspondence to the SMF network element.

[0062] In step 204, the SMF network element determines whether the first RSC and the second RSC are the same according to the first corresponding relationship and the second corresponding relationship between the first group session parameter and the second RSC.

[0063] In some embodiments, the second correspondence between the first group session parameter and the second RSC may be preset in the SMF network element, or the SMF network element may obtain the second correspondence from the NEF network element or the PCF network element. The second correspondence may be, for example, "first group session parameter-second RSC-first group".

[0064] In some embodiments, the SMF network element can determine that the first RSC corresponds to the second group session parameter (i.e., corresponds to the second group to which the remote UE belongs) based on the first correspondence relationship; the SMF network element can determine that the second RSC corresponds to the first group session parameter (i.e., corresponds to the first group to which the relay UE belongs) based on the second correspondence relationship; accordingly, the SMF network element can determine whether the first RSC and the second RSC are the same by comparing the first RSC in the first correspondence relationship and the second RSC in the second correspondence relationship, and further determine whether the first group identified by the first group session parameter and the second group identified by the second group session parameter are the same (i.e., determine whether the relay UE and the remote UE belong to the same group).

[0065] In step 206, the SMF network element determines that the remote UE and the relay UE belong to the same group when the first RSC and the second RSC are the same.

[0066] For example, when it is determined that the first RSC and the second RSC are the same (that is, the first group session parameter and the second group session parameter correspond to the same RSC), the SMF network element can determine that the first group identified by the first group session parameter and the second group identified by the second group session parameter are the same group, that is, it can be determined that the relay UE and the remote UE belong to the same group, so that the first group session and the second group session can be treated as group sessions of the same group for session control.

[0067] It should be understood that when it is determined that the first RSC and the second RSC are different (that is, the first group session parameter and the second group session parameter correspond to two different RSCs respectively), the SMF network element can determine that the first group identified by the first group session parameter and the second group identified by the second group session parameter are different, that is, it can be determined that the relay UE and the remote UE do not belong to the same group, so that the first group session and the second group session can be treated as group sessions of different groups for session control respectively.

[0068] In the above embodiment, the SMF network element can determine whether the relay UE and the remote UE belong to the same group by determining that the RSC corresponding to the first group session parameter and the RSC corresponding to the second group session parameter are the same. In this way, by using the same RSC to make different group session parameters of the same group correspond to each other, the SMF network element can determine that the relay UE and the remote UE belong to the same group based on the first group session parameter and the second group session parameter corresponding to the same RSC, thereby ensuring that the SMF network element can perform session control on the established first group session and the second group session as group sessions of the same group, thereby improving the reliability of group communication between the relay UE and the remote UE.

[0069] In some embodiments, the SMF network element may determine the group to which the remote UE belongs and the group to which the relay UE belongs based on the first group session parameter and the second group session parameter. For example, the SMF network element may determine that the group to which the relay UE belongs is the first group identified by the first group session parameter based on the correspondence between the group session parameter and the group, and the SMF network element may determine that the group to which the remote UE belongs is the second group identified by the second group session parameter based on the correspondence between the group session parameter and the group; for another example, the correspondence between the group session parameter, the RSC and the group may be pre-set in the SMF network element. In this case, for example, the SMF network element may determine that the group to which the remote UE belongs is the second group corresponding to the first RSC when the group session parameter is the second group session parameter and the RSC is the first RSC used by the remote UE for relay service discovery.

[0070] The inventors also noticed that in the related art, in certain scenarios (such as L3 relay networking scenarios), when multiple remote UEs access the network through the same relay UE, the relay UE will allocate multiple IP addresses to these multiple remote UEs one by one through Network Address Port Transfer (NAPT).

[0071] However, the relay UE allocates the relay UE's own IP address to each of the multiple remote UEs through NAPT. However, in order to distinguish the multiple remote UEs, the relay UE will also allocate a port number to the multiple remote UEs one by one, and then each remote UE will use the combination of the relay UE's IP address and the allocated port number for subsequent service access. In this way, the port number used by the remote UE in the process of subsequent service access may not be the original port number when the service access was initiated, resulting in the remote UE's uplink data packets being unable to be correctly forwarded when accessing some services using specific port numbers, resulting in low reliability of remote UE service implementation.

[0072] In view of this, the embodiments of the present disclosure also provide the following solutions.

[0073] Figure 3 It is a flowchart of a session control method according to some other embodiments of the present disclosure.

[0074] and Figure 1 Compared with the embodiment shown, Figure 3 The method shown further includes steps 302 to 304 .

[0075] In step 302, a Direct Discovery Name Management Function (DDNMF) network element receives an address allocation request from a relay UE.

[0076] Here, the address allocation request carries the IP address of the relay UE and the identifier of each remote UE in the multiple remote UEs corresponding to the relay UE. "Multiple remote UEs corresponding to the relay UE" means that the multiple remote UEs all access the network through the relay UE.

[0077] In some embodiments, the address allocation request from the relay UE may be one or more. For example, one address allocation request from the relay UE may carry the IP address of the relay UE and the identifier of each remote UE in multiple remote UEs, that is, the relay UE may request to allocate IP addresses for multiple remote UEs by sending one address allocation request; for another example, each of the multiple address allocation requests from the relay UE may carry the IP address of the relay UE and the identifier of a remote UE, that is, the relay UE may request to allocate IP addresses for multiple remote UEs respectively by sending multiple address allocation requests.

[0078] In some embodiments, the IP address of the relay UE can be allocated by the SMF network element or the user plane function (UPF) network element when the relay UE accesses the network through the NR interface.

[0079] In step 304, the DDNMF network element sends multiple IP addresses allocated to multiple remote UEs to the relay UE.

[0080] Here, the multiple IP addresses allocated to the multiple remote UEs are different from each other. For example, the two IP addresses allocated to the two remote UEs corresponding to the relay UE may be 128.16.10.7 and 123.16.10.8 respectively.

[0081] In some embodiments, the relay UE may forward the received multiple IP addresses to multiple remote UEs in a one-to-one correspondence.

[0082] In the above embodiment, the DDNMF network element sends multiple different IP addresses allocated to multiple remote UEs accessing the network through the relay UE to the relay UE according to the address allocation request from the relay UE. In this way, since the multiple IP addresses allocated by the DDNMF network element to the multiple remote UEs are different, the relay UE can distinguish the multiple remote UEs according to the multiple IP addresses, and there is no need to assign an additional port number to each remote UE. That is, each remote UE can retain the original port number when initiating service access after accessing the network, avoiding the impact of the change of the port number on the uplink data packet forwarding of the remote UE, thereby improving the reliability of the remote UE service implementation.

[0083] In addition, the DDNMF network element allocates addresses to remote UEs instead of the relay UE performing NAPT to allocate addresses to remote UEs. This can not only reduce changes to the existing network architecture, but also reduce performance requirements for the relay UE, which is conducive to the implementation of relay services.

[0084] In some embodiments, each remote UE can access the core network via a relay UE in the L3 network. In this way, the reliability of remote UE service implementation in the L3 relay networking scenario can be improved, that is, the technical problem that the remote UE cannot implement some services in the L3 relay networking scenario, resulting in low reliability of remote UE service implementation, can be solved.

[0085] In some embodiments, the IP address of each remote UE may be an IPv4 address, that is, the IP address allocated by the DDNMF network element to each remote UE may be an IPv4 address. In this way, the impact of the change of the port number on the forwarding of uplink data packets of remote UEs that do not support IPv6 addresses but support IPv4 addresses can be avoided, thereby improving the reliability of such remote UE service implementation.

[0086] In some embodiments, the IP address of each remote UE accessing the network via the relay UE may be in the same network segment as the IP address of the relay UE. For example, the IP address of the relay UE may be 128.16.10.6, and the three IP addresses allocated by the DDNMF network element to the three remote UEs accessing the network via the relay UE may be 128.16.10.7, 128.16.10.8, and 128.16.10.9, respectively. In this way, it is beneficial for the network side to implement routing aggregation for the forwarding paths of multiple remote UEs accessing the network via the relay UE and the relay UE, reducing the workload of the network side for routing settings, thereby reducing the consumption of network resources.

[0087] In some embodiments, each of the multiple IP addresses allocated to multiple remote UEs is different from the IP address of the relay UE. For example, the address pool used by the DDNMF network element to allocate addresses to remote UEs can be distinguished from the address pool used by the SMF network element and the UPF network element to allocate addresses to relay UEs, thereby making the IP address of the relay UE allocated by the SMF network element or the UPF network element and the multiple IP addresses allocated by the DDNMF network element to multiple remote UEs different from each other. In this way, when receiving a downlink data packet from the data network, the relay UE can determine whether it needs to be forwarded to the corresponding remote UE based on the IP address of the downlink data packet, thereby improving the reliability of the remote UE receiving the downlink data packet, thereby further improving the reliability of the remote UE service implementation.

[0088] In some embodiments, the SMF network element may receive the IP address of the remote UE sent by the relay UE, wherein the IP address of the remote UE is different from the IP address of the relay UE.

[0089] In some embodiments, the SMF network element can receive session context update information of the relay UE from the DDNMF network element, and the session context update information includes the correspondence between the IP address of the relay UE and the IP address of the remote UE. In this way, the SMF network element can not only distinguish the uplink and downlink data packets of multiple remote UEs, but also determine that the corresponding relay UE forwards the uplink and downlink data packets of multiple remote UEs, that is, it can ensure that the SMF network element can correctly route the uplink and downlink data packets of the remote UE, thereby further improving the reliability of the remote UE service implementation.

[0090] In these embodiments, as some implementations of step 106, the SMF network element may construct a session control policy including a group session forwarding policy by treating the first group session and the second group session as group sessions of the same group based on the session context update information, and construct a group session forwarding plane of the same group together with the UPF network element. For example, the group session forwarding plane may include a session forwarding path between SMF network elements or UPF network elements serving the same group to which the relay UE and the remote UE belong, and the session control policy of the same group to which the relay UE and the remote UE belong may also include a Quality of Service (QOS) policy.

[0091] In some embodiments, the SMF network element can update the forwarding table of the UPF network element according to the session context update information. In these embodiments, the updated forwarding table in the UPF network element also includes the correspondence between the IP address of the relay UE and the multiple IP addresses allocated to the multiple remote UEs. For example, in the case where the downlink data packet of the remote UE arrives at the UPF network element, the UPF network element can forward the downlink data packet of the remote UE to the corresponding relay UE according to the updated forwarding table, so that the relay UE correctly forwards the downlink data packet to the remote UE, that is, the UPF network element can correctly forward the data packet of the remote UE according to the updated forwarding table, so that the remote UE can interact with the data network.

[0092] In this way, the UPF network element can also distinguish the uplink and downlink data packets of multiple remote UEs and can determine that the corresponding relay UE will forward the uplink and downlink data packets of multiple remote UEs. That is, it can ensure that the UPF network element can correctly route the uplink and downlink data packets of the remote UE, thereby further improving the reliability of the remote UE service implementation.

[0093] Figure 4 It is a flowchart of a session control method according to some further embodiments of the present disclosure.

[0094] In step 402, the SMF network element receives a first session establishment request from the relay UE and establishes a first group session for the relay UE.

[0095] Here, the first session establishment request carries a first group session parameter, and the first group session parameter may identify the group to which the relay UE belongs.

[0096] In some embodiments, the first group session may be a VN group session, and the first group session parameters may include DNN and S-NSSAI to identify the VN group to which the relay UE belongs.

[0097] In step 404, the SMF network element receives a second session establishment request from the relay UE, and establishes a second group session for the relay UE for group communication with the remote UE.

[0098] Here, the second session establishment request carries a second group session parameter, and the second group session parameter is different from the first group session parameter.

[0099] In some embodiments, the second group session may be a VN group session, and the second group session parameters may include a DNN and an S-NSSAI to identify the VN group to which the remote UE belongs.

[0100] In some embodiments, the DNN in the first group session parameters is different from the DNN in the second group session parameters; and / or the S-NSSAI in the first group session parameters is different from the S-NSSAI in the second group session parameters.

[0101] In step 406, the SMF network element receives information from the relay UE.

[0102] Here, the information from the relay UE includes a first correspondence between the first RSC and the second group session parameter.

[0103] In step 408, the SMF network element determines whether the first RSC and the second RSC are the same according to the first corresponding relationship and the second corresponding relationship between the first group session parameter and the second RSC.

[0104] In step 410, the SMF network element determines that the remote UE and the relay UE belong to the same group when the first RSC and the second RSC are the same.

[0105] It should be understood that when the first RSC and the second RSC are different, the SMF network element determines that the remote UE and the relay UE do not belong to the same group.

[0106] In step 412, the DDNMF network element receives an address allocation request from the relay UE.

[0107] Here, the address allocation request may carry the IP address of the relay UE and the identifier of the remote UE.

[0108] For example, the relay UE may support a Dynamic Host Configuration Protocol (DHCP) proxy function. After receiving an address allocation request from a remote UE, the relay UE may send an address allocation request to a DDNMF network element by executing the DHCP proxy function to request the DDNMF network element to allocate an IP address to the remote UE.

[0109] In step 414, the DDNMF network element sends the IP address allocated to the remote UE to the relay UE.

[0110] For example, the DDNMF network element may support a DHCP server function to allocate an IP address to a remote UE from a pre-set address pool.

[0111] In some embodiments, the IP address of the remote UE may be different from the IP address of the relay UE.

[0112] In step 416, the relay UE sends the IP address allocated by the DDNMF network element to the remote UE to the remote UE.

[0113] In some embodiments, the remote UE1 or the remote UE2 may provide the corresponding QOS rules to the relay UE through the L2 link modification process. The relay UE may initiate a session modification process to convert the data packets of the remote UE1 or the remote UE2 into corresponding QOS flows, thereby implementing QOS control of the remote UE1 or the remote UE2.

[0114] In step 418, the DDNMF network element sends the session context update information of the relay UE to the SMF network element.

[0115] Here, the session context update information of the relay UE includes the correspondence between the IP address of the relay UE and the IP address of the remote UE.

[0116] In step 420, the SMF network element constructs a session control policy based on the session context update information, treating the first group session and the second group session as group sessions of the same group.

[0117] Here, the session control policy includes a group session forwarding policy.

[0118] In step 422, the SMF network element updates the forwarding table and session control execution rules of the UPF network element according to the session context update information.

[0119] In some embodiments, the UPF network element may forward data packets of the remote UE according to the updated forwarding table so that the remote UE can access the data network.

[0120] Figure 4 The detailed description of the method can be found in the above Figures 1 to 3 The description of the related embodiments shown will not be repeated here.

[0121] In some embodiments, the session control method may include Figure 4 One or more of the steps shown.

[0122] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the network element and system embodiments, since they basically correspond to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0123] Figure 5 It is a structural diagram of an SMF network element according to some embodiments of the present disclosure.

[0124] like Figure 5 As shown, the SMF network element 500 includes a session establishment module 501 and a session control module 502.

[0125] The session establishment module 501 can be configured to establish a first group session for the relay UE in response to a first session establishment request from the relay UE, the first session establishment request carrying a first group session parameter; and to establish a second group session for the relay UE for group communication with the remote UE in response to a second session establishment request from the relay UE, the second session establishment request carrying a second group session parameter, and the second group session parameter is different from the first group session parameter.

[0126] The session control module 502 may be configured to perform session control on the first group session and the second group session in corresponding groups respectively, and to perform session control on the first group session and the second group session as group sessions of the same group when the remote UE and the relay UE belong to the same group.

[0127] In some embodiments, the SMF network element 500 may also include other modules that perform the above-mentioned other operations.

[0128] Figure 6 It is a structural diagram of an SMF network element according to other embodiments of the present disclosure.

[0129] like Figure 6 As shown, the SMF network element 600 includes a memory 601 and a processor 602 coupled to the memory 601, and the processor 602 is configured to execute a method of any of the aforementioned embodiments based on instructions stored in the memory 601.

[0130] The memory 601 may include, for example, a system memory, a fixed non-volatile storage medium, etc. The system memory may store, for example, an operating system, an application program, a boot loader, and other programs.

[0131] The SMF network element 600 may also include an input / output interface 603, a network interface 604, a storage interface 605, etc. These interfaces 603, 604, 605, and the memory 601 and the processor 602 may be connected, for example, via a bus 606. The input / output interface 603 provides a connection interface for input / output devices such as a display, a mouse, a keyboard, and a touch screen. The network interface 604 provides a connection interface for various networked devices. The storage interface 605 provides a connection interface for external storage devices such as an SD card and a USB flash drive.

[0132] Figure 7 It is a structural diagram of a conversation control system according to some embodiments of the present disclosure.

[0133] like Figure 7As shown, the session control system 700 includes an SMF network element 701 of any one of the above embodiments (for example, the SMF network element 701 may be the SMF network element 500 / 600) and a DDNMF network element 702.

[0134] The DDNMF network element 702 may be configured to receive an address allocation request from the relay UE, and send the remote UE's IP address allocated to the remote UE to the relay UE, wherein the address allocation request carries the relay UE's IP address and the remote UE's identifier.

[0135] In some embodiments, the session control system 700 may further include a relay UE 703 of any of the above embodiments. The relay UE 703 may be configured to send a first session establishment request and a second session establishment request to the SMF network element 701 , and send an address allocation request to the DDNMF network element 702 .

[0136] The embodiments of the present disclosure further provide a computer-readable storage medium, comprising computer program instructions, which implement the method of any one of the above embodiments when executed by a processor.

[0137] The embodiments of the present disclosure further provide a computer program product, including a computer program, wherein when the computer program is executed by a processor, the method of any one of the above embodiments is implemented.

[0138] So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.

[0139] Those skilled in the art will appreciate that the embodiments of the present disclosure may be provided as methods, systems, or computer program products. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present disclosure may take the form of a computer program product implemented on one or more computer-usable non-transient storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0140] The present disclosure is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present disclosure. It should be understood that the functions specified in one or more processes in the flowchart and / or one or more blocks in the block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the functions specified in the flowchart. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0141] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0142] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0143] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A session control method, comprising: The session management function SMF network element establishes a first group session for the relay user equipment UE in response to a first session establishment request from the relay user equipment UE, where the first session establishment request carries a first group session parameter; The SMF network element establishes, in response to a second session establishment request from the relay UE, a second group session for the relay UE for group communication with the remote UE, wherein the second session establishment request carries a second group session parameter, and the second group session parameter is different from the first group session parameter; The SMF network element performs session control on the first group session and the second group session in corresponding groups respectively, and when the remote UE and the relay UE belong to the same group, the first group session and the second group session are session controlled as group sessions of the same group.

2. The method according to claim 1, further comprising: The SMF network element determines the group to which the remote UE belongs and the group to which the relay UE belongs according to the first group session parameter and the second group session parameter.

3. The method according to claim 2, further comprising: The SMF network element receives information from the relay UE, where the information includes a first correspondence between a first relay service code RSC and the second group session parameter; The SMF network element determines whether the first RSC and the second RSC are the same according to the first corresponding relationship and the second corresponding relationship between the first group session parameter and the second RSC; When the first RSC and the second RSC are the same, the SMF network element determines that the remote UE and the relay UE belong to the same group.

4. The method according to claim 1, wherein: The data network name DNN in the first group session parameter is different from the DNN in the second group session parameter; and / or The single network slice selection assistance information S-NSSAI in the first group session parameters is different from the S-NSSAI in the second group session parameters.

5. The method according to claim 1, wherein: The remote UE accesses the core network via the relay UE in the L3 network, and the access to the core network does not pass through a non-3GPP interworking function N3IWF network element.

6. The method according to claim 1, further comprising: The SMF network element receives the IP address of the remote UE sent by the relay UE, and the IP address of the remote UE is different from the IP address of the relay UE.

7. The method according to claim 6, further comprising: The direct discovery name management function DDNMF network element receives an address allocation request from the relay UE, where the address allocation request carries the IP address of the relay UE and the identifier of the remote UE; The IP address of the remote UE allocated to the remote UE is sent to the relay UE.

8. The method according to claim 7, wherein: The IP address of the remote UE and the IP address of the relay UE are located in the same network segment.

9. The method according to claim 7, wherein: The IP address of the remote UE is an IPv4 address.

10. The method according to claim 7, further comprising: The SMF network element receives session context update information of the relay UE from the DDNMF network element, where the session context update information includes a correspondence between the IP address of the relay UE and the IP address of the remote UE; The SMF network element performs session control on the first group session and the second group session as group sessions of the same group, including: The SMF network element constructs a session control policy based on the session context update information, taking the first group session and the second group session as group sessions of the same group, where the session control policy includes a group session forwarding policy.

11. The method according to any one of claims 1 to 10, wherein: The first group session and the second group session are both virtual network VN group sessions.

12. An SMF network element, comprising: a session establishing module, configured to establish a first group session for the relay UE in response to a first session establishing request from the relay UE, wherein the first session establishing request carries a first group session parameter; and establishing, in response to a second session establishment request from the relay UE, a second group session for the remote UE to perform group communication for the relay UE, wherein the second session establishment request carries a second group session parameter, and the second group session parameter is different from the first group session parameter; The session control module is configured to perform session control on the first group session and the second group session in corresponding groups respectively, and when the remote UE and the relay UE belong to the same group, perform session control on the first group session and the second group session as group sessions of the same group.

13. An SMF network element, comprising: Memory; as well as A processor coupled to the memory, configured to execute the method according to any one of claims 1 to 6 based on instructions stored in the memory.

14. A conversation control system, comprising: The SMF network element of claim 12 or 13, and The DDNMF network element is configured to receive an address allocation request from the relay UE, where the address allocation request carries the IP address of the relay UE and the identifier of the remote UE; and send the IP address of the remote UE allocated to the remote UE to the relay UE.

15. The system of claim 14, further comprising: The relay UE is configured to send the first session establishment request and the second session establishment request to the SMF network element, and send the address allocation request to the DDNMF network element.

16. A computer-readable storage medium comprising computer program instructions, wherein: When the computer program instructions are executed by a processor, the method according to any one of claims 1 to 11 is implemented.

17. A computer program product comprising a computer program, wherein: When the computer program is executed by a processor, the method according to any one of claims 1 to 11 is implemented.

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